Container Service Procedures.pdf

7/27/2019 Container Service Procedures.pdf

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CONTAINER 69NT

SERVICE PROCEDURES


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TABLE OF CONTENTS

1. Troubleshooting tips.

3. Diode testing procedure.

4. Relay testing procedure.6. Refrigeration component identification.

7. Refrigeration system diagram.

8. Analog control electrical component identification.

10. Microlink control electrical component identification.

12. Microlink 2 & 2i control electrical component identification.

14. Service valves

15. Manifold gauge set installation and removal procedure.

18. Low side pumpdown procedure.

19. O6DR compressor operation test procedure.

20. Compressor oil level test procedure.

22. Superheat test procedure.24. Analog controller 30 second test procedure.

26. Modulation and quench valve test procedure. (Analog control)

27. Modulation and quench valve test procedure. (Microlink, Microlink 2 & 2i)

28. CSS resistance test procedure. (Analog control)

29. Temperature sensor resistance test procedure. (Analog control)

30. Temperature sensor resistance test procedure. (Microlink, Microlink 2 & 2i)

31. Temperature control simulator module. (Analog control)

33. Motor and heater resistance test procedure.

35. Motor and heater current test procedure.

36. Refrigerant charge level test procedure.

37. Refrigerant charging procedure.38. Refrigerant color codes

39. Refrigerant recovery procedure.

41. Evacuation procedure.

42. Boiling temperature of water

46. Dual voltage compressor internal resistance readings.


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TROUBLESHOOTING TIPS

1. Always connect a voltmeter in parallel. When troubleshooting grounded low voltage control

circuits, (24VAC, 12VDC, etc) use a clip-on connection from the meter negative (black) lead to

unit ground. This will leave one hand free to operate switches, etc. Always test the meter setup

on a known voltage before troubleshooting. When troubleshooting high voltage (230VAC,

460VAC, etc) check voltages from phase to phase and not to ground. Check that the meter is on

the proper scale. If unsure, select the highest scale first and then select progressively lower

scales until the value displayed is approximately in the middle of the scale.

2. Ohmmeters are always connected in parallel on de-energized circuits. At least one side (lead) of

the component being tested must be disconnected from the circuit to isolate that component

from the rest of the circuit. Resistance readings must not be taken with power applied to the

component. Always test the ohmmeter by touching the meter leads together to test the meter for

proper operation. It should read 0 ohms (or very low). Check that the meter is on the proper

scale.

3. Always connect DC ammeters in series with the circuit being tested. You must "break" the

circuit and connect the meter in series. The meter becomes part of the circuit under test.

4. To locate a unit problem, operate the unit in all modes of operation: full cool, full cool with

bypass, modulated cooling, air circulation, heat, and defrost. Check the operation of the

modulation valve and the quench valve. Note the suction and discharge pressures in all modes

of operation.

5. When troubleshooting electrical faults, it is necessary to know how the unit operates and what is

supposed to happen. It is suggested that the meter negative (black) lead be first connected to

ground or common. Check the operation of the meter by touching the red meter lead on aknown source of voltage. Starting at he left of the schematic and at supply voltage, work your

way across the schematic towards the circuit load by testing consecutive connection points until

the voltage is not found. The problem or fault in the circuit will be between the points where

voltage was found and where voltage was not found.

Example: If on an analog unit the heat contactor (HR) will not close, first check for control

voltage (24VAC) at mother board terminal T9 then continue to the right towards the load (HR

contactor coil). Test for 24VAC at T8, T10, T11, and C1 on the HR contactor. If voltage is not

found at a test point, the problem lies between that point and the last point tested. Be sure to

check the obvious visual indications such as the LED's on the motherboard.


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CLAMP-ON AMMETER

The clamp-on ammeter is a small, versatile test instrument used by technicians for measuring AC

current or amps.

The clamp-on ammeter works like a transformer. The wire acts like the primary of the transformer

and the jaws of the ammeter as the secondary. Current through the wire creates lines of force that

induce a current in the jaws. The induced current passes through the meter movement, providing an

indication of how much current is passing through the wire.

When taking a current reading, always start on the highest possible scale and work towards the lower

scale to prevent damage to the meter. Do not cycle a motor off and back on with the meter clamped

onto the motor lead, unless you first set the meter to the highest scale. This will prevent damage

from current surges.

Never clamp the meter around two different wires (phases) at the same time. If currents are flowing

in opposite directions, the meter will read the difference between the two. If current is flowing in the

same direction, the meter will read the sum of the two.

An example of where an ammeter would be used on a refrigeration unit would be to check the amp

draw on the compressor when the unit is operating in the cool mode.


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DIODE TESTING PROCEDURE

The diodes used in Carrier Transicold equipment are solid state devices that conduct electrical current in one

direction only. They are used for circuit isolation and arc suppression.

CIRCUIT ISOLATION

When used for circuit isolation, diodes are connected in order to prevent one energized circuit from energizing

another.

An example of this is diode D1, found in the glow plug circuit for the Carrier Transicold diesel powered

generator set model #69GL15-114, drawing #69GL15-1094-RA. Diode D1 is used to prevent the low oi

pressure switch from energizing the glow plugs when the engine is running.

ARC SUPPRESSION

When diodes are used for arc suppression, they are usually connected across inductive loads. An inductive load

is any load made up of a coil of wire.

Examples are: relay coils, solenoid valve coils, speed and run solenoids and unloader coils. When any inductive

load is de-energized, it instantaneously generates a very high voltage spike. This high voltage spike can destroy

the relay contacts that control the load. A relay that has pitted, burnt or welded together contacts may be the

result of a defective arc suppression diode.

TESTING A DIODE

Before a diode can be tested using an ohmmeter, the diode must be isolated from the circuit to which it is

connected.

Using an analog meter

To use an analog volt-ohm-milliammeter (vom) to test diodes, select the ohms R x 1 scale. A good diode

should read very low resistance in one direction and very high in the other direction.

Using a digital meter

Because a digital meter has limited power output in the ohm's scale, it cannot be used to test a diode in the same

way as an analog meter. A good diode tested on the ohms scale on a digital meter would read infinite ohms in

both directions, incorrectly indicating a defective diode. On digital vom's you must use the diode test scale

When using this scale to test a diode, the meter will read the voltage at which the diode begins to conduct in theforward direction. A normal reading will usually be .4 to .7 Volts. Very high or very low readings indicate a

defective diode. In the reverse direction, the diode will not conduct and the meter will indicate "OL" or an open

circuit. Any other indication signifies a defective diode.


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RELAY TESTING PROCEDURE

FOR RELAY (PART #10-00220)

1. Turn the unit off and remove the suspect relay from its socket on the motherboard. Refer to the

diagram below.

2. Check the coil for continuity with an ohmmeter by placing the ohmmeter leads on the coil

terminals. The coil terminals will be labeled "C". A good coil will have a resistance of

approximately 115 ohms. A resistance value of 0 ohms or infinite ohms indicates a defective

coil.

3. Continuity (0 or nearly 0 ohms) should be found between the common (C) and the normally

closed (NC) terminals. The common terminals are numbers 1, 4, and 7. The normally closed

terminals are numbers 2, 5, and 8. Therefore you should measure 0 or nearly 0 ohms between

terminals 1 & 2, 4 & 5, and 7 & 8.

4. No continuity (infinite resistance) should be found between the common (C) and normally open

(NO) terminals. The normally open terminals are 3, 6, and 9. Therefore you should measure

infinite (very high) resistance between terminals 1 & 3, 4 & 6, and 7 & 9.

5. To test the normally open (NO) contacts it is necessary to energize the relay coil. Connect a

12VDC-power supply to the coil terminals. You should be able to see the contacts change

position. Continuity should now be found between the common and normally open terminals

and there should be no continuity between the common and normally closed terminals.

9- NO 6- NO 3- NO

5- NC8- NC 2- NC

C - 1C - 7

C - 4

Coil Coil

Legend

NC - Normally Closed

NO - Normally Open

C - Common


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CONTAINERREFRIGERATION COMPONENT IDENTIFICATION

Referring to the following unit refrigeration diagram, locate the designated component on the

unit and write the name and location of that component below.

Reference number Component name & location

1. __________________________________________________

2. __________________________________________________

3. __________________________________________________

4. __________________________________________________

5. __________________________________________________

6. __________________________________________________

7. __________________________________________________

8. __________________________________________________

9. __________________________________________________

10. __________________________________________________

11. __________________________________________________

12. __________________________________________________

13. __________________________________________________

14. __________________________________________________

15. __________________________________________________

16. __________________________________________________

17. __________________________________________________

18. __________________________________________________


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R134a

5

17

16

15

9

10

14

13 11

121

182

34

8

76

R125

4

17

15

10

3 8

12

14

1

9

2

1611

13

6

7


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ANALOG UNIT ELECTRICAL COMPONENT IDENTIFICATION

Symbol Description & location

C __________________________________________________

CB1 __________________________________________________

CB2 __________________________________________________

CF __________________________________________________

CL __________________________________________________

CLT __________________________________________________

CM __________________________________________________

CP __________________________________________________

CSS __________________________________________________

DD __________________________________________________

DHBL __________________________________________________

DIS __________________________________________________

DL __________________________________________________

DPH __________________________________________________

DR __________________________________________________

DTT __________________________________________________

EF __________________________________________________

EM __________________________________________________

ES __________________________________________________

F __________________________________________________

HL __________________________________________________

HPS __________________________________________________

HR __________________________________________________

HTT __________________________________________________


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IRL __________________________________________________

IRS __________________________________________________

MDS __________________________________________________

QV __________________________________________________

RM __________________________________________________

RTS __________________________________________________

SDS __________________________________________________

SMV __________________________________________________

SSS __________________________________________________

SST __________________________________________________

ST __________________________________________________STS __________________________________________________

TB __________________________________________________

TC __________________________________________________

TDS __________________________________________________

TH __________________________________________________

TU __________________________________________________

TQ __________________________________________________

TR __________________________________________________

TSS __________________________________________________

VS __________________________________________________

UNIT MODEL NUMBER ___________________________________

UNIT SERIAL NUMBER ___________________________________

REFRIGERANT CHARGE ___________________________________


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MICROLINK UNIT ELECTRICAL COMPONENT IDENTIFICATION


AMBS __________________________________________________

C __________________________________________________

CB1 __________________________________________________

CB2 __________________________________________________

CF __________________________________________________

CM __________________________________________________

CP __________________________________________________

CPDS __________________________________________________

CPSS __________________________________________________

CSAS __________________________________________________

CT __________________________________________________

DHBL __________________________________________________

DPH __________________________________________________

DTT __________________________________________________

EF __________________________________________________

EM __________________________________________________

ES __________________________________________________

HCS __________________________________________________

HPS __________________________________________________

HR __________________________________________________

HTT __________________________________________________

IC __________________________________________________

MDS __________________________________________________

PP __________________________________________________

PR __________________________________________________


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PT __________________________________________________

QV __________________________________________________

R __________________________________________________

RM __________________________________________________

RRS __________________________________________________

RTS __________________________________________________

SMV __________________________________________________

SRS __________________________________________________

SSV __________________________________________________

ST __________________________________________________

STS __________________________________________________TB __________________________________________________

TC __________________________________________________

TE __________________________________________________

TFC __________________________________________________

TI __________________________________________________

TH __________________________________________________

TN __________________________________________________

TQ __________________________________________________

TS __________________________________________________

TV __________________________________________________

WP __________________________________________________





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MICROLINK 2 AND MICROLINK 2i UNIT ELECTRICAL COMPONENT IDENTIFICATION


AMBS __________________________________________________

C __________________________________________________

CB1 __________________________________________________

CB2 __________________________________________________

CH __________________________________________________

CI __________________________________________________

CL(C-L) __________________________________________________

CM __________________________________________________

CP __________________________________________________

CPDS __________________________________________________

CPSS __________________________________________________

CPT __________________________________________________

DHBL __________________________________________________

DPH __________________________________________________

DR(TF) __________________________________________________

DTS __________________________________________________

DVM __________________________________________________

EF __________________________________________________

EM __________________________________________________

ES __________________________________________________

HPS __________________________________________________

HR __________________________________________________

HS __________________________________________________

HTT __________________________________________________

HVM(CS) __________________________________________________


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IC __________________________________________________

MDS __________________________________________________

PR __________________________________________________

RM __________________________________________________

RRS __________________________________________________

RTS __________________________________________________

SMV __________________________________________________

SRS __________________________________________________

SSV __________________________________________________

ST __________________________________________________

STS __________________________________________________

TC __________________________________________________

TE __________________________________________________

TH __________________________________________________

TI __________________________________________________

TN __________________________________________________

TP __________________________________________________

TR __________________________________________________

TS __________________________________________________

VS __________________________________________________

WP __________________________________________________





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Service Valves


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MANIFOLD GAUGE SET INSTALLATION AND REMOVAL PROCEDURE

Before using a manifold gauge set it is important that it be purged. This insures that air and other contaminates

will not be introduced into the refrigeration system. Manifold gauge sets using hoses without self-sealing ends

must be purged every time that they are used. Manifold gauge set hoses with self sealing ends must be purged

or evacuated and charged with refrigerant when: 1) the hoses have been disconnected from the manifold or 2)

they will be used on a refrigeration system with different refrigerant than previously serviced units.

While in use, a manifold gauge set high side hose will fill with condensed liquid refrigerant. When the high

side hose is removed from the compressor discharge service valve, liquid refrigerant will be released. It is

because of this liquid release that the proper procedure for removing the manifold gauge set be followed.

SAFETY GLASSES AND GLOVES SHOULD ALWAYS BE WORN WHEN INSTALLING OR

REMOVING A MANIFOLD GAUGE SET. PLEASE FOLLOW LOCAL ENVIRONMENTAL LAWS

WHEN REFERRING TO THESE INSTRUCTIONS.

TO INSTALL THE CFC MANIFOLD GAUGE SET

Installing CFC manifold gauge sets WITHOUT self-sealing hoses.

1. Remove the valve stem caps from the compressor suction and discharge service valves.

BACKSEATboth valves. Remove the caps from the service ports.

2. Connect the high side hose to the compressor discharge service valve and tighten the hose

connection.

3. Connect the low side hose loosely to the compressor suction service valve port. The center

(utility) hose should be connected loosely to the center "dummy fitting" on the manifold gauge

set.

4. To purge the hoses and manifold, backseat the manifold valves, midseat (slightly open) the

compressor discharge service valve. Refrigerant from the discharge service valve will force air

and contaminants from the manifold and hoses and out through the loosely connected center

hose at he "dummy fitting" and at the suction service valve. After hearing gas escape for a few

seconds tighten the center hose connection at the "dummy fitting" and then at the suction service

valve. Frontseat the manifold gauge set valves to isolate the high and low sides from each other.

Midseat the suction service valve.


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Installing CFC manifold gauge sets WITH self-sealing hoses.



If a manifold gauge set is new or was exposed to the atmosphere. Due to repair, it will need to be

evacuated to remove contaminants and air as follows:

a. Midseat both hand valves.b. Connect the utility hose (yellow) to a vacuum pump.c. Evacuate to 10 inches of vacuum.

d. Charge with proper refrigerant to a slightly positive pressure of 1.0 psig (0.1 kg/cm2)e. The gauge set is now ready for use.

2. Connect the high side hose to the discharge service valve port and tighten. Do not connect the

center or the low side hose. Backseat the manifold gauge valves, midseat (slightly open) the

compressor discharge service valve.

If the manifold gauge set has been used on refrigeration equipment with the same

refrigerant and the hoses have not been removed (the gauge set displays internal pressure

on the gauges), skip step 3.

3. To purge air and contaminants from the manifold and hoses, use a 1/4 flare fitting or other

instrument to open, for a few seconds, the self sealing valve in the end of the center hose and

then in the low side hose. This will purge the air from the hoses and manifold and leave the

manifold and hoses full of refrigerant vapor.

POINT THE HOSES IN A SAFE DIRECTION WHEN PURGING.PLEASE FOLLOW LOCAL

ENVIRONMENTAL LAWS WHEN REFERRING TO THESE INSTRUCTIONS.

4. Connect the low side hose to the compressor suction service valve port. Connect the center

(utility) hose to the center "dummy fitting" on the manifold gauge set. Midseat the suction

service valve. Frontseat the manifold gauge set valves to isolate the high and low sides from

each other.


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Installing HFC (R-134a) manifold gauge sets.



If a manifold gauge set is new or was exposed to the atmosphere. Due to repair, it will need to be

evacuated to remove contaminants and air as follows:

a. Midseat both hand valves.b. Connect the utility hose (yellow) to a vacuum pump.

c. Evacuate to 10 inches of vacuum.d. Charge with R-134a to a slightly positive pressure of 1.0 psig (0.1 kg/cm2)e. The gauge set is now ready for use.

2. Connect the high side field service coupling (backseated) to the discharge service valve port (or

the manual liquid line valve port, whichever is applicable).

3. Turn the high side field service coupling (red knob) clockwise, which will open the high side ofthe system to the gauge set.

4. Connect the low side field service coupling to the suction service valve port.

5. Turn the low side field service coupling (blue knob) clockwise, which will open the low side ofthe system to the gauge set.

6. To read system pressures: slightly midseat the discharge and suction service valves and

Frontseat both manifold gauge set hand valves.

TO REMOVE ALL MANIFOLD GAUGE SETS

1. With the compressor running, backseat the compressor discharge service valve.

2. Midseat both valves on the manifold gauge set and allow the pressure in the manifold gauge set

to be drawn down to suction pressure. This procedure for removing the manifold gauge set

allows the liquid that condensed in the high side hose to be returned to the system. This will

leave the manifold gauge set internal pressure equal to suction pressure.

3. Backseat the compressor suction service valve. Backseat both field service couplings, and

remove the couplings from the service ports.

4. Install both service valve stem caps and service port caps (finger-tight only).


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LOW SIDE PUMPDOWN PROCEDURE

1. Install the manifold gauge set. Start the unit and allow it to run for 15 to 20 minutes.

2. Front seat the manual liquid line valve (king valve).

3. Operate the unit in cool mode until suction pressure reaches a positive pressure of 1.0 psig (0.1

kg/cm). Turn unit off.

WARNING: DO NOT ALLOW THE SYSTEM TO OPERATE IN A VACUUM AS

COMPRESSOR DAMAGE MAY RESULT.PLEASE FOLLOW LOCAL ENVIRONMENTAL

LAWS WHEN REFERRING TO THESE INSTRUCTIONS.

4. Watch suction pressure gauge. Typically the pressure will rise a small amount. Ideally, the

pressure should stabilize at 1 to 2 psig.

5. If the pressure climbs too high it may be necessary to re-start the unit and allow it to run for a

few more seconds. If the suction pressure stabilizes too low (vacuum), momentarily midseat

both valves on the manifold gauge set to allow refrigerant from the high side to enter the low

side through the manifold gauge set.

6. When the pressure is stabilized at 1 to 2 psig, Frontseat the suction service valve. The entire

refrigerant charge is now trapped in the compressor, condenser and receiver sections of the

system. All system components with the exception of the discharge service valve, high side

fusible plug, condenser, suction/liquid heat exchanger, receiver/water cooled condenser and the

king valve can be changed or serviced.

7. After completing repairs, be sure to perform a refrigerant leak check and evacuate and dehydrate

the low side of the system through the service port on the liquid line valve (king valve).

8. To return the unit to service, back seat the liquid line valve and the suction service valve (SSV).


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06DR COMPRESSOR OPERATION TEST PROCEDURE

COMPRESSOR HIGH PRESSURE TEST

With the unit operating in cool mode, partially block the condenser airflow. Discharge pressure should rise to at

least 250 psig for systems using R-12 and R-134a. Don't let discharge pressure rise enough to cause the high

pressure safety to open and shut the unit off. Failure of the compressor to reach high discharge pressures

may indicate worn or broken piston rings, worn or broken valves or defective head gaskets. Inability to

operate at high discharge pressures will reduce refrigerating capacity when ambient temperatures are high.

REASONS FOR FAILURE- Blown cylinder head gasket.

Broken or worn valves.

Flooded starts.

Slugging.

Flooding.

Overcharge/undercharge of oil.Defective TXV.

Contaminates in the system.


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CHECKING COMPRESSOR OIL LEVEL

A common error in servicing and maintaining Carrier Transicold container refrigeration equipment is

over charging the refrigeration system with oil. A general statement referring to oil level is; if there is

oil visible in the sight glass, don't add any.

1. Operate the unit in the cooling mode for at least 20 minutes.

2. Check the front oil sight glass on the compressor to ensure that no foaming of the oil is present

after 20 minutes of operation. If the oil is foaming excessively after 20 minutes of operation,

check the refrigerant system for flood-back of liquid refrigerant. Correct this situation before

performing step 3.

3. Turn the unit off to check the oil level. The correct oil level range should be as follows:

28 CFM compressor - 0 to 1/2 of the sightglass

37 CFM compressor - 0 to 3/8 of the sightglass41 CFM compressor - 0 to 1/8 of the sightglass

Compressor size is identified by the 6th and 7th digit of the model number. Example: model number

06DR2418CC19AC is a 41 CFM compressor.

If the oil level is too high, remove enough to lower the oil level to the proper level. If the oil level is

too low, run the system in heat for 15 to 20 minutes and then in cool for 15 to 20 minutes and recheck.

If the oil level is still low then add oil. This insures that a large amount of oil is not out in the system,

giving an erroneous low reading.

TO REMOVE COMPRESSOR OIL

Install a manifold gauge set. Frontseat (close) the suction service valve. Run the compressor until the

suction pressure falls into a slight vacuum. Turn off the unit and observe the suction pressure. It is

necessary for the pressure to stop at a slight positive pressure of 1 to 2 psig (0.1 to 1.2 kg/cm). If

pressure rises too high, run the compressor for a few more seconds. If the pressure remains too low,

momentarily open both hand valves on the manifold gauge set. This allows some refrigerant from the

high side to pass through the manifold and raise the low side pressure.

When the pressure is correct and stabilized, remove power from the unit and secure the power plug toavoid accidentally starting the compressor. Front seat the suction and discharge service valves to isolate

the compressor from the system. Carefully relieve the remaining compressor internal pressure by

removing the manifold gauge set hose from the suction service valve. PLEASE FOLLOW LOCAL

ENVIRONMENTAL LAWS WHEN REFERRING TO THESE INSTRUCTIONS.The oil drain

plug can now be safely removed and excess oil drained from the compressor crankcase.


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TO ADD COMPRESSOR OIL

Use only recommended oils. For R-12 units use mineral oil (Texaco wf32). For R-134a units use POE oi

(Castrol Icematic SW20).

With the compressor running and the suction service valve front seated, oil can be drawn into the suction

service valve through the manifold gauge set. If the center hose (use a hose withouta self-sealing valve) is

submerged in a container of compressor oil and the low side manifold valve opened, oil will be drawn through

the manifold and into the compressor.

Be sure to purge the center hose after it is submerged in the oil container.

PLEASE FOLLOW LOCAL ENVIRONMENTAL LAWS WHEN REFERRING TO THESE

INSTRUCTIONS.

To purge the center hose:

1. Attach a manifold gauge set to the compressor and purge if necessary. Midseat the discharge

service valve and Frontseat the suction service valve.

2. Drop the center manifold hose into the compressor oil container. Be sure that the end of the hose

is submerged and remains submerged throughout this procedure.

3. Slightly midseat the high side manifold valve. Refrigerant from the discharge service valve will

force air from the center hose and will bubble into the oil. After a few seconds, Frontseat

(close) the high side manifold valve.

There are oil pumps available for compressor oil containers that will pump oil directly into the suction servicevalve. The compressor must be running with the suction service valve midseated. The pump will overcome

suction pressure. Add oil carefully as not to over fill the crankcase.


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SUPERHEAT TEST PROCEDURE

1. Check the calibration of the manifold test set gauges, especially the suction gauge. Adjust if

necessary.

2. Install an accurate gauge to the suction service port.

3. Firmly attach a temperature-sensing device to the evaporator coil outlet line at or near the TXVbulb location and insulate the area.

4. Start the unit and set to operate in cool mode for a minimum of 20 minutes. The system must

stabilize with the compressor operating on all 6 cylinders and the High Side pressure at the

following minimum levels - 150 psig for R-134a and 200 psig for R-22.

5. Note the suction gauge reading and the temperature at the TXV sensing bulb (the refrigerantvapor temperature). Record both readings.

6. Repeat step 6 at least five times at two to three minute intervalsand record the information.

7. After recording the five readings, calculate the superheat for each set of readings.

8. Using a pressure - temperature chart determine the saturation temperature at the suction pressure

recorded.

9. To determine superheat, subtract the saturation temperature determined above, from thetemperature measured at the TXV bulb.

10. Average the five superheat figures calculated above and compare to the specification for theunit.

REFER TO OPERATION AND SERVICE MANUAL FOR CORRECT SUPERHEAT.

SEE SAMPLE SUPERHEAT CHECKSHEET ON FOLLOWING PAGE.


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THE ANALOG CONTROLLER 30 SECOND TEST

TO TEST THE FROZEN PROGRAM:

1. Install manifold gauge set. Rotate the temperature set station (CSS) to its full counter-clockwise

position. Start the unit and allow the system to stabilize.

2. Using one hand, depress and hold the time delay switch (TDS) while holding the temperature

simulator switch (TSS) in the -17.8 C (0 F) position. Using the other hand, slowly rotate the

CSS clockwise. The following events should occur at approximately the CSS setpoints

indicated:

Start (TC) on

-19.8 C (-3.6 F) (IRS) on, In-range light on

-17.5 C (0.5 F) (TC) off, Compressor and condenser off

-15.8 C (3.6 F) (IRS) off, In-range light off

-10 C (14 F) (TH) on, Heaters on, (TU) on

3. Reversing the procedure, rotate the CSS counter-clockwise and the following should occur:

Start (TH) on, Heaters on

-10 C (14 F) (TH) off, Heaters off, (TU) off)

-15.8 C (3.6 F) (IRS) on, In-range light on

-18 C (0.4 F) (TC) on, Compressor and condenser on

-19.8 C (-3.6 F) (IRS) off, In-range off

TO TEST THE CHILL OR PERISHABLE PROGRAM:

1. Install manifold gauge set. Rotate the CSS to its full counter-clockwise position. Start the unitand allow the system to stabilize.

2. Using one hand, depress and hold the TDS while holding the TSS in the 0 C (32 F) position.

Slowly rotate the CSS clockwise. The following events should occur at approximately the CSS

setpoints indicated:

Start (TC) on, Compressor and condenser on

-10 C (14 F) (TU) on, Utility relay on

Approx. -5 C (23 F) (TQ) on, Modulation occurs

-2 C (28 F) (IRS) on, In-range light on+0.25 C (32.5 F) (TC) off, Compressor and condenser off

+1 C (34 F) (TH) on, Heaters on

+2 C (36 F) (IRS) off, In-range light off


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3. Reversing the procedure, rotate the CSS counter-clockwise and the following should occur:

Start (TH) on, Heaters on

+2 C (36 F) (IRS) on, In-range light on

+0.5 C (33 F) (TH) off, Heaters off

-0.25 C (31.5 F) (TC) on, Compressor and condenser on

-2 C (28 F) (IRS) off, In-range off

Approx. -5 C (23 F) (TQ) off, Modulation stops

-10 C (14 F) (TU) off, Utility relay off

The quench relay (TQ) will be energized at 50% or more modulation.


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ANALOG CONTROL SUCTION MODULATION and QUENCH VALVE TEST PROCEDURE

FOR ANALOG CONTROLLED UNITS

1. Install the manifold gauge set. Turn the unit on, set the temperature set station (CSS) to -18 C

(0 F) and allow system pressures to stabilize.

2. Using one hand, hold the time delay switch (TDS) in and the temperature simulator switch

(TSS) in the 0 C (32 F) position.

3. Starting with CSS in the full counter clockwise position, with your other hand, slowly rotate the

CSS clockwise. If the modulation circuit is functioning properly you will notice a change in the

sound of the compressor and a significant drop in suction pressure as the modulation valve

begins to close as CSS approaches 0 C (32 F). As the CSS approaches the 0 C (32 F) position,

the suction pressure should be approximately 10-20 inches of mercury vacuum. At this time if aclamp on ammeter is monitoring compressor current, it should drop to a reading below 10 amp.

4. To check the temperature controller's electrical signal to the modulation valve, connect a DC

voltmeter between motherboard terminals T12 (DC common) and T14. Repeat the procedure

above. When the reading is 0.2 VDC or less the modulation valve is fully open. As the voltage

increases, the modulation valve is closing. This may be confirmed by watching the suction

pressure gauge fall as the voltage to the modulation valve increases. A reading of 1.2 to 1.4

VDC indicates a fully closed modulation valve. This voltage reading is equal to modulation

valve current.

5. To check the operation of the quench valve, repeat the procedures of steps 2 and 3 above, while

touching the quench line on the suction line side of the quench valve. When the temperature

controller's electrical signal to the modulation valve exceeds 0.62 amps the TQ relay will be

energized (TQ LED on). This energizes the quench valve, causing it to open. This may be

confirmed by noting a significant drop in the temperature of the quench line and a slight increase

in suction pressure.

If the SMV coil is defective and open, TQ will not be energized and the quench valve will

fail to function.


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SUCTION MODULATION VALVE and QUENCH VALVE TEST PROCEDURE

FOR MICROLINK, MICROLINK 2 AND MICROLINK 2I CONTROLLED UNITS

1. Install the manifold gauge set. Turn the unit on. Using the keypad, set the set point to a

temperature significantly below the container temperature. This will cause the unit to run in

cool mode.

2. At start up the microprocessor may close the suction modulation valve (SMV). The modulation

valve will be allowed to open at a rate of 1% per second until fully open. This can be viewed by

displaying code 01. Code 01 will indicate the percent of opening of the SMV as directed by the

microprocessor. It does not mean that the SMV operated correctly as the circuit is not

monitored directly.

3. The correct operation of the SMV can be checked by two methods:

START THE UNIT IN COOL MODE WITH THE SETPOINT 5 C TO 10 C BELOW

THE CONTAINER TEMPERATURE. AFTER THE SYSTEM HAS STABILIZED,

CHANGE THE SETPOINT TO EQUAL THE CONTAINER TEMPERATURE.

a. Watch the suction gauge pressure drop into a vacuum when the SMV closesafter the setpoint is set to a temperature equal to the container temperature.

b. Using a clamp on ammeter, monitor compressor current. After the setpoint is setto a temperature equal to the container temperature the compressor current will

usually fall below 10 amps. This drop in compressor current indicates that theSMV closed.

4. To check the operation of the quench valve (electric solenoid operated quench valve with a

Microlink control), monitor code 02. The operation of the quench valve is indicated as "open"

or "closed". When the electrical current through the suction modulation valve solenoid coil

exceeds 0.62 amps (when 47% open or less is indicated by code 01) the quench valve will be

energized. This may be confirmed by noting a significant drop in the temperature of the quench

line and a slight increase in suction pressure. Power to the quench valve can be confirmed by

reading the voltage at TB9. There should be 24 VAC at TB9 anytime code 02 indicates "open".

If the SMV coil is defective and open, the quench valve will fail to function and theMicrolink will fail the pretrip tests P6-2 (QV test) and P6-3 (SMV closed).


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TEMPERATURE SET STATION (CSS) RESISTANCE TEST PROCEDURE


1. BEFORE PROCEEDING, TURN UNIT OFF, OPEN CIRCUIT BREAKER(S),

DISCONNECT AND SECURE POWER CORD.

2. Isolate the temperature set station by disconnecting it from the motherboard at plug P8.

PLEASE NOTE:When testing at the plug, always insert the meter probes from the back (wire

side) of the plug. This prevents bending of the plug terminals, which could result in a poor

connection when the plug is replaced on the motherboard.

3. Measure the resistance between CSS 1 (the brown wire) and CSS 3 (the orange wire).

Regardless of the selector setting the resistance should be 1980 to 1988 ohms.

4. Set the selector at the -25 C (-15 F) position. The resistance between CSS 1 and CSS 2 (brownwire to red wire) should be 324 to 334 ohms. The resistance between CSS 2 and CSS 3 (red

wire to orange wire) should be 1648 to 1656 ohms.

5. Set the selector at the 0 C (32 F) position. The resistance between CSS 1 and CSS 2 (brown

wire to red wire) should be 980 to 988 ohms. The resistance between CSS 2 and CSS 3 (red


6. Set the selector at the 25 C (77 F) position. The resistance between CSS 1 and CSS 2 (brown

wire to red wire) should be 1633 to 1641 ohms. The resistance between CSS 2 and CSS 3 (red


IF THE MEASURED RESISTANCES ARE FOUND TO BE SIGNIFICANTLY DIFFERENT

THAN THE LISTED VALUES, REPLACE THE TEMPERATURE SET STATION.


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TEMPERATURE SENSOR RESISTANCE TEST PROCEDURE


1. BEFORE PROCEEDING, TURN UNIT OFF, OPEN CIRCUIT BREAKER(S),


2. Isolate the temperature sensor to be tested by disconnecting it from the motherboard at the

appropriate plug. Plug P10 for the supply temperature sensor (STS) or P11 for the return

temperature sensor (RTS).

3. Determine the temperature in the area where the sensor is located. An alternate method is to

place the sensor in a 0 C (32 F) ice bath or measure the temperature at the probe location with a

known standard.

4. Measure the resistance of the sensor by placing the meter leads on the back (wire side) of the

plug. For the STS, use pins 1 & 2 on P10, for the RTS use pins 3 & 4 on P11.

5. Compare the measured resistance value to the SENSOR RESISTANCE chart found on page 28

of the 69NT20/40 SERVICE TRAINING MANUAL.

IF THE MEASURED RESISTANCE IS FOUND TO BE SIGNIFICANTLY DIFFERENT

THAN THE LISTED VALUE, REPLACE THE TEMPERATURE SENSOR.


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TEMPERATURE SENSOR RESISTANCE TEST PROCEDURE

FOR MICROLINK, MICROLINK 2 AND MICROLINK 2i CONTROLLED UNITS

BEFORE PROCEEDING, TURN UNIT OFF, OPEN CIRCUIT BREAKER(S),


Microlink

The temperature sensors change resistance with temperature. For a microprocessor-controlled unit they may be

either thermistors or RTD's. Temperature probes usually fail shorted or opens.

RTD probes are linear; meaning that the resistance change per degree is the same across the temperature range

RTD probes vary resistance from 91 ohms to 109 ohms and measure exactly 100 ohms at 32 F (0 C).

Additional temperature sensors may be found on most microprocessor units. They are thermistor type probes

but have a different shape than controlling or recording sensors. The compressor suction sensor (CPSS), the

ambient sensor (AMBS), the defrost temperature sensor (DTS) and the condenser saturation sensor (CSAS) wilmeasure 32,650 ohms at 32 F (0 C). The compressor discharge sensor (CPDS) will measure 326,500 ohms a

32 F (0 C).

Referring to the schematic and the wiring diagram, the RTS is connected to the Microlink microprocessor at the

PC connector through pins 11 and 20. Before measuring the RTS resistance, it is necessary to isolate it from the

circuit by disconnecting the PC plug from the I/O circuit board connection. After removing the plug, place the

ohmmeter probes in the plug at pins 11 and 20.

DO NOT TAKE ANY RESISTANCE MEASUREMENTS ON THE PC SOCKET MOUNTED ON THE

I/O CIRCUIT BOARD AS DAMAGE TO THE BOARD CAN RESULT.

It is necessary to know the temperature of the sensor before measuring its resistance. An accurate thermomete

can be placed near the sensor or the sensor can be placed in an ice bath. A temperature of 32 F (0 C) can be

obtained by ice bathing the sensor. A thermistor sensor will measure 32,650 ohms (CPDS will measure

326,500 ohms) and an RTD sensor will measure 100 ohms while in an ice bath.

Microlink 2 and Microlink 2i

To check the sensors on a Microlink 2 unit it is necessary to disconnect the EC connector from the back the

microprocessor module and take resistance readings at the EC plug. To check the sensors that attach to the

dataCORDER module it is necessary to disconnect the ED connector from the back of the dataCORDER

module and take resistance readings at the ED plug. Sensors are thermistor type. The temperature of the sensor

must be known before checking the resistance.


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TEMPERATURE CONTROL SIMULATOR MODULE PROCEDURE


WARNING: Do not remove or install any circuit board unless the START-STOP switch

is in the "0" or "OFF" position.

1. Install the manifold gauge set.

2. Remove the temperature control board and replace it with the temperature control simulator

module (TCSM).

3. Place all the TCSM switches (except the valve current switch) in the left (up or away from the

circuit board) position. Place the valve current switch in the center (off) position.

4. Turn the unit on by placing the START-STOP switch in the "ON" position. Check the 24 VAC

warning LED. If illuminated, turn the unit off and check all control wiring to the motherboard,

as this indicates a failure in the 24 VAC supply. If not illuminated, proceed to step 5.

5. At this time only the evaporator fans should be operating. If the unit is equipped with two-speed

evaporator fans, they should be operating in low speed. To test high-speed operation, move the

TU-1 switch to the down position.

6. To test the compressor and condenser fan circuit, move the TC switch to the down position.

The compressor and condenser fan motor should now be operating and the "Cool" lamp should

be illuminated.

7. With the compressor and condenser fan operating, you may test the suction modulation andquench valves. Move the valve (SMV) current switch to the 50% position. A decrease in

suction pressure should be noted. Move the valve current switch to the MAX position. The

suction pressure should drop into a vacuum. DO NOT leave the switch in the MAX position for

more than 30 seconds unless you move the TU-2 (TQ) switch to the down position. This should

energize the quench valve and you should note a slight increase in suction pressure. RETURN

ALL SWITCHES TO THEIR ORIGINAL POSITION.

8. To test the heater circuit, move the TH switch to the down position. The heater contactor and

"Heat" lamp should be energized. You may test the operation of the individual heaters by

measuring the current draw at the wiring loops provided below the heater contactor. Return the

TH switch to the original position and note that the heaters are turned off.

9. To test the operation of the defrost relay, move the DR switch to the down position. The

evaporator fans should turn off and the defrost lamp should be illuminated. Return the DR

switch to the original position. It will be necessary to turn the unit off to de-energize the DR

relay. The defrost relay will de-energize and the evaporator fans should re-start.


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10. To test the operation of the In-Range relay, move the In-Range switch to the right (down)

position. The In-Range lamp should be illuminated. Return the In-Range switch to the original

position. The In-Range relay will not de-energize unless you depress the TDS switch.

The following procedures require the use of a digital voltmeter.

11. To test the output of the 12 VDC circuit, place the positive voltmeter lead in test point TP1 and

the negative lead in TP4. The negative lead will remain in this position for the remainder of the

tests. A reading of 11.5 1.2 VDC should be noted on the meter.

12. To test the output of the 9 VDC circuit, remove the positive meter lead from TP1 and place it in

TP2. A reading of 8.5 to 9.5 VDC should be noted on the meter. This reading is the reference

voltage, which will be used in later steps. Make a note of this reading for use at that time. If a

reading of 12 VDC appears on the meter, re-check unit wiring.

13. To test the temperature set station place the positive meter lead in TP3. The test the selector, at

least three readings must be taken. For the first reading set the selector at one end of it's

operating range, for example, -20 C. Compare the reading to the SELECTOR SET POINTSIGNAL VOLTAGES chart on page 29 in the 69NT20/40 SERVICE TRAINING MANUAL.

Use the appropriate column based on the reference voltage measured in step 12. Repeat the test

with the selector at various setpoints throughout it's operating range. A good component will

display voltages very close to the chart value.

14. To test the temperature sensors it is first necessary to determine the temperature in the area

where the sensor is located. To test the supply temperature sensor, place the positive meter lead

in TP5. Compare the reading to the SENSOR D.C. VOLTAGES chart on page 27 in the

69NT20/40 SERVICE TRAINING MANUAL. For the return temperature sensor, move the

positive meter lead to TP6. A good sensor will display a voltage close to the chart value.

15. Turn unit off and re-install temperature control board.

AS THERE IS NO CALIBRATION ADJUSTMENT ON THE TEMPERATURE

CONTROL SYSTEM; DEFECTIVE COMPONENTS SHOULD BE REPLACED TO

INSURE ACCURATE TEMPERATURE CONTROL.


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MOTOR AND HEATER RESISTANCE TEST

ALL POWER SHOULD BE REMOVED FROM THE UNIT BEFORE PROCEEDING.

It is possible to test the static condition of all the motors and the heaters in the unit by reading the

resistance of the device at the contactor connections. All readings are taken at load side terminals.

If the unit is equipped with dual voltage by switch (VS), take the resistance readings with VS in both

the high voltage (460) and the low voltage (230) positions.

A resistance reading from each terminal to unit ground should also be taken to check for insulation

breakdown. An ohmmeter can be used but a more realistic reading can be taken using a Megger.

Meggers use high voltage, typically 500 VDC, while ohmmeters use 1 or 2 VDC.

TESTING THE COMPRESSOR

VS = 230 VS = 460

1 TO 2 ________ ________ 1 TO GND ________

1 TO 3 ________ ________ 2 TO GND ________

2 TO 3 ________ ________ 3 TO GND ________

TESTING THE CONDENSER FAN MOTOR

VS = 230 VS = 460

1 TO 3 ________ ________ 1 TO GND ________

3 TO GND ________

TESTING THE HEATERS

VS = 230 VS = 460

1 TO 2 ________ ________ 1 TO GND ________

1 TO 3 ________ ________ 2 TO GND ________

2 TO 3 ________ ________ 3 TO GND ________


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TESTING THE EVAPORATOR FAN MOTORS

VS = 230 VS = 460

1 TO 2 ________ ________ 1 TO GND ________

1 TO 3 ________ ________ 2 TO GND ________

2 TO 3 ________ ________ 3 TO GND ________


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MOTOR AND HEATER CURRENT TEST

It is possible to measure the operating current of all the motors and the heaters in the unit by using a

clamp on ammeter on the "wire loops" on the high voltage contactor connections at the load side

terminals. Current readings while operating on 230 VAC will be approximately 2 times readings for

460 VAC.

WHEN TAKING CURRENT READINGS WITH A CLAMP ON AMMETER, INSURE THAT

ALL LOOPS OF WIRE THAT ARE CONNECTED TO A CONTACTOR TERMINAL PASS

THROUGH THE CLAMP JAWS.

When running the unit in cool, it is possible to read the current drawn by the compressor, evaporator

fans and the condenser fan. The compressor current will depend on the position of the suction

modulation valve, pressures and temperatures. The heaters current can be measured while operating in

heat, defrost or dehumidification modes.

TESTING THE COMPRESSOR TESTING THE CONDENSER FAN MOTOR

VS = 230 VS = 460 VS = 230 VS = 460

1 ________ ________ 1 ________ ________

2 ________ ________ 3 ________ ________

3 ________ ________

TESTING THE HEATERS

VS = 230 VS = 460

1 ________ ________

2 ________ ________

3 ________ ________

TESTING THE EVAPORATOR FAN MOTORS

VS = 230 VS = 460

1 ________ ________

2 ________ ________

3 ________ ________


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REFRIGERANT CHARGE TESTING PROCEDURE

To insure proper refrigerating capacity, a refrigeration system must have the proper charge.

An under charged system may display low suction and discharge pressures. A semi-hermetic compressor may

overheat as cool refrigerant returning from the evaporator is used to cool the compressor motor. An under

charged system will have a low refrigerating capacity.

An over charged system may have extremely high discharge pressures. Pressures may be high enough to cause

system damage. The compressor discharge temperature may cause the oil to break down. Acids and sludge

formed by the oil break down may damage the compressor. An over charged system may also have a low

refrigerating capacity.

Before checking the refrigerant charge level on a 69NT20/40 container refrigeration unit, set the controller set

point to -13F (-25C) to ensure that the suction modulation valve is fully open. The unit must be running in

cool mode and the container temperature must be at 0 C (32 F) or below.

Partially block the condenser airflow and raise discharge pressure to at least 185 to 195 psig for R-12 and R-

134a. For high ambient temperatures this may not be necessary.

On units without a water-cooled condenser or a receiver, the sight glass/moisture indicator should be clear or

have an occasional bubble.

NOTE:DO NOT ADD REFRIGERANT JUST BECAUSE BUBBLES ARE SEEN IN THE SIGHT GLASS

THE ONLY SURE WAY TO TELL HOW MUCH CHARGE IS IN A UNIT IS TO REMOVE THE

REFRIGERANT AND WEIGH IT.

On units with a water-cooled condenser, the refrigerant level should be 1/2 the water-cooled condenser sight

glass.

On units with a receiver, there are 2 sight glasses. The bottom sight glass should not be empty and the top sigh

glass should not be full.


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REFRIGERANT CHARGING PROCEDURE

Refrigerant charging may be performed using one of two methods, fully charging an evacuated system and

partial charging.

FULLY CHARGING A REFRIGERATION SYSTEM

A refrigeration system needs to be fully charged if it is evacuated. A Carrier Transicold container refrigeration

system is fully charged using liquid refrigerant, through the liquid line valve (king valve) with the unit off.

Normally the full amount can be charged without warming the refrigerant container. With the refrigerant

container on a scale, carefully weigh in the correct amount. Connect the refrigerant container to the king

valve and purge the hose to remove any air. Midseat the king valve and open the refrigerant container liquid

valve (disposable refrigerant containers must be inverted). The correct refrigerant charge can be found on the

unit nameplate that is attached to the bulkhead at the left of the compressor.

PARTIAL CHARGING A REFRIGERATION SYSTEM

It is necessary to partially charge a refrigeration system when the refrigerant charge is found to be low, or the

complete charge could not be introduced into the unit as described above.

A partial charge is introduced into the system through the suction service valve in vapor form only. With

the refrigerant container on a scale, carefully weigh in a small amount and then recheck the charge

Connect the refrigerant container to the suction service valve and purge air from the hose. With the compressor

running, allow vapor refrigerant to enter the system.

When charging is completed, check the system charge using the correct procedure. Adjust as necessary.


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REMOVING EXCESS CHARGE

If a refrigeration system is found to contain an excess refrigerant charge the excess must be removed to insure

safe and proper operation.

Excess refrigerant is removed in liquid form through the king valve with the unit operating in cool mode and the

compressor running. Attach a refrigerant container to the king valve using a manifold gauge set. Connect the

high side hose to the king valve and the low side hose to the suction service valve. Midseat (open) the suction

service valve. The center hose is connected to the refrigerant container. Purge the hoses of air. PLEASE

FOLLOW LOCAL ENVIRONMENTAL LAWS WHEN REFERRING TO THESE INSTRUCTIONS

Midseat the king valve and only open the high side hand valve on the manifold gauge set. The low side hand

valve on the manifold gauge set must be Frontseated and closed. Open the valve on the refrigerant container and

allow the system high side pressure to force liquid refrigerant into the refrigerant container. With the refrigeran

container on a scale, carefully remove a small amount and then recheck the charge.

When the unit charge is correct, close the refrigerant container valve, backseat and close the king valve and

open both hand valves on the manifold gauge set. This will allow the compressor (the system should be

running in cool mode) to draw any liquid refrigerant from the hoses into the unit.

BE CERTAIN THAT THE REFRIGERANT CONTAINER IS THE REFILLABLE TYPE AND HAS

THE CAPACITY TO CONTAIN THE REFRIGERANT ABOUT TO BE ADDED TO IT'S

CONTENTS. REFRIGERANT CONTAINERS SHOULD NEVER BE FILLED MORE THAN 80% BY

VOLUME.

REFRIGERANT COLOR CODE SYSTEM

REFRIGERANT CYLINDER COLOR EXPANSION VALVECOLOR

R-12 WHITE YELLOW

R-22 GREEN GREEN

R-134a LIGHT BLUE BLUE

R-404a ORANGE ORANGE

R-500 YELLOW ORANGE

R-502 PURPLE PURPLE

RECOVERED APPROPRIATE COLOR W/YELLOW SHOULDER OR

GRAY W/YELLOW SHOULDER*

*RECOVERED REFRIGERANT CYLINDERS/DRUMS SHALL BE MARKED AS SHOWN

BELOW IN ONE INCH (25MM) OR LARGER LETTERS/NUMERALS:

RECOVERED REFRIGERANT ____ (ENTER NUMBER)


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REFRIGERANT RECOVERY PROCEDURE

DO NOT OPERATE AN R-134a COMPRESSOR IN A VACUUM AS LOSS OF LUBRICATION AND

COMPRESSOR DAMAGE CAN RESULT. PLEASE FOLLOW LOCAL ENVIRONMENTAL LAWS

WHEN REFERRING TO THESE INSTRUCTIONS.

Connect a manifold gauge set between the refrigeration unit and the Totalclaim unit. Connect the high side

hose from the manifold gauge set to the unit king valve (manual liquid line valve) and the low side hose from

the manifold gauge set to the compressor suction service valve. The center hose from the manifold gauge se

should have an in line sight glass and be connected to the Totalclaim unit at the bottom hose connection that is

designated as the "black" connection. The king valve and the suction service valve must be mid-seated and the

manifold gauge set hand valves must be front-seated, isolating the center hose from the low side and high side

connections.

If the refrigeration unit is operable, set the Totalclaim recovery system to "liquid" and "recovery" modes

(NOT RECOVERY PLUS) and press the start button. Mid-seatonly the high side hand valveon the manifold

gauge set to allow liquid refrigerant to flow from the king valve of the refrigeration unit, through the manifold

gauge set, to the Totalclaim unit. Running the refrigeration unit in cool mode while blocking the condenserairflow will raise pressure at the king valve and reduce recovery time appreciably. You may run the unit the

entire time you are extracting liquid refrigerant taking care that the compressor does not overheat. When there

is no more liquid being extracted (WATCH THE SIGHT GLASS IN THE CENTER HOSE), turn the

Totalclaim unit off and then back on and select "vapor" and "recovery" modes. When the high and low side

gauges read the same pressure, open the low side hand valve to allow the Totalclaim to draw from both hoses

connected to the unit.

The Totalclaim unit will stop automatically when the refrigerant has been recovered and the refrigeration unit

internal pressure is at a 4-inch mercury vacuum. This method will not remove the same amount as the

"recovery-plus" mode and can take from 10 to 20 minutes, depending upon pressure, temperature and how

much refrigerant is in the refrigeration unit.

IN HIGH AMBIENT TEMPERATURE (ABOVE 85 F), YOU MAY NOT BE ABLE TO GET THE

TOTALCLAIM UNIT TO COMPLETE THE RECOVERY PROCEDURE UNTIL THE TOTALCLAIM

COMPLETES A BOTTLE COOLING PROCEDURE. THIS MAY BE CAUSED BY HIGH STORAGE

BOTTLE PRESSURE. IN THIS CASE, THERE WILL BE NO WAY TO CIRCUMVENT BOTTLE

COOLING MODE AS THIS PROTECTS THE INTERNAL COMPRESSOR FROM DAMAGE. THIS WILL

HAPPEN MORE OFTEN WITH R-22 AND R-502, AS THEY HAVE HIGHER SATURATION

TEMPERATURES.

If the refrigeration unit is inoperableand has not been running for 24 hours, the refrigerant will have

dispersed evenly throughout the unit and will be mostly in vapor form at the king and suction service valves. Inthis case set the Totalclaim unit to "vapor" and "Recovery" modes (NOT RECOVERY PLUS) and open both

the low and high sides of the manifold gauge set. In an inoperable refrigeration unit some refrigerant may

migrate to the compressor crankcase and mix with the compressor oil. This refrigerant may be difficult to

remove and may not all be extracted. This can be seen by checking the level of the liquid in the compressor

sight glass. If the level is high, it may indicate refrigerant is mixed with the compressor oil.


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The Totalclaim unit will stop automatically when the refrigerant has been recovered and the refrigeration unit

internal pressure is at a 4-inch mercury vacuum. This method will not remove the same amount as the

"recovery-plus" mode and can take from 20 to 40 minutes, depending upon pressure, temperature and how

much refrigerant is in the refrigeration unit.


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REFRIGERATION SYSTEM EVACUATION AND DEHYDRATION PROCEDURE

Proper evacuation and dehydration procedures are imperative when servicing a refrigeration system to ensure

good performance and long compressor life.

The results of improper evacuation may be expensive repairs and loss of service. Non-condensable gases in the

system result in high discharge pressure; moisture may cause ice blockage at the expansion valve; moisture and

refrigerant may react to form an acid. High discharge pressures may cause high discharge temperatures. This

may cause refrigerants and oils to form sludge that can block refrigerant flow in the system or block lubrication

to the compressor bearings. Acid may cause copper plating of the bearing surfaces and eventual compressor

failure.

Proper evacuation begins with a well-maintained vacuum pump. A vacuum pump must be a two-stage pump

and have a rated capacity of three to five cubic feet per minute (CFM). A pump of this capacity is available

from Carrier Transicold Service Parts under part number 07-00176-01. The oil used in the pump will trap some

of the moisture that is removed from the refrigeration system. Moisture trapped in the oil reduces the vacuum

pump efficiency, as the oil is the sealing medium. If left in the pump for extended periods this moisture may

also cause damage to the seals and metal surfaces of the pump. To keep a vacuum pump in top condition

closely adhere to the manufacturer's maintenance recommendations. At minimum, every three times a vacuum

pump is used, the oil must be changed. Use only vacuum pump oil in vacuum pumps.

To assure good, fast evacuation of the system; use large diameter evacuation hoses. Evacuation hoses are

designed especially for this purpose. Standard charging hoses, like those used on the manifold gauge set, are

made to be very flexible and to minimize leaks under high pressures however, they are not made to prevent

leaks into the hose under vacuum. Evacuation hoses are available from refrigeration suppliers and must be used

for all connections during evacuation. Hoses should be kept as short as possible. The standard manifold gauge

set cannot be used for evacuation, as the internal body porting is too small for good flow at low pressures. A

large manifold gauge set made for evacuation can be used or attach a vacuum manifold directly to the vacuumpump as shown in the example.

The only way to ensure that a good evacuation has been achieved is through the use of a micron gauge

(electronic vacuum gauge). The compound gauge on a standard manifold is not acceptable. A micron gauge

measures the extremely low absolute pressures that are necessary for removal of moisture from the system. Use

of this gauge is essential in determining the quality of the vacuum. 500 microns, a figure used in evacuation, is

approximately 1/50 of an inch of mercury. This is impossible to read on a standard compound suction pressure

gauge. A micron gauge is available from you local refrigeration supplier.

Evacuation should be performed through three ports in the refrigeration system. On container refrigeration

units the hoses should be connected to the compressor suction and discharge service ports, and to the king valveservice port.

Evacuation Procedure #1 should be performed after a major system repair (e.g. compressor, evaporator, or

condenser replacement). After a minor system repair, (e.g.) replacement of a solenoid valve or the filter/drier

perform Evacuation Procedure #2.

Be sure to leak check your evacuation setup prior to evacuation. If hoses or seals leak, proper evacuation is

impossible. Repair any leaks found before beginning.


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Connect the hoses from the refrigeration unit to the evacuation manifold. A refrigerant recovery system is also

connected to the system. If the unit will be swept with dry nitrogen instead of refrigerant, the refrigerant

recovery machine will not be needed. A vacuum gauge thermistor is connected to the manifold gauge set

The compound gauge on the manifold gauge set will be used to monitor system pressure not vacuum. The

pump is attached as shown.

Before proceeding, it is a good idea to replace the filter drier with a section of copper tubing with the

appropriate fittings.

BOILING TEMPERATURE OF WATERAT CONVERTED PRESSURES

TEMPERATURE

IN F

TEMPERATURE

IN C

INCHES OF

VACUUM

MICRONS Pounds/Sq. In.

(PRESSURE)

212 100 0.00 759,968 14.696

205 96.1 4.92 535,000 12.279

194 90 9.23 525,526 10.162176 80 15.94 355,092 6.866

158 70 20.72 233,680 4.519

140 60 24.04 149,352 2.888

122 50 26.68 92,456 1.788

104 40 27.75 55,118 1.066

86 30 28.67 31,750 .614

80 26.7 28.92 25,400 .491

76 24.4 29.02 22,860 .442

72 22.2 29.12 20,320 .393

69 20.6 29.22 17,860 .34464 17.8 29.32 15,240 .295

59 15 29.42 12,700 .246

53 11.7 29.52 10,160 .196

45 7.2 29.62 7,620 .147

32 0 29.70 5,000 .092

21 -6.1 29.82 2,540 .049

6 -14.4 29.87 1,270 .0245

-24 -31.1 29.91 254 .0049

-35 -37.2 29.915 127 .00245

-60 -51.1 29.919 25.4 .00049

-70 -56.7 29.9195 12.7 .00024-90 67.8 29.9199 2.54 .000049


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EVACUATION PROCEDURE #1 (TRIPLE EVACUATION OR DOUBLE SWEEP)

1. Remove any remaining system refrigerant using a refrigerant recovery system.

2. Replace the filter-drier with a section of copper tubing with the appropriate fittings. This action

will help speed the evacuation procedure.

3. Connect the vacuum hoses, vacuum pump, and vacuum gauge and refrigerant recovery unit tothe refrigeration unit.

4. With the unit service valves closed (back seated) and the vacuum pump and the thermistor(vacuum gauge) valves open, start the pump and draw the manifold and hoses into a very deep

vacuum. Shut off the pump and check to see if the vacuum holds. This is to test the setup for

leaks.

5. Midseat the refrigeration system service valves.6. With the vacuum pump and the thermistor valves open, start the pump and evacuate to a

pressure below 2000 microns.

7. Close the vacuum pump valve; turn off the vacuum pump. Wait a few minutes to be sure that

the vacuum holds.

8. Close the thermistor valve; closing the thermistor valve protects the thermistor from damage.Break the vacuum with clean refrigerant or dry nitrogen. Raise the pressure to approximately 2

psig. Monitor the pressure with the compound gauge.

9. Remove the refrigerant using a refrigerant recovery system or discharge the nitrogen to theatmosphere.

10. REPEAT STEPS 6, 7, 8 and 9 one time.11. Remove the copper tubing and change the filter-drier. Evacuate to a pressure of 500 microns.

Check that the vacuum holds. If pressure rises, it may indicate that there is a leak or there is

moisture remaining in the system.

12. Charge the system with refrigerant to specification per normal charging procedures.

EVACUATION PROCEDURE #2 (ONE TIME EVACUATION)

1. Remove any remaining system refrigerant using a refrigerant recovery system.

2. Replace the filter drier before evacuating.

3. Install vacuum hoses, vacuum pump, and refrigerant recovery system and micron gauge on the

unit.

4. With the unit service valves closed (back seated) and the vacuum pump and the thermistor valves open

start the pump and draw the manifold and hoses into a very deep vacuum. Shut off the pump and check

to see if vacuum holds. This is to test the setup for leaks.

5. Start the pump and evacuate to a pressure of 500 microns.

6. Close the vacuum pump and the thermistor valves and turn off the pump. Check that the vacuum holds

If pressure rises, it may indicate that there is a leak or there is moisture remaining in the system.

7. Charge the system with refrigerant to specification per normal charging procedures.


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Page 44

EVACUATION

R12 with QV1. Refrigerant Recovery Unit2. Refrigerant Cylinder3. Evacuation Manifold4. Valve5. Vacuum Pump6. Electronic Vacuum Gauge

7. Liquid Line Valve8. Condenser Coil9. Suction Service Valve10. Compressor11. Discharge Service Valve12. Evaporator Coil

12

8

10

9

4 4

4

6

52


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Page 45

REFRIGERANT RECOVERY

R134a with QEV

1. Refrigerant Recovery Unit2. Refrigerant Cylinder3. Discharge Pressure Regulator4. Suction/Liquid Heat Exchanger5. Condenser Coil

6. Evaporator Coil7. TXV8. Liquid Line Valve9. Quench Expansion Valve

2

1

8

3

6

4

9

5

7


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Page 46

69NT40 DUAL VOLTAGE COMPRESSOR INTERNAL RESISTANCE READINGS

NOTE: THESE READINGS ARE FOR A MICROLINK CONTROLLED 69NT40

USING A DUAL VOLTAGE SINGLE SPEED 37 CFM COMPRESSOR AND R-12.

ALL READINGS ARE APPROXIMATE AND MAY VARY FROM UNIT TO UNIT

READINGS FOR A NEW COMPRESSOR OR A USED COMPRESSOR

THAT IS TOTALLY DISCONNECTED FROM UNIT WIRING

CPB-8 TO CPB-9 = 0 (internal motor protector)

CPA-1 TO CPA-2 = .8 RESISTANCE READINGS ARE APPROXIMATE

CPA-1 TO CPA-3 = .8

CPA-2 TO CPA-3 = .8

CPA-4 TO CPB-1 = .4

CPA-5 TO CPB-2 = .4

CPA-6 TO CPB-3 = .4

ERRONEOUS READINGS MAY INDICATE A DEFECTIVE COMPRESSOR OR

MISWIRED OR DEFECTIVE COMPRESSOR TERMINAL BLOCKS

THE RESISTANCE READINGS FOR ALL CPA OR CPB CONNECTIONS SHOULD BE

GREATER THAN 1 MEG TO GROUND.

READINGS WITH COMPRESSOR INSTALLED AND WIRED TO UNIT CONNECTIONS

(CIRCUIT BREAKERS OFF AND UNIT POWER DISCONNECTED)

VS SET TO 460V VS SET TO 230V

C21 TO C22 = 1.6 .4 NOTE: RESISTANCE READINGS MAY

C21 TO C23 = 1.6 .4 VARY GREATLY BECAUSE OF

C22 TO C23 = 1.6 .4 RESISTANCE OF THE VS

CONTACTS.

ERRONEOUS READINGS MAY INDICATE A DEFECTIVE COMPRESSOR, A

DEFECTIVE VS SWITCH OR WRONG OR DAMAGED UNIT WIRING

THE RESISTANCE READINGS FOR C21, C22 OR C23 SHOULD BE GREATER

THAN 1 MEG TO GROUND.


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230 Volt External Connections


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460 Volt External Connections


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Page 50


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SERVICE PROCEDURES CHECKLIST

NAME___________________________

COURSE DATE ___________________

LOCATION ______________________

The following is a list of the service procedures, which you must be capable of performing in order to complete

this course. You must demonstrate, to the instructor, your ability in each area prior to taking the practical fina

exam.

PROCEDURE COMPLETED

1. Manifold gauge set installation and removal procedure. ____

2. Low side pumpdown procedure. _____

3. Relay testing procedure. _____

4. O6DR compressor operation test procedure. _____

5. Compressor oil level test procedure. _____

6. Superheat test procedure. _____

7. Analog controller 30 second test procedure. _____

8. Modulation and elec. quench valve test procedure. (Analog) _____

9. Modulation and elec. quench valve test procedure. (Micro) _____

10. CSS resistance test procedure. (Analog control) _____

11. Sensor resistance test procedure. (Analog & micro) _____

12. Temperature control simulator module. (Analog control) _____

13. Motor and heater resistance test procedure. _____

14. Motor and heater current test procedure. _____

15. Refrigerant charge level test procedure. ____

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