IM-810 Page 1

Installation and Maintenance Manual IM-810

Group: Unitary

Part Number: IM-810

Date: August 2005

Supersedes: March 2005

SAH Air Handler1-1/2 to 5 Tons

© 2005 McQuay International

Page 2 IM-810

Table of ContentsMODEL NOMENCLATURE . . . . . . . . . . . . . . . . . . . . . . . . . 2INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Receiving Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Codes and Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Important Message to the Installer . . . . . . . . . . . . . . . . . . . . 3Important Message to the Owner . . . . . . . . . . . . . . . . . . . . 3Recognize Safety Symbols, Words, and Labels . . . . . . . . . . 3Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4GENERAL WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4ELECTRIC HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4HKR INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5For All Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6DUCTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6ELECTRICAL SUPPLY WIRE AND MOP . . . . . . . . . . . . . . 6Inspection of the Building Electrical Service . . . . . . . . . . . . . 6Wire Sizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Maximum Overcurrent Protection (MOP) . . . . . . . . . . . . . . . 7Electrical Connections – Supply Voltage . . . . . . . . . . . . . . . 7

Air Handler Only (Non-Heat Kit Models) . . . . . . . . . . . . . . . .7Air Handler With Non-Circuit Breaker Heat Kits . . . . . . . . . .7Air Handler With Heat Kits Containing a Circuit Breaker. . . .7Low Voltage Connections . . . . . . . . . . . . . . . . . . . . . . . . . . .7REFRIGERANT LINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Tubing Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Post Brazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Piping Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Evaporator Coil Metering Devices . . . . . . . . . . . . . . . . . . . . .7Conversion to Downflow. . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Conversion To Horizontal . . . . . . . . . . . . . . . . . . . . . . . . . . .9Condensate Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10ACHIEVING A 2% LOW LEAKAGE RATE . . . . . . . . . . . . .10Humidity Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Two-Stage Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10THERMOSTAT WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . .10Thermostats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Start-Up Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Regular Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

"McQuay" is a registered trademark of McQuay International.© 2005 McQuay International

"Illustrations and information cover the McQuay International products at the time of publication and we reserve the right to make changes in design and construction at any time without notice."

MODEL NOMENCLATURE

ModelSAH= Split Air Handler Unit

Nominal Capacity (tons)18 = 1-1/2 24 = 230 = 2-1/232 = 2-1/2 36 = 3 42 = 3-1/2 48 = 449 = 460 = 561 = 5

Future Use

Voltage/PhaseR = 208-230/1/60

Refrigerant MeteringF = FlowraterT = TXV

Vintage

SAH 018 A R F Y

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Table 1: Unit Nameplate Model Number Identifier

INTRODUCTIONGeneral DescriptionThese installation instructions cover the indoor installation of1-1/2 to 5 ton multi-position air handlers. See the product cat-alog for information regarding specifications applicable toyour model and accessories.

Receiving InspectionMcQuay products are carefully inspected prior to shipmentand the carrier has assumed responsibility for loss or damageupon acceptance of the shipment.

Upon receiving your shipment, check all items carefullyagainst the Bill of Lading. Inspect the unit and/or accessoriesfor shipping damage as soon as they are received. Immedi-ately file claims for loss or damage, either shipping or con-cealed, with the shipping company.

Check the unit nameplate to verify the model number and elec-trical characteristics are correct. In the event an incorrect unitis shipped, it must be returned to the supplier and must NOTbe installed. The manufacturer disclaims all responsibility forthe installation of incorrectly shipped units.

Codes and RegulationsThis product is designed and manufactured to permit installa-tion in accordance with National Codes. System designshould, where applicable, follow information presented inaccepted industry guides such as the ASHRAE Handbooks. Itis the installer' s responsibility to install the product in accor-dance with National Codes and/or prevailing local codes andregulations. The manufacturer disclaims all responsibility forequipment installed in violation of any code or regulations.

Important Message to the InstallerThis equipment is to be installed by an experienced installationcompany and fully trained personnel. Carefully read allinstructions and take into account any special considerationsprior to installing the unit. Give this manual to the owner andexplain its provisions.

Important Message to the OwnerRead these instructions carefully and keep them near the prod-uct for future reference. Although these instructions areaddressed primarily to the installer, useful maintenance infor-mation is included. Have the installer acquaint you with theoperation of the product and periodic maintenance require-ments.

Recognize Safety Symbols, Words, and LabelsThe following symbols and labels are used throughout thismanual to indicate immediate or potential hazards. It is theowner's and installer's responsibility to read and comply withall safety information and instructions accompanying thesesymbols. Failure to heed safety information increases the riskof property damage and/or product damage, serious personalinjury or death. Improper installation, operation and mainte-nance can void the warranty.

Unit Nameplate McQuay Model NumberARUF018-00A-1/-1A SAH018ARFYARUF024-00A-1/-1A SAH024ARFYARUF030-00A-1/-1A SAH030ARFYARUF032-00A-1/-1A SAH032ARFYARUF036-00A-1/-1A SAH036ARFYARUF042-00A-1/-1A SAH042ARFYARUF048-00A-1/-1A SAH048ARFYARUF049-00A-1/-1A SAH049ARFYARUF060-00A-1/-1A SAH060ARFYARUF061-00A-1/-1A SAH061ARFY

ARPT024-00C-1/00C-1A SAH024ARTYARPT032-00C-1/00C-1A SAH032ARTYARPT036-00C-1/00C-1A SAH036ARTYARPT042-00C-1/00C-1A SAH042ARTYARPT049-00C-1/00C-1A SAH049ARTYARPT061-00C-1/00C-1A SAH061ARTY

IMPORTANT

The United States Environmental Protection Agency (EPA) regulations cover introduction and disposal of refrigerants in this unit. Failure to follow those regulations can harm the environment and lead to substantial fines. Because regulations can change, a certified technician should perform any work done on this unit. If you have any questions, please contact the local office of the EPA.

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Replacement PartsReplacement parts can be obtained by contacting McQuay at1-800-37-PARTS. When contacting McQuay for service orreplacement parts, refer to the model number and serial num-ber of the unit as stamped on the nameplate attached to theunit.

GENERAL WARNINGS

PRODUCT DESCRIPTIONThese air handlers are designed to be installed in upflow,downflow, and horizontal right orientations.

These air handlers are designed for indoor use only and mustonly be installed in a weatherized area. DO NOT INSTALLOUTDOORS. Typical installations for this product include:

• Overhead (attic/mezzanine, etc.)• Closet/mechanical room/basement/crawl space.

Other applications are acceptable, provided they comply withthis manual and local/state codes.

When matched with a McQuay brand condenser or heat pump,an ARI certified rating is available for many combinations.

Electric heat is available for all models. This is an accessoryand is not provided with the equipment. Use only the electricheat kits identified in the “Electric Heat” section of this man-ual.

These air handlers are intended for use with a room thermostat.The thermostat is not supplied with this equipment. Thermo-stats that use 24 VAC operating voltage must be used.

ELECTRIC HEAT

This air handler does not have factory-installed electric heat.Electric heat is available as an accessory. If installing thisoption, only the HKR series heat kits can be used. See theproduct catalog to determine the HKR Kit applicable to yourair handler and application.

The heating mode temperature rise is dependent upon the sys-tem airflow, the supply voltage and the heat kit size (kW)selected. Use Tables 2-4 to determine the temperature rise (oF).

DANGERImmediate hazards which WILL result in property damage, product damage, severe personal injury and/or death.

WARNINGHazards or unsafe practice CAN result in property damage, product damage, sever personal injury and/or death.

CAUTIONHazards or unsafe practices which CAN result in property damage, product damage, and/or per-sonal injury.

DANGERCARBON MONOXIDE (CO) POISONING HAZARD

CO can cause brain damage and death. It is odorless and colorless. The installation area must be properly vented and joints must be tight so CO cannot enter ductwork or enclosed space.

WARNINGBefore servicing or installing this equipment, the electrical power to this unit must be in the "OFF" position. More than one disconnect may exist. Failure to disconnect power can cause electrical shock, serious personal injury or death.

WARNINGThe unit must have an uninterrupted, unbroken electrical ground. Failure to properly ground can cause severe personal injury or death.

WARNINGInstallation and service by trained, qualified technicians only. High pressure and electricity can cause severe personal injury or death. Observe ALL warnings contained in this manual and the labels/tags attached to the equipment.

WARNINGThis product is factory shipped for use with a 208-230/1/60 electrical power supply. This air handler must not be reconfigured to operate with any other power supply. Failure to observe this warning may result in personal injury, equipment damage and fire.

WARNINGWhen installing or servicing this equipment wear protective gloves, gear and eyeware. Also observe special safety requirements (hard hats etc.).

WARNINGTo avoid personal injury, fire and property damage, refer to the “Installing Electric Heat” section of this manual for the correct installation procedure.

WARNINGThe electrical characteristics of the air handler, the electric heat kit, and the supply power must agree.

Failure to observe this warning can result in equipment damage, fire and property damage.

IM-810 Page 5

Table 2: 230/1/60 Supply Voltage Temperature Rise (°F)

Table 3: 220/1/60 Supply Voltage Temperature Rise (°F)

Table 4: 208/1/60 Supply Voltage Temperature Rise (°F)

Note: For installations not indicated above, the followingformula is to be used:

TR = (kW x 3412) x (Voltage Correction) x 1.08 / CFM

Where:TR = Temperature Rise KW = Heat Kit Actual kW 3412 = Btu per kW

Voltage Correction =.96 (230 Supply Volts) =.92 (220 Supply Volts) =.87 (208 Supply Volts)

1.08 = Constant CFM = Measured Airflow

Note: The Temperature Rise Tables can also be used todetermine the air handler airflow delivery. Whenusing these tables for this purpose set the room ther-mostat to maximum heat and allow the system toreach steady state conditions. Insert two thermome-ters, one in the return air and one in the supply air.The temperature rise is the supply air temperatureminus the room air temperature.

HKR INSTALLATION

Follow these instructions when installing the HKR kit. Per-form steps 1 through 7 in an open area, before moving the airhandler to its final installation position.For All Models1. Turn off the electrical supply to the unit.2. Remove the upper access panel.3. Remove the screws that attach the electric heat block-off

panel. Retain these screws. Discard the block-off panels.4. If the heat kit is equipped with circuit breakers (“C” mod-

els), remove the circuit breaker mounting bracket, leavingthe circuit breakers attached.

5. Slide the heater kit into the slot left vacant from step 3 andsecure using the screws removed in step 3. Verify that theheater is installed with the airflow directional label pointingin the direction of the discharge air. Steps 6 through 8 andStep 11 relate to circuit breaker models only. For kits thatdo not contain circuit breakers, perform Steps 9-10 and 12through 14.

6. Install the circuit breaker mounting panel on the upperright area of the blower deck. Insert screws through theblower deck into the mounting panel from the blower side.The plastic mounting pin on the side of the mounting panelis inserted into a receiving hole on the side of the air han-dler cabinet.

CFMHeat Kit Nominal kW

3 5 6 8 10 15 20 21600 18 28 35 41800 13 21 26 31 42

1000 11 17 21 25 34 501200 9 14 18 21 28 42 56 621400 8 12 15 18 24 36 48 531600 7 10 13 15 21 31 42 461800 6 9 12 14 19 28 37 412000 5 8 11 12 17 25 34 37

CFMHeat Kit Nominal kW

3 5 6 8 10 15 20 21600 17 27 34 39800 13 20 25 30 40

1000 10 16 20 24 32 481200 8 13 17 20 27 40 53 591400 7 11 14 17 23 34 46 511600 6 10 13 15 20 30 40 441800 6 9 11 13 18 27 36 392000 5 8 10 12 16 24 32 35

CFMHeat Kit Nominal kW

3 5 6 8 10 15 20 21600 16 25 32 37800 12 19 24 38 38

1000 10 15 19 22 30 461200 8 13 16 19 25 38 51 561400 7 11 14 16 22 33 43 481600 6 9 12 14 19 28 38 421800 6 8 11 12 17 25 34 372000 5 8 10 11 15 23 30 34

DANGERCARBON MONOXIDE (CO) POISONING HAZARD

CO can cause brain damage and death. It is odorless and colorless. The installation area must be properly vented and joints must be tight so CO cannot enter ductwork or enclosed space.Do not operate this product without all ductwork attached.

WARNINGVerify that all power is disconnected prior to attempting installation of this heater kit. There may be more than one disconnect servicing this equipment.• When installed in a garage, the elements must be at

least 18" above the floor.• Strain relief and conductor protection must be pro-

vided at the supply wire entrance.• This appliance must be installed following the ANSI/

NFPA70 (National Electrical Code) and other appli-cable codes. If in doubt, contact the local authority having jurisdiction.

• Use copper conductors only• Some localities require the installer be licensed.

Contact the local authority if in doubt.

Failure to follow these instructions can cause fire, electrical shock, property damage, personal injury or death.

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7. The circuit breaker is to be installed in the correct orienta-tion (i.e. the OFF position is down). In downflow applica-tions, remove the circuit breaker from the mounting bracketand install it 180o from the factory direction. Upflow andhorizontal installations require no position changing.Installation Tip: In some cases it may be easier to wire thebreakers before reinserting them into the mounting panel.

8. Following the HKR wiring diagram, insert the electricalsupply wiring into the lugs provided on the circuit breakerand tighten. THE ELECTRICAL SUPPLY WIRES MUSTBE ROUTED THROUGH A MEANS OF STRAINRELIEF AS THEY ENTER THE CABINET.

9. Remove the multi-pin connector with the jumper wire anddiscard. Insert the new wiring harness provided with thekit. Note: the plug is keyed and can only be installed inone direction.

10.Insert the supply wire ground conductor into the lug pro-vided with the kit. Verify that this connection is tight.

11. Break out the appropriate area(s) of the plastic circuitbreaker cover on the air handler front panel. Rotate thispanel for downflow applications.

12.The air handler supply wiring and low voltage wiring is tobe connected as shown on the HKR wiring diagram.

13.Install upper access panel removed in step 2.14.Apply the wiring diagram over the original air handler wir-

ing diagram.

LOCATION

When installing this air handler, give careful consideration tominimizing the length of refrigerant tubing. Do not install theair handler in a location either above or below the condenserthat violates the instructions provided with the condenser.Allow a minimum of 24" in front of the unit for service clear-ance. When installing in an area directly over a finished ceiling(such as an attic), an emergency drain pan is required directlyunder the unit. See local and state codes for additional require-ments. When installing this unit in an area that may becomewet, elevate the unit with a sturdy, non-porous material. Ininstallations that may lead to physical damage, install a protec-tive barrier to prevent equipment damage.

DUCTWORKThis air handler is designed for a complete supply and returnductwork system. For proper system performance, size the ductwork to accom-modate 375-425 CFM per ton of cooling with a static pressurenot to exceed 0.5" WC. Inadequate ductwork that restricts air-flow can result in improper performance and compressor orheater failure. Construct ductwork in a manner that limitsrestrictions and maintains suitable air velocity. Seal ductworkto the unit in a manner that will prevent leakage.Return Ductwork. DO NOT TERMINATE THE RETURNDUCTWORK IN AN AREA THAT CAN INTRODUCETOXIC OR OBJECTIONABLE FUMES/ODORS INTO THE

DUCTWORK. The return ductwork is to be introduced intothe air handler bottom (upflow configuration).

Return Air Filters. Each installation must include a returnair filter. This filtering may be performed at the air handler orexternally using a return air filter grille. Air handlers mountedin the downflow orientation require external filtering. A wash-able filter is available as an accessory. For optimum perfor-mance, frequent filter cleaning is advised. Refer to Table 5 forthe appropriate filter.

Table 5: Filter Selections

ELECTRICAL SUPPLY WIRE AND MOP

The unit must have an uninterrupted, unbroken electrical ground.The electrical ground circuit may consist of an appropriatelysized electrical wire connecting the ground lug in the unit con-trol box wire to the building electrical service panel. Othermethods of grounding are permitted if performed in accor-dance with the National Electric Code (NEC)/AmericanNational Standards Institute (ANSI)/National Fire ProtectionAssociation (NFPA) 70 and local/state codes. In Canada, elec-trical grounding is to be in accordance with the Canadian Elec-tric Code CSA C22.1. Failure to observe this warning canresult in electrical shock that can cause serious personal injuryor death.Inspection of the Building Electrical ServiceThis unit is designed for single-phase electrical supply. DONOT OPERATE ON A THREE-PHASE POWER SUPPLY.Measure the power supply to the unit. The supply voltagemust be in agreement with the unit nameplate power require-ments and within the range shown in Table 6.

WARNINGThis air handler is not weather tight and is designed for indoor installation only. Do not install outdoors.

DANGERCARBON MONOXIDE (CO) POISONING HAZARD

CO can cause brain damage and death. It is odorless and colorless. The installation area must be properly vented and joints must be tight so CO cannot enter ductwork or enclosed space.Do not operate this product without all ductwork attached.

SAH Model Filter Number Qty. Required018-032 FIL18-32 1036-042 FIL36-42 1048-061 FIL48-61 1

WARNINGTo avoid the risk of fire or equipment damage, use only copper conductors. Before servicing or installing this equipment, the electrical power to this unit must be in the “off” position and all power supplies disconnected. More than one disconnect can exist. Failure to observe this warning can result in an electrical shock that can cause personal injury.

WARNINGThe unit must have an uninterrupted, unbroken electrical ground. Failure to properly ground can cause severe per-sonal injury or death.

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Table 6: Minimum and Maximum Supply Voltage

Wire SizingWire size is important to the operation of your equipment. Usethe following checklist when selecting the appropriate wiresize for your unit.

• Wire size must carry the Minimum Circuit Ampacity(MCA). The unit MCA for the air handler and the optionalelectric heat kit can be found on the unit nameplate.

• Wire size allows for no more than a 2% voltage drop fromthe building breaker/fuse panel to the unit. Refer to the lat-est edition of the National Electric Code, or the CanadianElectric Code (Canada) when determining the correct wiresize. Table 7 shows the current carrying capabilities forcopper conductors rated at 75oC with a 2% voltage drop.Use Table 7 to determine the voltage drop per foot of vari-ous conductors.

Table 7: Maximum Allowable Length in Feet to Limit Voltage Drop to 2%*

*Based on NEC 1996

Maximum Overcurrent Protection (MOP)Every installation must include an NEC (USA) or CEC (Can-ada) approved overcurrent protection device. Also, check withlocal or state codes for special requirements.

This protection can be in the form of fusing or HACR style cir-cuit breakers. The nameplate can be used as a guide for select-ing the MAXIMUM overcurrent device.

Note: Fuses or circuit breakers are to be sized larger thanthe equipment MCA, but not to exceed the MOP.

Electrical Connections – Supply VoltageUSE COPPER CONDUCTORS ONLY.

A knockout is provided on the air handler top panel or side toallow for the entry of the supply voltage conductors. An NECor CEC approved strain relief is to be used at this entry point.The wire is to be sized in accordance with the “Electrical Wireand MOP” section of this manual. Some areas require the sup-ply wire to be enclosed in conduit. Consult your local codes.

Air Handler Only (Non-Heat Kit Models)The building supply connects to the stripped black and whitewires contained in the air handler electrical compartment cav-ity. A ground screw is also contained in this area. Attach thesupply wires to the air handler conductors as shown in the unitwiring diagram using appropriately sized solderless connectorsor other NEC or CEC approved means.

Air Handler With Non-Circuit Breaker Heat KitsA terminal block is provided with the HKR kit to attach thesupply and air handler connections. Follow the installation

instructions and wiring diagram provided with the HKR heatkit for complete wiring details.

Air Handler With Heat Kits Containing a CircuitBreaker. HKR models with a “C” suffix contain a circuit breaker(s).The air handler has a plastic cover on the access panel that willrequire either one or both sections to be removed to allow theheat kit circuit breaker(s) to be installed. See the HKR Instal-lation Instructions for further details. The air handler wires andsupply wires are installed directly onto the HKR circuitbreaker(s) as shown in the HKR Installation Manual and wir-ing diagram.

Low Voltage ConnectionsSeveral combinations of low voltage arrangements are avail-able, depending on the presence of a heat kit and whether theheat kit is single or multi-stage. The low voltage connectionsare determined by whether the outdoor unit is a condenser orheat pump. The 24V-control voltage connects the air handlerto the room thermostat and condenser. Use copper conductorsfor low voltage wiring. A minimum of 18AWG must be usedfor installations up to 50 feet and 16AWG for installations over50 feet. Low voltage wiring can be made through the top ofthe cabinet or through either side. See the “Thermostat Wir-ing” section of this manual for typical low voltage wiring con-nections.

REFRIGERANT LINES

Tubing PreparationAll cut ends are to be round, burr free, and cleaned. Failure tofollow this practice increases the chances for refrigerant leaks.The equipment suction line(s) are spun closed and require pipecutters to cut off the closed end.Use solder with a minimum of 5% silver.Post BrazingQuench all welded joints with water or a wet rag.Piping SizeFor the correct size tubing, follow the specification for the con-denser/heat pump.

Evaporator Coil Metering DevicesFlowrater ModelFor most installations, no change to the flowrater orifice isrequired. In mix-matched applications (the condenser/heatpump is a different tonnage than the air handler), a differentflowrater orifice may be required (Figures 1 and 2). See thepiston kit chart in the Condensing Unit Catalog. Consult yourlocal representative for the details regarding mix-matched ori-fice sizing.

Nominal Input Minimum Voltage Maximum Voltage208/230 187 253

Wire Size (AWG)

Min. Circuit Ampacity (MCA)10 15 20 25 30 35 40 45

14 75 50 37 NR NR NR NR NR12 118 79 59 47 NR NR NR NR10 188 125 95 75 63 54 NR NR8 301 201 150 120 100 86 75 686 471 314 235 188 157 134 118 110

CAUTIONWhen welding close to the painted surfaces, use a quenching cloth to prevent scorching or marring of equipment finish.

WARNINGThis coil is shipped under pressure. Follow instructions included in this manual (pages 8 and 9) to avoid personal injury.

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1. Loosen the 13/16" nut 1 TURN ONLY. No pressure lossindicates a possible leak.

2. Remove the nut and discard the black or brass cap.3. Remove the check piston to verify it is correct. See the pis-

ton kit chart in the Condening Unit Catalog.4. Use a tube cutter to remove the spin closure on the suction

line.5. Remove the tailpiece clamped to the exterior.6. Slide the 13/16" nut into position. Braze the tailpiece to the

liquid tube.7. Insert the suction line into the connection. Slide the insula-

tion and the rubber grommet at least 18" away from thebraze joint.

8. AFTER THE TAILPIECE HAS COOLED, position thewhite Teflon seal and hand tighten the nut.

9. Torque the 13/16" nut to 20-30 ft-lbs. [2.77-4.15 meter kg]. 10.Replace the suction line grommet and insulation.Figure 1. Replacing Flowrater Orifice

Figure 2. Suction Line

TXV Model

IMPORTANT: The sensing bulb is not permanently installedin the factory. To prevent damage, remove this bulb prior tobrazing. Place it in the proper location after the braze joint hascooled (Figure 3).1. Loosen the 13/16" nut 1 TURN ONLY. No pressure loss

indicates possible leak.

2. Remove the nut and discard the black or brass cap.3. Remove the large front panel and remove the sensing bulb

from suction manifold. TO PREVENT DAMAGE TO THESENSING BULB, VERIFY THAT THE BULB IS NOTNEAR THE FLAME OR IN CONTACT WITH THE SUC-TION LINE OR MANIFOLD DURING BRAZING.

4. Use a tube cutter to remove the spin closure on the suctionline.

5. Remove the tailpiece clamped to the exterior.6. Slide the 13/16" nut into position (Figure 1). Braze the tail-

piece to the liquid tube.7. Insert the suction line into the connection. Slide the insula-

tion and the rubber grommet at least 18" away from thebraze joint.

8. AFTER THE TAILPIECE HAS COOLED, position thewhite Teflon seal and hand tighten the nut.

9. Torque the 13/16" nut to 20-30 ft-lbs. [2.77-4.15 meter kg].

10.Replace the sensing bulb to the horizontal portion of thesuction line (Figure 3), just inside cabinet. Place the bulbparallel with suction line in the 10 o’clock position. If the10 o’clock position is inaccessible, place in the 2 o’clockposition. Secure the bulb to the line with strapping pro-vided in the literature envelope. Insulate the sensing bulbto the line with self-adhesive insulation provided in theenvelope.

11. Replace the access panel, suction line grommet, and insula-tion.

Figure 3. Sensing Bulb Location

For the majority of installations, no adjustment to the TXV set-ting is required. However, if the measured superheat is lessthan 8°F or greater than 20°F, an adjustment is required. Theadjustment stem is at the base of the valve (opposite the dia-phragm) under the flare nut.

To increase the superheat (measured at the condenser basevalve), turn the stem clockwise (in). To decrease the superheat,turn the stem counterclockwise (out). Use a ¼" refrigerationwrench for this function.

Note: Design point for the system is 10°F of superheat(measured at the condenser base valve) at 95°F out-door air.

Charging Note: Air handlers with a TXV should be charged to15°F of subcooling at the indoor inlet. This supercedes any sub-cooling value listed in the condensing unit literature.

Conversion to DownflowPerform the conversion to downflow before placing the airhandler in its final location. The location must allow for accessto all sides. To prevent the evaporator coil pan from “sweat-ing,” use the DPI accessory insulation kit when performingthis conversion. Note: The DPI kit is not supplied with thisproduct and must be purchased separately. See Table 8 forthe correct DPI kit.Table 8:

SAH Model Insulation Kit018-032 DPI18-302036-042 DPI36-422048-061 DPI48-612

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Refer to Figures 4 through 6 for the location of the compo-nents referenced in the following steps. Figure 4 illustrates thenew installation location for the removed components.1. Before inverting the air handler, remove all access panels,

the coil rear channel bracket, and the filter close-off panel.2. Remove the evaporator coil and the horizontal drain pan.

Discard the horizontal drain pan.3. Install the provided plastic plug into the vacated access

panel.4. Remove the two (2) zee coil support brackets and insula-

tion retaining brackets.5. Remove the tie bracket.6. Install the DPI Insulation Kit onto the bottom of the drain

pan.Figure 4. Removed Componants Locations

7. Install the zee coil supports and the wrapper stiffeners.8. Install the tie bracket.9. Install the rear channel bracket.10.To prevent possible condensate “blow off”, lay the insula-

tion retainers into the evaporator coil pan as shown in Fig-ure 5.

Figure 5. Insulation Retainers

To complete the conversion, slide the evaporator coil into thechassis and attach the three (3) access panels. (Figure 6).

Figure 6. Conversions to Downflow

Conversion To HorizontalThe following describes converting to “Horizontal Left-Hand”. The only field modification required for conversion to“Horizontal Right-Hand” is the removal of the plastic knock-outs in the horizontal panel drain connections.

The conversion to horizontal left-hand (Figure 7) should beperformed before placing the air handler in its final location,and in an area that allows for access to all sides.

1. Remove the (3) air handler access panels.

2. Remove the “J” shaped bracket that retains the evaporatorcoil.

3. Remove the flowrater (or TXV) from the lower left sideaccess panel and slide out the evaporator coil and horizon-tal drain pan.

4. Remove the gasket from the horizontal pan drain connec-tions.

5. Remove the oval shaped plastic plug from the left sideaccess panel. Remove the oval shaped rubber gasket sealfrom the lower right side access panel.

6. The drain connections for the horizontal pan are sealedwith a thin coating of plastic. Carefully knock out thisplastic seal with a screwdriver and hammer.

Note: The upper drain will become the secondary drainwhich is mandatory in many municipalities .

7. Install the plastic plug removed in step 5 in the right sidelower access panel and the oval shaped rubber gasket in thelower left access panel.

8. Reinstall the evaporator coil with the horizontal panel onthe left side. Note: Push the assembly completely to therear to verify the engagement of the upflow pan with therear channel bracket.

NOTE: The filter provision is not applicable inthis downflow application.

TOP OF WRAPPER

INSULATION JACKET

ZEE COIL SUPPORT

WRAPPER STIFFENER

DRAIN PAN INSULATIONDPI KIT (HATCHED AREA)

BLOWER

NEOPRENE GASKET

MOTOR

Page 10 IM-810

9. Install the “J” bracket (removed in step 2) to support theupflow pan to the tie channel.

10.Attach all panels and the refrigerant management device.

Figure 7. Conversion to Horizontal Left-Hand

Condensate RemovalThe drain pan has a primary and secondary drain connection(Figure 7). Condensate removal is performed by attaching a¾” PVC pipe to the evaporator coil pan and terminated inaccordance with local or state codes. The installation mustinclude a “P” style trap that is located as close as possible tothe evaporator coil. To prevent possible damage to the evapo-rator drain pan do not over-tighten the drain connection(s).See Figure 8 for an illustration of a typical condensate line “P”trap.

Installations that are above a finished ceiling may require afield-supplied auxiliary drain pan. Consult local codes on thisrequirement.

Figure 8.

Use of a condensate removal pump is permitted when neces-sary. This condensate pump should have provisions for shut-ting off the control voltage in the event of the drain becomingblocked. A trap must be installed between the unit and the con-densate pump. IMPORTANT: The evaporator coil is coated with oils thatmay dissolve Styrofoam and certain types of plastics. Aremoval pump or float switch must not contain any of thesematerials.Installation Tip: Priming the “P” trap may avoid improperdraining at the initial installation and at the beginning of thecooling season.

ACHIEVING A 2% LOW LEAKAGE RATEVerify that the Neoprene gasket with PSA remains intact on allsurfaces where the access panels are secured. These surfacesare the entire length of the wrapper and areas between theupper tie plate, and the upper and lower access panels. Verifythat the upper access panel breaker insert gasket is intact, and

that the flowrator gasket is installed on the lower access panel.An additional drain hole cover is required.

HUMIDITY CONTROLWhen using a Humidistat (normally closed), cut jumper PJ6 onthe control board. The Humidistat will only affect cooling air-flow by adjusting the airflow to 85%.

TWO-STAGE HEATINGWhen using staged electric heat, cut jumper PJ4 on the controlboard.

THERMOSTAT WIRINGUse the thermostat wiring diagram (Figures 9 thru 12) andthose provided with the thermostat when making connections. Figure 9. Low Voltage Wiring Diagram for Cooling Unit WithOptional Heat Kit (10KW and below)

Figure 10. Low Voltage Wiring Diagram for Cooling Unit WithOptional Heat Kit (15KW and above)

ThermostatsNote: Second stage heat can be accomplished by using a

multi-stage heating thermostat or using an outdoorthermostat as shown in Figures 11 and 12.

McQuay part number CHT18-60 is a single-stage cool and sin-gle-stage heat thermostat.McQuay part number HPT18-60 is a single-stage cool, two-stage heat pump thermostat. The first stage is heat pump heat-ing and the second stage is optional electric heat.If additional features are desired, such as digital or program-mable capabilities, these thermostats are commercially avail-able. Follow the thermostat manufacturer’s instruction forinstallation.

IM-810 Page 11

Start-Up Procedure• Prior to start-up, verify that all electrical connections are

properly sized and tightened.• All panels must be in place and secured. For air tight appli-

cation, neoprene gasket must be positioned at prescribedlocations to achieve 2% leakage.

• The tubing must be leak free.• The unit should be elevated, trapped and pitched to allow

for drainage.• The low voltage wiring is connected.• The auxiliary drain is installed, when necessary, and

pitched to allow for drainage.• The drain pan and drain tubing has been leak checked. • The return and supply ducts are sealed.• The unit is elevated when installed so water cannot accu-

mulate. • No flammable vapors can be present.

• The unit is protected from vehicular or other physical dam-age.

• The return air is not obtained from any areas where theremay be objectionable odors, flammable vapors or productsof combustion such as carbon monoxide (CO), which maycause serious personal injury or death.

Regular Maintenance

The only item to be maintained on a regular basis by the user isthe circulating air filter(s). Filters should be cleaned orreplaced regularly. A certified service technician must per-form all other services.

Figure 11. SAH 1-1/2 to 5 Ton System Composite Diagram - 10 kW and Below

WARNINGTo avoid electrical shock and personal injury, disconnect all power supplies before performing any service. Note that there may be more than one power supply.

Heat Pump

C W2 O Y R RCY O W2 G E

ConventionalRoom Thermostat

BLW

ORY

R

BL

W

OR

Y

RR

GR

W

BRBL

BL

#18 GA. 5 Wire

#18 GA. 7 Wire

Pink

Outdoor Thermostat(optional) Make On Fall

#18GA. 6 Wire Needed When Outdoor Thermostat Is Used

SeeNote 3

Page 12 IM-810

Figure 12. SAH 1-1/2 to 5 Ton System Composite Diagram - Above 10 kW

BL

BR

C W2 O Y R RCY O W2 G E

#18 GA. 5 Wire

#18 GA. 7 WireConventional

Room ThermostatHeat Pump

RR

RY

ORW

BL

BL

W

OR

Y

W

GR

EHR

OT1

OT2

#18GA. 7 Wire Needed When 2 Outdoor Thermostat Are Used

Pink

AR Indoor Unit

Note

SeeNote 3

SeeNote 2

NOTES:1. Outdoor Thermostat (OT1) should be the first to close and the first to open.2. Install jumper if Outdoor Thermostat (OT2) is not used. 3. Remove wire when using Outdoor Thermostat. #18 Ga. 7 wire needed when (2) OTs are used.

NOMENCLATURE :OT - Outdoor Thermostat (Optional)MOF - Make On FallEHR - Emergency Heat Relay (Optional)

COLOR CODESR - Red OR - OrangeY - Yellow W - WhiteBL - Blue G- GreenBR - Brown

1 2

34

This document contains the most current product information as of this printing. For the most up-to-date product information, please go to www.mcquay.com.

www.mcquay.com • 800-432-1342