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SECTION VII
H.V.A.C SPECIFICATION
PACKAGED TYPE AIR-CONDITIONING UNITS AIR COOLED
(DATA SHEET ATTACHED MUST BE FILLED & SUBMITTED WITH OFFER)
The units, with capacities as per Bill of Quantities, should be factory assembled and
tested prior to dispatch to site.
Units should be packaged type with indoor unit housing evaporator coil, blower, filters,
panel & compressors; and outdoor unit housing the condensers and fans.
Mounting & Discharge:
The indoor units should be enclosed in a cabinet fabricated out of pre-coated / pre-plasticized / polymer coated / powder coated sheet steel panels. The panels should be
easily removable for inspection/ maintenance. The panels should be mounted on frame
with proper gaskets (neoprene rubber / other grade on approval) to avoid dustaccumulation, noise / vibrations & air leakages. Cabinet should also be lined with
suitable acoustic lining to dampen the machine noise and reverberations. The complete
package should be mounted on floor with anti-vibration mounting pads forming a part ofscope without extra price.
The units should be top / front at top discharge types.
Filters:
Filters should be manufactured from HDPE, of washable & easily removable type, with
filtration size of 20 microns and efficiency more than 85%. During installation, the filters
must be covered with plastic sheet to prevent clogging due to construction dust. During
commissioning, the filters must be covered with fine cloth for same purpose, to beremoved once the site is made free of dust. The plastic sheet and cloth shall be accounted
for while quoting and any separate price shall not be paid for same.
Compressors:
Compressors should be of hermetically sealed Scroll type of reputed make. Eachcompressor should have isolation valves, crankcase heater during off cycle, oil top-up
connection, gauge connections, (on compressor or built in valves), anti-vibration
mounting pads / fixtures and own terminal box. Capacity of the condenser should beadequate for the unit quoted, and the compressor should be capable of operating at the
conditions assumed for design for extended durations. Compressors selected must be
available readily in India at a notice of 48 hours. Compressors must be mounted onsuitable anti vibration mounting pads within the cabinet of the unit, and proper
provision must be made for compressor cooling as well as for accessibility of
maintenance / removal of compressor.
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Evaporator Coils:
The evaporator coils should be fabricated out of copper tubes and aluminium fins, with
circuitry designed to maintain required Apparatus Dew Point (ADP) at varying load
conditions. The coil circuitry should be designed for optimum performance as well as formaintaining a stable leaving air condition. Area of fins and tubes should be sufficient to
achieve required heat transfer, and the data must be furnished in the data sheet attached,
with offer. Coil must be provided with a drain pan manufactured out of 14 G StainlessSteel / other suitable material, duly insulated to avoid dripping of condensate outside the
cabinet. Proper arrangement for even distribution of refrigerant throughout the coil area,
proper oil return and for preventing liquid flood back to compressor must be made in thecoil design.
Evaporator Blower:
Centrifugal forward / backward curved blower should be of reputed make and relatedinformation must be furnished in the data sheet with the offer Material of construction for
blower can be Aluminium / G. I., based on manufacturers design. It should be capable ofdelivering required air flow at a static pressure arrived by adding the total pressure drop
occurring within the indoor unit in the evaporator coil, filters etc. to the external static
mentioned in the BOQ. It should be installed on sturdy mountings & should bedynamically balanced at operating speed. The blower motor should be capable of
operating at 20% excess flow and should also be capable of operating round the clock
with maximum flow (when filters are clean). Bearings and belts used in the blowerassembly must be available locally and the data must be furnished in the datasheet
attached.
Condenser:
Condenser section should be quoted with its own supports / stand / cowls if required
assuming floor/wall mounting and separate rate for such structural materials or standsshould not be quoted. Material of construction for tubes should be copper and that for fins
should be aluminium. Fan motors with weatherproof outdoor grade terminal box should
form a part of condenser. The motors should be capable of operating continuously inoutdoor exposure, with enclosure conforming to IP 55. The area of tubes and fins must be
designed suitably to achieve required heat discharge at design ambient and saturated
condensing temperatures. Data regarding same must be furnished in the datasheet. Thefins should be treated with anti corrosive coating to withstand salty and humid weather,
conforming to JIS Z 2371 or equivalent standard.
Panel:
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Control panel should have electrical switchgear and power /c control wiring required for
switching ON OFF evaporator and condenser fans, compressor, and Screen / LCD
displays for all motors ON, overload trips, fault trips with memory for minimum 5 faults,necessary interlockings and terminations.
Drawing showing electrical power and control circuitry, laminated by transparent Plasticsheets must be stored / adhered firms inside the unit panel.
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DATA TO BE FURNISHED WITH OFFER FOR PACKAGED A/C UNITS:
1. Make
2. Country of origin
3. Model
4. Capacity (at conditions mentioned in BOQ)5. Indoor unit :
i) Material of Constructionii) Thicknessiii) Surface treatmentiv) Width (mm)v) Depth (mm)vi) Height (mm)vii) Maintenance space required frontviii) Maintenance space required backix) Maintenance space required sides
6 No. of installations of same model in India7. No. of installations of same model in World wide
8. No. of trained service personnel in India
9. No. of trained service personnel in Kerala
10. Origin of spares country
11. Stock of spares nearest place
12. No. of circuits in each unit
13. No. of compressors in each circuit
14. Type of compressor Open/Semi-Hermetic/ Hermetically
sealed
15. Type of compression Reciprocating/ Scroll/ Screw
16. Make of compressor17. Model of compressor
18. Nominal capacity of compressor (compressor capacity chart
to be attached describing heat pumping capacity and power
consumption at various Saturated Suction temperatures and
Saturated condensing temperatures)
19. Nominal current drawn at 100% load
20. Maximum in rush current
21. Type of unloading
22. Capacity control steps
23. Condenser dimensions
i) width (mm)ii) depth (mm)iii) height (mm)
24. Condenser surface area (air side)
25. Condenser surface area (refrigerant side)
26 Condenser tube thickness
27 Condenser fin MOC
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28 Condenser fin spacing
29 Condenser fan cfm
30. No. of circuits
31. Type of capacity control for condenser, if provided ( fan
speed regulation )
32. Enclosure for condenser fan motors33. Type of evaporator
34. No. of circuits per evaporator
35. Type of capacity control
36. Make and model of blower
37. Evaporator blower quantity
38. Evaporator blower air flow (cfm)
39. Evaporator blower static gross (mm WG) (fan curves to beenclosed)
40. Evaporator surface area (air side)
41. Evaporator surface area (water side)
42 Evaporator tube thickness43 Evaporator Fin MOC
44 Evaporator fin spacing
45. Refrigerant name
46. Refrigerant charge
47. Oil name
48. Oil charge (Litres)
49. Type of air discharge (floor / top / side)
50. Size of air outlet
51. Size of air inlet
52. Type of filter
53. Filtration efficiency
54. Pressure drop across filter when choked
55 Type of panel Electrical/ Microprocessor/ PC Compatibility
with BMS?
56 Does panel require an interface to be connected with a PC?
57. Remote operation possible?
58. Controls provided for protection against
a) High voltage
b) Low voltage
c) Single phasing
d) Phase reversale) High/Low frequency
f) Damage to panel components due to momentarysurges/power cuts
g) High discharge pressure
h) Low suction pressure
i) Low oil circuit pressure
j) Low oil level
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k) Low refrigerant level
l) Motor overloads for compressor motors
m) Motor overloads for blower (evaporator) motors
n) Motor overloads for condenser fan
o) Filter choking
p) Scheduling possible?59. Temperature control level +/- C
60. Single line electrical power circuit diagram enclosed?
61. Control circuit diagram enclosed?
62. Description of control mechanisms enclosed?
63. List of fault displays enclosed?
64. Clear space required for supply air in front of condenser
65. Figures for cfm on evaporator & condenser side
66. Power consumption at operating conditions & 100% load
67. Compressor/s
68. Condenser fan/s
69. Noise level for indoor unit at 1 m.70. Noise level for outdoor unit at 3 m.
71. Confirm inclusion of canvass connections, indoor & outdoor
stands, anti vibration pads, plastic and cloth covering forfilters in the prices quoted yes / no
72. Confirm attaching capacity & power consumption charts for
compressor, fan curves yes / no
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WALL MOUNTED SPLIT A/C UNIT:
The units shall be used for cooling and dehumidifying air.
The units, with capacities as per Bill of Quantities, should be factory assembled and
tested prior to dispatch to site.
Units should be hi-wall type with indoor unit housing evaporator coil, blower, and
outdoor unit housing the condensers and fans.
Units should be carrying a BEE rating of minimum 3 stars.
Indoor Unit:
Indoor unit should be designed for mounting on a wall with the help of an in-built backmounting plate. It should comprise of plastic cabinet, evaporator coil & centrifugal fan
with drive.
Blower:
The blower should be designed for rated flow at a low noise level (below 45 Db) at full
speed. It should have settings for operating at three different speeds.
Grill:
A grill manufactured out of tough grade of plastic should cover the unit from lower side.
It should be provided with swinging type supply air louvers and fixed type return air
louvers. Central core should be removable with synthetic filters clipped on it.
Remote Control:
The unit should be fitted with a remote sensor having facility to receive signal from awireless remote to control ON/OFF, thermostat setting, fan speed and swing operations.
Outdoor Unit:
Outdoor unit should comprise of hermetically sealed compressor of capacity matching
with the evaporator. The compressor should be capable of continuous operation at anambient DBT of 45
0C.
Condenser:
Air cooled condenser having adequate heat rejection capacity and condenser fan with
motor should be housed within a weather proof sheet metal cabinet, along with
compressor.
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Sufficient louvers should be provided for air movement over condenser & fan motor. The
unit should have access panels to facilitate clearing & maintenance of internal
components.
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DATA TO BE SUBMITTED WITH OFFER:
(ITEM: HI-WALL SPLIT A/C UNIT)
1. Make
2. Model
3. Nominal capacity of unit TR
4. Capacity @ 35C Outdoor DBT & 24C IndoorDBT with 55% R.H.
TR
5. Power consumption at 35C outside DBT, 24C
inside DBT & 55% R.H. :
Compressors (total) KW
IDU fans (total) (at max. speed) KW
ODU fans (total) (at max. speed) KW
Total : KW
6. Compressor
7. Compressor model
8. Compressor make
10. Type of Compressor Recip./ Scroll/ Rotary12. Maximum ambient temperature at which machine
can operate continuously.C
13. ODU dimensions
L mm
W mm
H mm
14. IDU dimensions
L mm
W mm
H mm
15. ODU fan CFM (total)
16. ODU fan KW (total)
17. IDU fan CFM (total)
18. IDU fan KW (total)
20. Type of filters
21. Speed control available for IDU fan? Yes/ No
22. Noise level IDU at 1 m dB
23. Noise level ODU at 3 m dB
24. Permissible voltage range _______ volts +/- ___%
28. Nearest service station distance (km)
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AIR DISTRIBUTION
Scope:
The scope of this section comprises of supply, fabrication, installation, testing and
commissioning of all sheet metal/ aluminium ducts as specified in the Bill of Quantities,supply, installation, testing, commissioning and balancing of air flow across all grilles,
registers, diffusers and equipment, in accordance with these specifications and the
general arrangement shown on the Drawings.
Duct Materials:
All ducts shall be fabricated from galvanized steel sheets/ aluminium sheets of the
following thickness as indicated in Schedule of Quantities.
G. S. S. ALUMINIUM
Rectangular ducts up to 75 cm 24 Gauge 22 Gauge
Rectangular ducts from 76 to 150 cm and round ducts. 22 Gauge 20 Gauge
Rectangular ducts from 151 to 225 cm 20 Gauge 18 Gauge
Rectangular ducts greater than 225 cm 18 Gauge 16 Gauge
Sheet metal ducts shall be fabricated out of galvanized steel sheets. Fabrication of ductsshall be through Triplex lock former or multiple lock formers, conforming to relevant
BIS Codes. Sheets used shall be produced by Hot Dip Process and galvanizing shall be
Class V - Light Coating of zinc.
Samples of sheet from each lot selected at random by Owners site representative shall be
subject to approval & gotten tested for thickness and zinc coating at contractors
expenses. Zinc coating should be per IS:277.
All ducts shall be fabricated and installed in workmanlike manner, generally conforming
to relevant BIS Codes. Round exposed ducts shall be die-formed for achieving perfectcircle configuration.
a. Ducts so identified on the Drawings shall be acoustically lined with thermalinsulation as described in the section Insulation and as indicated in Schedule of
Quantities. Duct dimensions shown on Drawings are overall sheet metal dimensionsinclusive of the acoustic lining where required and indicated in Schedule ofQuantities.
b. Ducts shall be straight and smooth on the inside with neatly finished joints. All jointsshall be made airtight.
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c. All exposed ducts up to 60 cm width within conditioned spaces shall have slip joints -no flanged joints. The internal ends of slip joints shall be in the direction of airflow.
Ducts and accessories within ceiling spaces, visible from air-conditioned areas shallbe provided with two coats of mat black finish paint.
d.
Changes in dimensions and shape of ducts shall be gradual. Air-turns shall beinstalled in all vanes, arranged to permit the air to make the turn without appreciable
turbulence.
e. Ducts shall be fabricated as per details shown on Drawings. All ducts shall be rigidand shall be adequately supported and braced where required with standing seams,
tees, or angles, of ample size to keep the ducts true to shape and to prevent buckling,vibration or breathing.
f. All sheet metal connection, partitions and plenums required to confine the flow of airto and through the filters and fans shall be constructed of 18 gauge GSS/ 16 gauge
aluminium, thoroughly stiffened with 25 mm x 25 mm x 3 mm galvanized steel anglebraces and fitted with all necessary inspection doors as required, to give access to all
parts of the apparatus. Doors shall be not less than 45 cm x 45 cm in size.
g. Plenums shall be panel type and assembled at site. Fixing of galvanized angle flangeson duct pieces shall be with rivets heads inside i.e. towards G. S. sheet and rivetingshall be done from outside.
h. Rubber lining 4 mm thick shall be used between duct flanges instead of felt, in allducting installation.
i. All ducts shall be installed generally as per tender Drawings, and in strict accordancewith approved shop drawings to be prepared by the Contractor.
j. The Contractor shall provide and neatly erect all sheet metal work as may be requiredto carry out the intent of these Specifications and Drawings. The work shall meet withthe approval of Client / Consultant in all its parts and details.
k. All necessary allowances and provisions shall be made by the Contractor for beams,pipes, or other obstructions in the building, whether or not the same are shown on the
Drawings. Where necessary to avoid beams or other structural work, plumbing or
other pipes, and/ or conduits, the ducts shall be transformed, divided or curved to oneside, (the required area being maintained) all as per the site requirements.
l. If a duct cannot be run as shown on the Drawings, the Contractor shall install the ductbetween the required points by any path available, in accordance with other services
and as per approval of Clients Engineer.
m. All duct work shall be independently supported from building construction. Allhorizontal ducts shall be rigidly and securely supported, in an approved manner, with
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trapeze hangers formed of galvanized steel rods and galvanized steel angle/ channel
under ducts at no greater than 2 meter center. All vertical duct work shall be
supported by structural members at each floor. All duct supports shall be throughgalvanized steel insert plates left in slab at the time of slab casting. Galvanized steel
cleat with a hole for passing shall be welded to the plates. Trapeze hanger formed of
galvanized steel rods and angles/ channels shall be hung through these cleats.Wherever uses of metal insert plates are not feasible, duct support shall be through
rawl plugs by drilling holes in concrete slab and inserting rawl plug and bolts.
n. Ducting over furred ceiling shall be supported from the slab above, or from beams,after obtaining approval of Clients Engineer. In no case shall any duct be supported
from false ceiling hangers or be permitted to rest on false ceiling. All metal work indead or furred down spaces shall be erected in time to occasion no delay to other
Contractors work on the building.
o. Where metal ducts or sleeves terminate in woodwork, tight joints shall be made bymeans of closely fittings heavy flanged collars. Where ducts pass through brick ormasonry openings, wooden frame work shall be provided within the opening and
crossing ducts provided with heavy flanged collars on each side of wooden framework, so that duct crossing is made leak-proof.
p. All ducts shall be totally free from vibration under all conditions of operation.Whenever duct work is connected to fans, air handling units or fan coil units that may
cause vibration in the ducts, ducts shall be provided with one flexible connection shall
be constructed of fire retarding flexible heavy canvas sleeve at least 10 cm longsecurely bonded and bolted on both sides. Sleeve shall be made smooth and the
connecting duct work rigidly held by independent supports on both ends. The flexible
connection shall be suitable for pressure at the point of installation.
Dampers:
a. Dampers: All duct dampers should be of G.S.S.16G opposed blade & of robustconstruction and tight fitting. The design, method of handling and control shall be
suitable for the location and service required.
b. Dampers shall be provided with suitable links levers and quadrants as required fortheir proper operation. Control or setting devices shall be made robust, easily
operable and accessible through suitable access doors in the ducts. Every dampershall have an indicating device clearly showing the damper position at all times.
c. Dampers shall be placed in ducts at every branch supply or return air duct connection,whether or not indicated on the Drawings, for the proper volume control and
balancing of the system.
Supply & Return Air Registers:
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Supply & return air registers shall be of either steel or aluminium sections as specified in
schedule of quantities. Steel construction registers shall have primer Coat finish whereas
extruded aluminium registers shall be either anodized or Powder Coated as specified inSchedule of Quantities. These registers shall have individually adjustable louvers both
horizontal and vertical. Supply air registers shall be provided with key operated opposed
blade extruded aluminium volume control dampers anodized in matt black shade withstove enamel paint.
a. The registers shall be suitable for fixing arrangement have concealed or visiblescrews as approved by Architect. Linear continuous supply cum return air register
shall be extruded Aluminium construction with fixed horizontal bars at
0/15/30/45 inclination & flange on both sides. The thickness of the fixed barlouvers shall be minimum 5.5 mm in front and 3.8 mm in rear with rounded edges
and flange shall be 20 mm/ 30 mm wide as approved by Architect. The grills shall be
suitable for concealed fixing. Volume control dampers of extruded aluminium
anodized in black colour shall be provided in supply air duct collars. For fan coil units
horizontal fixed bar grills as described shall be provided with flanges on four sides &suitable for clip fixing.
b. All registers shall be selected in consultation with the Architect. Different spacesshall require horizontal or vertical face bars, and different width of margin frames.
These shall be procured only after obtaining written approval from Architect for each
type of register.c. All registers shall have a soft continuous rubber/ foam gasket between the periphery
of the register and the surface on which it has to be mounted. The effective area of the
registers shall not be less than 66% of gross face area.d. Registers shall be adjustable pattern as each grill bar shall be pivotable to provide
pattern with 0 to + 45 horizontal and deflection downwards. Bars shall hold
deflection settings under all conditions of velocity and pressure.e. Bar longer than 45 cm shall be reinforced by set-back vertical members of approved
thickness.
f. All volume control dampers shall be anodized in Mat black shade.Supply & Return Air Diffusers:
Supply & return air diffusers shall be as shown on the Drawings and indicated inSchedule of Quantities. Mild steel diffusers/ dampers shall be factory coated with rust-
resistant primer. Aluminium diffusers shall be powder coated & made from extruded
aluminium section as specified in schedule of quantities.
a. Rectangular Diffusers shall be steel/ extruded aluminium construction, square &rectangular, diffusers with flush fixed pattern for different spaces as per schedule ofquantities. These shall be selected in consultation with the Architect. These shall be
procured only after obtaining written approval from Architect for each type of
diffuser.
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b. Supply air diffusers shall be equipped with fixed air distribution grids, removablekey-smudge volume control dampers, and anti-smudge rings as required in specific
applications, and as per requirements of schedule of Quantities. The extrudedaluminium diffusers shall be provided with removable central core and concealed key
operation for volume control damper.
c. Linear Diffuser shall be extruded aluminium construction with removable core, oneor two-way blow type. Supply air diffusers shall be provided with volume control/
balancing dampers within the supply air collar. Diffusers for different spaces shall beselected in consultation with the Architect, and provided as per requirements of
schedule of Quantities. All diffusers shall have volume control dampers of extruded
aluminium construction anodized in mat black shade.
d. Linear Diffuser shall be extruded aluminium construction multi slot type with airpattern controller provided in each slot. Supply air diffusers shall be provided with
Hit & Miss volume control dampers in each slot of the supply air diffusers. Diffusers
for different spaces shall be selected in consultation with the Architect and providedas per requirements of Schedule of Quantities.
Measurements for Ducting:
Unless otherwise specified, measurements for ducting, for the project shall be on thebasis of centerline measurements described herewith.
a. Duct Work shall be measured on the basis of external surface area of ducts. Ductmeasurements shall be taken before application of the insulation. The external surface
area shall be calculated by measuring the perimeter comprising overall width and
depth, including the corner joints, in the center of each duct section, multiplying withthe overall length from flange face to flange face of each duct section and adding up
areas of all duct sections.
For tapered rectangular ducts, the average width and depth shall be considered forperimeter, whereas for tapered circular ducts, the diameter of the section midway
between large and small diameters shall be adopted, the length of tapered duct
section shall be the center line distance between the flanges of the duct section.
For special pieces like bends, tees, reducers, branches and collars, mode of
measurement shall be identical to that described above using the length along thecenter line.
The quoted unit rate for external surface of ducts shall include all wastageallowances, flanges and gaskets for joints, nuts and bolts, hangers and angles and
angle/ flat with double nuts for supports, felt strip between duct and support,
vibration isolator suspension where specified or required, inspection chamber/ accesspanel, splitter damper with quadrant and lever for position indication, turning vanes,
straightening vanes, and all other accessories required to complete the duct
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installation as per the Specifications. These accessories shall not be separately
measured nor paid for.
b. Special Items for Air Distribution shall be measured by the cross-section areaperpendicular to air flow, as identified herewith :
i. Grilles and registers - width multiplied by height, excluding flanges. Volumecontrol dampers shall form part of the unit rate for registers and shall not be
separately accounted.
ii. Diffusers - cross section area for airflow at discharge/ capture area, excludingflanges. Volume control dampers shall form part of unit rate for supply airdiffusers and shall not be separately accounted.
iii. Linear diffusers - shall be measured by linear measurements only, not by cross-sectional areas and shall exclude flanges for mounting of linear diffusers. The
supply air plenum for linear diffusers shall be measured with ducting asdescribed earlier.
iv. Fire dampers - shall be measured by their cross sectional area perpendicular tothe direction of airflow. Quoted rates shall include the necessary collars and
flanges for mounting, inspection pieces with access door, solenoid valves etc. Nospecial allowances shall be payable for extension of cross section outside the air
stream.
v. Flexible connection - shall be measured by their cross sectional areaperpendicular to the direction of airflow. Quoted rates shall include the necessary
mounting arrangement, flanges, nuts and bolts and treated-for-fire requisitelength of canvas cloth.
vi. Kitchen Hoods - shall be measured by their cross sectional area at the capturepoint of fumes, parallel to the surface of kitchen equipment. Quoted rates shallinclude the grease filters, provision for hood light, suspensions arrangement for
the hood, profile to direct the air to ventilation ducts and provision for removable
drip tray.
Testing and Balancing:
After the installation of the entire air distribution system is completed in all respects, all
ducts shall be tested for air leaks by visual inspection.
The entire air distribution system shall be balanced using an anemometer. Measured air
quantities at fan discharge and at various outlets shall be identical to or less than 5% inexcess of those specified and quoted. Branch duct adjustments shall be permanently
marked after air balancing is completed so that these can be restored to their correct
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position if disturbed at any time. Complete air balance report shall be submitted for
scrutiny and approval, and four copies of the approved balance report shall be provided
with completion documents.
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PIPING
Scope:
The scope of this section comprises the supply and laying of pipes, testing and balancing
of all drain water and refrigerant piping required for the complete installation. All pipinginclusive of fittings shall follow the applicable Indian Standards.
Pipe Sizes:
Pipe size shall be as required for the individual fluid flows, for providing smooth
noiseless balanced circulation of fluids.
Drain Piping:
a. All pipes to be used to condensate drain and fittings shall be galvanized steel class
B (medium class) conforming to relevant BIS Codes.
b. All jointing in the pipe system shall be by screwed/ welded joints and/ or byscrewed flanges using 3 mm 3 ply rubber insertion gaskets. Pipe threads and
flanges shall be as per relevant BIS Codes.
c. All pipe supports and nuts and bolts shall be milk steel, hot dip galvanized.
d. Fittings shall be galvanized steel medium class malleable casting of pressurerating suitable for the piping system. Sufficient number of flanges and unions
shall be provided for future cleaning and servicing of piping. Tee-off connection
shall be through equal or reducing tees.
e. All condensate drain piping shall be insulated and painted as per the sectionInsulation if indicated in Schedule of Quantities.
Refrigerant Piping:
a. All refrigerant pipes and fittings shall be soft/ hard drawn copper tubes and wroughtcopper/ brass fittings suitable for connection with silver solder/ Copper phos.
b. All joints in copper piping shall be sweet joints using low temperature brazing and/ orsilver solder. Before jointing any copper pipe or fittings, its interiors shall be
thoroughly cleaned using acetone. The piping shall be continuously kept clean of dirt
etc. while constructing the joints. Subsequently, it shall be thoroughly blown outusing carbon dioxide/ nitrogen.
c. Refrigerant lines shall be sized to limit pressure drop between evaporator andcondensing unit to less than 0.2 Kg per sq. cm.
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d. After the refrigerant piping installation has been completed, the refrigerant pipingsystem shall be pressure tested using Freon mixed with nitrogen/ carbon dioxide at a
pressure of 20 Kg per sq. cm (high side) and 10 Kg per sq. cm (low side). Pressureshall be maintained in the system for a minimum of 12 hours. The system shall then
be evacuated to a minimum vacuum of 70 cm of mercury and held for 24 hours,
during which period, change in vacuum shall not exceed 12 cm of mercury. Vacuumshall be checked with a vacuum gage.
e. All refrigerant piping shall be installed strictly as per the instructions andrecommendations of air conditioning equipment manufacturers.
Piping Installation:
a. Contractor must keep in view the specific openings in buildings and other structuresthrough which pipes are designed to pass.
b.
Piping shall be properly supported on, or suspended from, stands, clamps and hangersas specified and as required. The Contractor shall adequately design all the brackets,
saddles, anchors, clamps and hangers and be responsible for their structuralsufficiency.
c. Vertical risers shall be parallel to walls and column lines and shall be straight andplumb. Risers passing from floor to floor shall be supported at each floor slab by
clamps or collars attached to pipe and with a 15 mm thick rubber pad or any resilient
material. Where pipes pass through the terrace floor, suitable flashing shall beprovided to prevent water leakage. Risers shall have a suitable clean out at the lower
point and air vent at the highest point.
d. All piping work shall be carried out in workmen like manner, causing minimumdisturbance to the existing services, buildings, roads and structure. The entire piping
work shall be organized, in consultation with other agencies work, so that laying of
pipe supports, pipes and pressure testing for each area shall be carried out in onestretch.
e. Cutouts in the floor slabs for installing the various pipes are indicated in theDrawings. Contractor shall carefully examine the cutouts provided and clearly point
out where the cutouts shown in the Drawings do not meet with the requirements.
Measurement for Piping:
Measurement for piping for the project shall be on the basis of center line measurements
described herewith.
Refrigerant piping for all a/c units shall be measured as one way, one circuit per unit.
That is, even if a typical 11 TR machine is having 2 circuits and 2 sets of suction and
liquid pipes, the piping should be measured as only one pipe, thus the rate should be
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quoted assuming 2 running meters of suction pipe and 2 running meters of liquid pipe, if
B.O.Q. mentions quantity of 1 running meter.
Same measurement procedure shall apply for cabling between units.
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INSULATION
Scope:
The scope of this section comprises the supply and application of insulation conforming
to these specifications.
Material:
Insulation material shall be Resin bonded Glass wool lined with Aluminium Foil /
Elastomeric Nitrile Rubber / Cross linked expanded Polyethylene / Expanded Polystyrene
/ Expanded Polyurathene Foam as specified in BOQ, and of density and thickness asspecified in BOQ.
Thickness of the insulation shall be as specified for the individual application. Each lot of
insulation material delivered at site shall be accompanied with manufacturer test
certificate for thermal conductivity values and density. Samples of insulation materialfrom each lot delivered at site shall be selected at random for approval and shall be tested
for thermal conductivity values and density at contractors cost by Construction Manager.Adhesive used for setting the insulation shall be non-flammable, vapour proof adhesive,
Shalimar CPRX compound, or approved equal, cold setting compound.
Duct Lining:
Ducts so identified and marked on Drawings and in Schedule of Quantities shall beprovided with acoustic lining of thermal insulation material as follows:
The inside surface for the ducts shall be covered with adhesive, and provided withwooden battens 25 mm wide, 25 or 50 mm thick, treated with selenium and fire resistant
paint, screwed on the inside of duct, spaced not more than 60 cm centers. The gaps
between wooden battens shall be filled with 25 to 50 mm thick, about 60 x 60 cm wide
cut panels of Resin bonded Glass fiber of density 40 Kg/ Cubic m.
These insulation slabs shall be fixed to the sheet metal with cold setting adhesive
compound. The inside surface shall be covered with RP tissue paper and 26 gaugeperforated aluminium sheet having at least 15% perforation. The aluminium sheet shall
be screwed to wooden battens using cup washer and neatly finished to give true inside
surfaces. Use of nails for nailing shall not be permitted.
Duct Insulation:
External thermal insulation on ducts shall be provided as follows:
Duct surfaces should be cleaned. 25/50 mm thick Glass wool roll of density specified intender BOQ, lined with Aluminium foil should be wrapped over all sides of duct with the
help of bituminous adhesives in a manner to leave no air gaps between the duct surface &
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insulation. Metal clips and / or metallic straps should be used for this purpose wherever
necessary. The joints should be then sealed with minimum 50 mm thick aluminium self -
adhesive tape.
Duct Attenuators:
Attenuators shall be installed in ducts in accordance with requirements of drawings and
as included in Schedule of Quantities.
a. Attenuators shall be of steel construction with casings out of minimum 22 Ggalvanized steel. Acoustic fill shall be inert, non-hygroscopic, vermin proof, fiber
glass of required density adequately protected against corrosion and covered with 26G perforated aluminium sheets. Attenuators shall be supplied complete with flanges.
b. Acoustic performance of the attenuators (net insertion loss) shall meet or exceed thevalues listed below :
OCTAVE BAND CENTRE FREQUENCY Hz
63 125 250 500 1K 2K 4K 8K
Insertion loss dB 900 mm long
attenuators
2 7 12 19 23 23 18 11
Insertion loss dB 1500 mm longattenuators
6 10 18 30 42 34 23 14
c. The pressure drop values of the silencers shall be indicated for each duty.d. Manufacturers shall submit a test certificate for acoustic and aerodynamic
performance of the attenuators. Attenuators shall be tested in accordance with ACMAtest methods/ BS 4718 and insertion loss and self generated noise for each octave
band and pressure drop shall be stated in the schedule.
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Measurement of Insulation:
Measurement for duct and pipe insulation for the project shall be on the basis of centerline measurements described herewith:
Pipe Insulation: shall be measured in units of length along the center line of the installedpipe, strictly on the same basis as the piping measurements described earlier. The linearmeasurements shall be taken before the application of the insulation. It may be noted that
for piping measurement, all valves and orifice plates and strainers are separately
measurable by their number and size. It is to be clearly understood that for the insulationmeasurements, all these accessories including cladding, valves, orifice plates and
strainers shall be considered strictly by linear measurements along the center line of pipes
and no special rate shall be applicable for insulation of any accessories, fixtures orfittings whatsoever.
Duct Insulation & Acoustic Lining: shall be measured on the basis of surface area along
the center line of insulation thickness. Thus the surface area of externally thermallyinsulated or acoustically lined duct shall be based on the perimeter comprising center line
(of thickness of insulation) width and depth of the cross section of insulated or lined duct,multiplied by the center-line length including tapered pieces, bends, tees, branches, etc.
as measured for bare ducting.
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VENTILATION FANS
CAPACITY: AS PER SCHEDULE ENCLOSED.
Fans should be of make as per list of makes approved, of centrifugal forward/ backward
curved DIDW / SISW type, or of axial flow type, as mentioned in Bill of Quantities.
The fans should be provided with required drive set (direct / pulley & belt). Necessary
guards and alignment/ tightening facilities should be provided.
Base frame foundation bolts and vibration isolation pads should form a part of supply
package. Inlet & outlet flexible connections with fasteners should also form a part ofsupply package.
The fans should be statically & dynamically balanced at operating speed & certification
of that effect must be produced with supply.
The entire assembly should be accessible for maintenance.
The fan should be selected to operate at a speed within the most efficient operating range
of the pressure flow curve.
Charts/ curves must be submitted along with the technical specifications.
Motor should be selected to withstand a flow with at least 20% more than designparameters, and / or 20% less static.
Efficiency of fans at operating conditions should be more than 70%.
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DATA TO BE SUBMITTED WITH OFFER :
VENTILATION FANS
1. Make
2. Model / Type
3. Casing :
a) M.O.C.
b) Treatment
c) Thickness
4. Fan :
a) Make
b) Model
c) Size
i) Width
ii) Diameter
d) Qty.
e) Blades typef) Speed
g) Flow
h) Static
i) Power consumed at operating conditions
j) Power consumed at 20% excess flow
k) Performance curves
l) Type of lubrication
m) Drive arrangement
n) Blades MOC
o) Whether statically & dynamically balanced
p) Type of bearings
q) Efficiency at design conditions
5. Motor :
a) Make
b) Type
c) RPM
d) Rating
e) Enclosure
f) Insulation
g) Full load current
h) No load currenti) Frame size
j) Efficiency at operating conditions
k) Power consumption at operating conditions
l) Performance curves
6. Overall :
a) Operating weight
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b) Noise level at 3 m
7. Base frame/ base plate included Yes / No
8. Foundation bolts included Yes / No
9. Anti-vibration pads included Yes / No
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ELECTRICAL PANELS
Scope:
The scope of this section comprises of fabrication, supply, erection, testing and
commissioning of electric control panels.
Work should be carried out in accordance with the Specifications, Local Rules, Indian
Electricity Act 1910 as amended up to date, and rules issued there under, Regulations ofthe Fire Insurance Company and relevant BIS Codes of Practice. The control panels
should be BIS approved and manufactured by a reputed manufacturer and should be IP
52/ IP 54.
The panels should be manufactured by a manufacturer having certification of
manufacturing panels for 50 KVA short circuit current rating from C.P.R.I.
Construction Features:
The Control panel should be sheet steel cabinet for indoor installation, dead front, floormounting/ wall mounting type. The control panel should be totally enclosed, completely
dust and vermin proof and should be with hinged doors, Neoprene gasket and padlocking
arrangement. Steel sheets used in the construction of panel should be 2 mm thick andshould be folded and braced as necessary to provide a rigid support for all components.
Joints of any kind in sheet metal should be seam welded, all welding slag should be
grounded off and welding pits wiped smooth with plumber metal.
All panels and covers should be properly fitted and square with the frame, and holes in
the panel correctly positioned. Fixing screws should enter into holes tapped into anadequate thickness of metal or provided with wing nuts. Self-threading screws should not
be used in the construction of Control panels. A base channel of 75 mm x 75 mm x 5 mm
thick should be provided at the bottom for floor mounted panels. Minimum clearance of
200 mm should be provided between the floor of Control panel and the lowest unit.
The control panel should be of adequate size with a provision of 25% spare space to
accommodate possible future switchgear. Switches should be arranged in multi-tier.Knockout holes of appropriate size and number should be provided in the Control Panel
in conformity with the location of cable/conduit connections. Removable sheet steel
plates should be provided at the top to drill holes for cable entry at site if required.
Every cabinet should be provided with Trafolyte or engraved metal nameplates. All
panels should be provided with circuit diagram engraved on PVC sheet. All liveaccessible connections should be shrouded and minimum clearance between phase and
earth should be 20 mm and phase to phase should be 25 mm.
All equipment such as meters and indicating lamps etc. should be located adjacent to the
unit with which it is associated and care should be taken to achieve a neat and
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symmetrical arrangement. Facility should be provided for termination of cables from both
above and below the control panel. Where cables enter from below, cable boxes should
be fitted at the rear and arranged in tiers to facilitate making connections to the upper andlower units. Clamps should be provided to support the weight of the cables. All power
wiring inside the control panel should be colour coded and control wiring ferruled for
easy identification.
Wiring System:
All L T power cabling between MCC and motors should be carried out with 415 volts
grade PVC insulated, overall PVC sheathed aluminium conductor armoured cables.
Cables should be sized by applying proper derating factor. All control wiring should becarried out by using 1100 volts PVC insulated copper conductor wires in raceways or in
conduit. Minimum size of control wiring should be 1.5 sq.mm PVC insulated copper
conductor wires. Minimum size of conductor for power wiring should be 4 sq.mm 415
volts grade PVC insulated copper conductor wires in conduit.
Circuit Compartment:
Each circuit breaker, contactor and relay should be housed in a separate compartment and
should have steel sheets on top and bottom of compartment. Sheet steel hinged locable
door should be duly interlocked with the breaker in the ON position. Safety interlocksshould be provided to prevent the breaker from being drawn out when the breaker is in
ON position. The door should not form an intergral part of the draw out portion of the
panel. Sheet steel barriers should be provided between the tiers in a vertical section.
Instrument Accommodation:
Adequate space should be provided for accommodating instruments, indicating lamps,
control contactors and control fuses etc. These should be accessible for testing and
maintainance without any danger of accidental contact with live parts of the circuit
breaker and bus bar. ON lamps should be provided on all outgoing feeders.
Bus Bars and Bus Bar Connections:
The bus bar and interconnections should be of aluminium and of rectangular cross section
suitable for full load current for phase bus bars and 50% for neutral bus bar and should be
extendable on either side. The bus bars and interconnections should be insulated withheat shrinkable sleeve and should be colour coded. The bus bars should be supported on
glass fibre reinforced thermosetting plastic insulated supports at regular intervals to
withstand the force arising from in case of short circuit in the system. All bus bars shouldbe provided in a separate chamber and should be shrouded throughout, all connections
should be done by bolting and additional cross section area to be provided to compensate
for the holes drilled in the bus bars. All connections between bus bars and breakersshould be through solid strips of proper size to carry full rated current and insulated with
insulating tapes.
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Cable Compartments:
Cable compartment of adequate size should be provided in the control panels for all
incoming and outgoing cables entering from bottom or top. Adequate and proper supports
should be provided in cable compartments to support cables.
Labels:
Aluminium Anodised labels should be provided on all incoming and outgoing feeder
switches. Circuit diagram showing the arrangements of the circuit inside the Control
Panel should be pasted on inside of the panel door and covered with transparent plasticsheet. Cable alley and bus chamber should be identified on all panels.
Rubber Mat:
Rubber mat should be provided to cover the full length of front of all panels and rear ofpanels where back space should be available for working from the rear.
Materials:
All materials should be of the best quality complying with the BIS (Bereau of IndianStandards) specifications. Materials used should be subject to the approval of the Client
and samples of the same should be furnished where required.
a. Air Circuit Breakers: The Air Circuit Breakers should be sheet metal enclosed flushfront, draw out type, and should be provided with a trip free manual operating
mechanism with mechanical ON -- OFF indications. The circuit breaker shouldbe suitable for continuous rating and of capacity as called for. It should be possible to
switch ON and OFF the Circuit Breaker without opening the circuit breaker
compartment door. The operating handle and the mechanical trip push button should
be at the front of the breaker and integral with the breaker.
Cradle: The cradle should be so designed and constructed as to permit smooth
withdrawl and insertion of the breaker into it. The movement should be free fromjerks, easily operable and should be on steel balls/ rollers and not on flat surfaces.
Protective Devices: C. T. operated IDMT Relays for short circuit and earth faultoperation should be provided for all air circuit breakers.
Suitable under voltage tripping mechanism for voltage less than + 10% of full ratevoltage should be provided.
b. Selector Switch: Where called for, selector switches of rated capacity should beprovided in control panels, to give the choice of operating equipment in selective
mode.
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c. Moulded Case Circuit Breakers: Moulded Case circuit Breaker should be of motorduty and should be suitable for continuous load, manufactured in accordance withrelevant BIS Codes.
d.
Starters: Each motor should be provided with a starter of suitable rating. Startersshould be in accordance with relevant BIS Codes. All Star Delta and ATS Starters
should be fully automatic.
Starter contactors should have 3 main and 2 Nos. NO/ NC auxiliary contacts and
should be air break type suitable for making and breaking contact at minimum power
factor of 0.35. For design consideration of contactors the starting current of connectedmotor should be assumed to be 6 times the full load current of the motor in case of
direct-on-line starters and 3 times the full load current of the motor in case of Star
Delta/ Reduced Voltage Starters. The insulation for contactor coils should be of Class
E.
Operating coils of contactors should be suitable for 220/ 415 + 10% volts AC, 50
cycles supply system. The contactors should cut out when voltage drops to 90% ofthe rated voltage. The housing of the contactors should be heat resistant and having
hinge impact strength. Each starter should have thermal overload protection on all
three phases.
e. Over Load Relays: Contactors should be provided with a three element, positiveacting ambient temperature compensated time lagged thermal over load relays withadjustable setting. Relays should be directly connected for motors upto 35 HP
capacity. C. T. operated relays should be provided for motors above 35 HP capacity
Heater circuit contactors may not be provided with over load relays.
f. Current Transformers: Current transformers should be of accuracy class I and suitableVA burden for operation of the connected meters and relays. These should be resin
bounded and epoxy coated.
g. Single Phase Preventer: Single phase preventers should be provided only incasesingle phasing prevention feature is not built in the over load. Single Phase preventersshould be in conformity with relevant BIS standards. Single phase preventers should
act when the supply voltage drops down to 90% of the rated voltage or on failure of
one or more phases.
h. Time Delay Relays: Time delay relays should be adjustable type with time delayadjustable from 0-180 seconds and should have one set of auxilliary contacts forindicating lamp connections.
i. Indicating Lamp & Materials: All meters and indicating lamps should be inaccordance with BS 37 and BS 39. The meters should be flush mounted type. The
indicating lamp should be of low wattage. Each main panel should be provided with
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voltmeter 0-500 volts with three way and off selector switch, CT operated ammeter of
suitable range with three nos. CTs of suitable ratio with three way and off selector
switch, phase indicating lamps, and other indicating lamps as called for. Each phaseindicating lamp should be backed up with 5 amps fuse. Other indicating lamps should
be backed up with fuses as called for.
j. Toggle Switch: Toggle switches, where called for, should be in conformity withrelevant BIS Codes and should be of 5 amps rating.
k. Push Button Stations: Push button stations should be provided for manual starting andstopping of motors/ equipment as called for Green and Red colour push buttons
should be provided for Starting and Stopping operations. Start or Stopindicating flaps should be provided for push buttons. Push buttons should be suitable
for panel mounting and accessible from front without opening door, Lock lever
should be provided for Stop push buttons. The push button contacts should be
suitable for 6 amps current capacity.
l. Conduits: Conduits should be of mild steel and should be Hard drawn, stoveenameled inside and outside with minimum wall thickness of 1.6 mm for conduitsupto 32 mm diameter and 2 mm wall thickness for conduits above 32 mm diameter.
GI pull wires should be installed in the conduit while laying the conduit.
m. Cables: M. V. Cables should be PVC insulated aluminium conductor and armouredcables conforming to BIS Codes. Cables should be armoured and suitable for laying
in trenches, duct, and on cable trays as required. M. V. Cables should be termiteresistant. Control cables and indicating panel cables should be multi core PVC
insulated copper conductor and armoured cables.
n. Wires: 415 volts grade PVC insulated copper conductor wires in conduit should beused.
Cable Laying:
Cable should be laid generally in accordance with BIS Code of Practice. Cables should
be laid on 14 gauge perforated MS sheet cable trays, and cable drops/ risers should befixed to ladder type cable trays fabricated out of steel angle. Access to all cables should
be provided to allow cable withdrawl/ replacement in the future. Where more than one
cable is running, one dia spacing should be provided to minimize the loss in currentcarrying capacity. Cables should be suitably supported with Galvanized saddles when run
on walls/ trays. When buried, they should be laid in 350 mm wide and 750 mm deep
trench and should be covered with 250 mm thick layer of soft sifted sand & protectedwith bricks, tiles. Special care should be taken to ensure that the cables are not damaged
at bends. The radius of bend of the cables when installed should not be less than 12 times
the diameter of cable. 1.1 KV cable should be buried 600 mm below ground level.
Wire Sizes:
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For all single phase/ 3 phase wiring, 415 volts grade PVC insulated copper conductor
wires should be used. The equipment inside plant room and AHU room should beconnected to the control panel by means of insulated copper conductor wires of adequate
size in exposed conduits. Final connections to the equipment should be through wiring
enclosed in galvanized flexible conduits rigidly clamped at both ends. An isolator shouldbe provided near each motor/ equipment wherever the motor/ equipment is separated
from the supply panel through a partition barrier or through ceiling construction. PVC
insulated single standard copper conductor wires should be used inside the control panelfor connecting different components and all the wires inside the control panel should be
neatly dressed and plastic beads should be provided at both the ends for easy
identification in control wiring.
The minimum size of control wiring should be 1.5 sq.mm PVC insulated standard soft
drawn copper conductor wires drawn through conduit to be provided for connecting
equipment and control panels.
All the switches, contactors, push button stations, indicating lamps should be distinctly
marked with a small description of the service installed. The following capacitycontactors and overload relays should be provided for different capacity motors or as per
manufacturers recommendation.
MOTORS TYPE OFSTARTER
CONTACTORCURRENT CAP.
OVERLOADRELAY RANGE
5 HP Motors D.O.L. 16 Amps 6 - 40 Amps
7.5 HP Motors D.O.L. 16 Amps 9 - 15 Amps
10 HP Motors Star Delta 32 Amps 9 - 15 Amps
12.5 HP Motors Star Delta 16 Amps 9 - 15 Amps15 HP Motors Star Delta 25 Amps 9 - 15 Amps
20 HP Motors Star Delta 32 Amps 14 - 23 Amps
25 HP Motors Star Delta 32 Amps 14 - 23 Amps
30 HP Motors Star Delta 40 Amps 20 - 33 Amps
35 HP Motors Star Delta 40 Amps 20 - 33 Amps
40 HP Motors Star Delta 40 Amps 30 - 50 Amps
45 HP Motors Star Delta 63 Amps 30 - 50 Amps
50 HP Motors Automatic Star
Delta
63 Amps 30 - 50 Amps
60 HP Motors - do - 125 Amps 30 - 50 Amps
75 HP Motors - do - 125 Amps 90 - 150 Amps
100 HP Motors - do - 200 Amps CT operated Relay
135 HP Motors - do - 300 Amps - do -
150 HP Motors Auto Transformer 300 Amps - do -
200 HP Motors - do - 300 Amps - do -
250 HP Motors - do - 400 Amps - do -
300 HP Motors - do - 400 Amps - do -
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400 HP Motors - do - 600 Amps - do -
600 HP Motors - do - 900 Amps - do -
Earthing:
Earthing should be provided as per IS:3043-1987 and should be copper strips/ wires. Themain panel should be connected to main earthing system of the power supply. All singlephase metal clad switches and control panels be earthed with minimum 3 mm diameter
copper conductor wire. All 3 phase motors and equipment should be earthed with 2
numbers distinct and independent insulated copper wires/ tapes as follows :
i) Motors upto & including 10 HP rating. 2 Nos. 3 mm dia copper wires.
ii) Motors 12.5 HP to 40 HP capacity. 2 Nos. 4 mm dia copper wires.
iii) Motors 50 HP to 75 HP capacity. 2 Nos. 6 mm dia copper wires.
iv) Motors above 75 HP. 2 Nos. 25 mm x 3 mm copper strips.
All switches should be earthed with two numbers distinct and independent copper wires
tapes as follows:
i. 3 phase switches & control panelsupto 60 amps rating.
2 Nos. 3 mm dia copper wires.
ii. 3 phase switches & control panelsupto 63 amps to 100 amps rating.
2 Nos. 4 mm dia copper wires.
iii. 3 phase switches & control panels 125amps to 200 amps rating.
2 Nos. 6 mm dia copper wires.
iv. 3 phase switches, control panels, bus
ducts, above 200 amps rating.
2 Nos. 25 mm x 3 mm Copper tapes.
The earthing connections should be tapped off from the main earthing of electrical
installation. The overlapping in earthing strips at joints should be riveted with brass rivets& brazed in approved manner. Lugs of adequate capacity and size should be used for all
termination of wires. Lugs should be bolted to the equipment body to be earthed after the
metal body is cleaned of paint and other only substance, and properly tinned.
Drawings:
Shop drawings for control panels and wiring of equipment showing the route of conduitcable should be submitted by the contractor for approval of Client & Consultant before
starting the fabrication of panel and starting the work. On completion, four sets of
complete As-installed drawings incorporating all details like, conduits routes, numberof wires in conduit, location of panels, switches, junction/ pull boxes and cables route etc.
should be furnished by the Contractor.
Testing:
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Before commissioning of the equipment, the entire electrical installation should be tested
in accordance with relevant BIS codes and test report furnished by a qualified and
authorised person. The entire electrical installation should be got approved by ElectricalInspector and a certificate from Electrical Inspector should be submitted. All tests should
be carried out in the presence of the Clients engineers.
Painting:
All sheet steel work should undergo a process of degreasing, through cleaning, andpainting with a high corrosion resistant primer. All panels should then be baked in an
oven. The finishing treatment should be by application of synthetic enamel paint of
approved shade.
Measurement of Electrical Control Panels:
Panels should be counted as number of units. Quoted rates should include as lumpsum(NOT measurable lengths) for all internal wiring, power wiring and earthing connections
from the control panel to the starter and to the motor, control wiring for interlocking,
power and control wiring for remote start/ stop as well as indication as per the
specifications. The quoted rate of panel should also include all accessories, switchgear,fuses, contactors, indicating meters and lights as per the specifications.
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ELECTRICAL DISTRIBUTION PANEL FOR A/C PLANT (EXTENSION SIDE)
QTY.: 1 No.
INCOMER: Main Incomer Isolator - MCCB 630 Amps., with protection against earth
fault / phase reversal / single phasing / low / high voltage / phase imbalance.Voltmeter
Ammeter
Voltmeter Selector SwitchAmmeter Selector Switch
CTs
Busbars for incomerBusbars for outgoing
R-Y-B indicating Lamps
Test push button to test all lamps
OUTGOING:Sections1 to 11 (each to have):
MCCB 63 Amps., with earth fault protection.Terminals for outgoing & earthing
ELECTRICAL DISTRIBUTION PANEL FOR A/C PLANT (MAIN SEATINGSIDE)
QTY.: 1 No.
INCOMER: Main Incomer Isolator - MCCB 630 Amps., with protection against earth
fault / phase reversal / single phasing / low / high voltage / phase imbalance.VoltmeterAmmeter
Voltmeter Selector Switch
Ammeter Selector SwitchCTs
Busbars for incomer
Busbars for outgoingR-Y-B indicating Lamps
Test push button to test all lamps
OUTGOING:Sections1 to 9 (each to have):
MCCB 63 Amps., with earth fault protection.
Terminals for outgoing & earthing
SPECIAL CONDITIONS FOR HVAC WORK
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1.0 TECHNICAL DOCUMENTATION WITH OFFER:
In order to have a fair comparison among all quotes, and to ensure an installationconforming to the specifications, the tenderers must submit all technical
information asked for in the technical specifications / BOQ in the prescribed
format. The offer shall be considered invalid in absence of the data sheets, orshort or wrong information being provided.
Similarly, the first step after issue of GFC drawings to the successful bidder shallbe submission of shop drawings, technical submittals for all equipment and
submission of a block bar chart by the bidder. The contractor is supposed to
prepare above, after detailed survey of site and GFC drawings. Any work carriedout in absence of approved shop drawings shall not be considered for
measurement.
2.0 PRINTED TERMS:
Tenderers standard printed/ cyclostyled terms and conditions will not be
acceptable. If the Contractors are departing from any of the tender specificationsor terms and conditions, they should specifically bring this out in their quotation.
Technical data of all equipment must be furnished as per formats provided.
3.0 QUANTITIES:
The Probable Quantities of the several items of work furnished are for thetenderer, convenience. The schedule of Probable Quantities is liable to alteration
by omission, deletion or addition at the discretion of the Client/ Consultant at the
time of execution of work. The Contract is on item rate basis.
The rates must be kept valid for ordering up to the completion and handing over
of the project.
4.0 DEVIATIONS FROM TENDER SPECIFICATIONS / CONDITIONS:
In order to install an effective system, the tenderers may quote with deviations.However, tenderers must quote for tender BOQ and quote separately for
deviations, if any. On scrutiny of such deviated quotes, the client may or may not
consider the deviation for comparison.
5.0 COORDINATION:
The contractor will coordinate with the related agencies, including but not limited
to the following during all stages of contract and maintenance period.
Project Management Team of Client. Architects & Consultants.
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Related other Contractors. Agencies of various inter related services. Local, State & Central Govt. bodies.
6.0 POWER & WATER:
Client shall provide power & water to contractor at one point in the building on
chargeable basis. The contractor shall follow all the statutory requirements ofsafety and electrical Inspectorate for installing own DG sets, without any
obligations of Client.
7.0 STORAGE SPACE:
Client shall provide open space to the contractor for storage of materials etc. Thequantity of space required must be notified to the client along with the Bar Chart.
The contractor shall arrange for hutment/ roofing/ storage racks/ any other
facilities required at his cost. The bidder, on receiving the space, shall use theplace/s in a proper manner, without causing damage to the property/ people
working in the premises. The materials/ tools shall be stored in a proper manner
as recommended by standard / manufacturer recommended practices and should
be open for inspection to the Client/Consultant. The responsibility of well beingof the materials up to handing ever stage shall be on the Bidder/ Contractor/
Manufacturer/ Supplier.
8.0 SHARING OF WORKPLACE:
Due to the fact that all agencies like civil, electrical, plumbing, carpentry, false
ceiling etc., shall be working together at site, the contractor shall work in co-ordination with other agencies and workplace should be shared. The bar chart
should be superimposed over bar chart of other agencies and sufficient floatsshould be provided for each activity.
9.0 DEMOBILISATION:
The Contractor shall within a week after the completion of the work clear from
the site his labour, material and machinery and hand over the premises to the
Client in neat and clean condition. If he fails to do so within the said period, theOwners have the right to get the same done through agencies and recover the cost
from the Contractor.
10.0 ERECTION TOOLS:
The successful bidder shall have to arrange for all necessary tools & tackles,
consumables, lights & lighting fixtures, scaffoldings, temporary structures, lifting
tools, cranes, chain pulley blocks, ropes hoists, erection consumables, cables etc.
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at their cost & resources. The client shall offer only open space and electricity at
one point in the premises. Electricity shall be chargeable at prevailing rate
decided by Client which shall be informed to the bidder before starting the work.
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11.0 SUB-CONTRACTORS:
Appointment of the Sub-Contractor, if any, shall be made after getting writtenconsent from the Consultants/ Client.
12.0 COMPLETION PERIOD:
The time or times for completion shall be as per signed document and shall
include Govt., Public and religious holidays, bad weather and storms etc. TheContractor shall not be entitled to request for extensions of time or any rights,
indemnities or damages due to these factors.
The Contractor shall not be deemed to have completed its obligations unless a
signed Completion Certificate has been issued by Client.
13.0 PROGRESS CHART/ BAR CHART:
The Contractor shall prepare a Bar Chart (MS project-98) indicatingcompletion time as per Contract and submit the same for approval toArchitects within 15 days from the date of letter of intent. The said Bar Chart
on approval from Architects & Consultant shall be a part of Contract
document.
The approved Bar Chart shall have not less than 5 nos. of summary taskcovering a specific area or floor, which is mostly independent of other
summary tasks. Each summary task shall be considered as independentproject. The Bar Chart shall be in a form approved by the Architect and
consultant.
The Bar Chart shall indicate manpower employed for each activity and thenumber of skilled and unskilled manpower proposed to be employed in each
week for each activity, based on productivity, to comply with completion
time.
The chart shall indicate scheduling of samples, shop drawings, approval,delivery of material, Inspection/ testing and commissioning of the systems.
The Contractor shall submit weekly reports (in triplicate), activity wise andclearly indicate the variation from the original chart and indicate action takento comply with the contract.
14.0 RATE OF PROGRESS:
If for any reason, which does not entitle the Contractor to an extension of time,the rate of progress of the Works or any section is at any time, in the opinion, of
Consultants, too slow to comply with the time of completion, Client shall notify
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the Contractor who shall there upon shall take such steps as are necessary, subject
to approv