Military Engineer Services Tender

A. COMPRESSORS: Floor-mounted compact screw-type chiller machine complete with semi-hermatic twin screw type compressors with independent circuits, water-cooled S/T type condenser, S/T horizontal flooded type evaporator with carbon steel shell and seamless copper tubes with 19 mm nitrile rubber insulation, common base frame, interconnected copper refrigerant piping and wiring, vibration isolators, gauge panel, automatic safety controls, flow switch at evaporator and condenser and ozone friendly CFC-free refrigerant gas R-22/R-407C / R410a. The refrigerant flow control shall use an electronic expansion valve. The chiller shall be designed for a working pressure of 150 psig and hydraulically tested at 225 psig. A number of properly spaced baffles shall be provided for maintaining optimum water velocity and heat transfer and the tubes shall be adequately supported.

B. CHILLERS: Chillers shall be factory AHRI tested at design conditions at 100%, 75%, 50% and 25% load respectively. Test certificates shall be produced for all three chillers. The chiller shall be BMS compatible and shall have RS485 / RS232 serial communication protocol. The motor shall be suitable for 3-Phase, 415 Volts ± 10%, 50 Hz, AC electric supply. Electric panel shall have an IP 54 rating, as per specification and drawings. The chiller shall be as per the approved particular technical specifications and shall meet the following design criteria: (a) Chiller: (i) Chilled Water IN: 54° F, (ii) Chilled Water OUT: 44° F (iii) Fouling Factor: 0.0005 (in FPS units) (iv) Water Flow Rate: 2.67 USgpm/TR

(b) Condenser: (i) Condenser Water IN: 90° F (ii) Condenser Water OUT: 100° F (iii) Fouling Factor: 0.001 (in FPS units) (iv) Water Flow Rate: 4.25 USgpm/TR (c) Minimum COP (at ARI conditions): 4.15 (d) Condenser Section: Shell and Tube type condenser internally knurled copper tubes. (e) Expansion Valve: Electronic expansion valve should be capable enough to operate on wider temperature range with energy efficient improvement at part load conditions as per manufacturer’s specifications (f) Evaporator: Flooded type evaporator all as per manufacturer’s specifications.

(g) Safety Protection: Safety protection on low cooling temperature, low oil pressure, high refrigerant pressure, electric leak, compressor overload, high/low voltage and single phasing shall be provided. Automatic control of refrigerant condition and compressor ON/OFF status and loading sequence system shall be provided. (h) Refrigerant: HFC-134 A/HFC-410 A/ HFC-407 C of zero ozone depletion potential refrigeration circuits of total capacity as per manufacturers specifications. (j) Control: Micro Processor control with LCD interface capable of monitoring all machine operating parameters like suction/discharge pressure, oil pressure, compressor operating hours, set point, air temperature, entering / leaving water temperature etc complete and precisely manages the operation of compressors, expansion devices, fans and of the evaporator/chiller water pump for optimum energy efficiency as per manufacturers specifications.

(C) CONDENSER WATER CIRCULATION SYSTEM: The condenser water circulation system shall be comprising of the following: (i) FRP induced draft cooling tower of total 110% plant working capacity suitable for above plant conditions complete with spray section, honey comb fill, basin, CT fan, TEFC Motor, intake bird screen and other accessories (Technical Specifications as per the manufacturer) (ii) HDPE make up water tank of 2,000 Litres capacity (1 No) installed on PCC/brick staging for makeup water requirement including brass float valve with polyethylene ball, over flow and drain arrangement, incoming connection of GI pipe 50mm bore medium grade from tank to tapping point including necessary cutting of existing pipe line and tapping of branch connections with GI pipe 25mm bore medium grade all as directed (The item rate is inclusive of provisioning all connected incoming pipe lines from existing sources and all outgoing) - 01 Job.

(iii) Energy saving Split casing type 3 Phase electric driven pump set of 50% capacity and discharge as per capacity of plant working on 415 Volts, AC, FASD starter for re-circulation of condenser water with ribbed rubber vibration isolation pads 03 Nos (02 Nos. working and 01 No. as stand by). 100 mm dia pressure gauges on both discharge and suction side of pumps shall be provided at the outlet of each pump (02 Nos working and 01 No stand by). Note: Pump Casing-Cast Iron, Impeller-Bronze/Cast Iron, Shaft-HSS or as per manufacturer, Material of Seal-Mechanical Seal. The condenser water pumps shall have minimum flow rate of 4.0 US GPM/TON respectively.

(iv) Condenser water MS Class 'C' tubing heavy grade of suitable size by electric arc continuous welding, including two coats of synthetic enamel paint over a coat of red oxide primer as per approved colour code fixed on supports, walls, floors etc. for connecting chiller package unit, pump sets and cooling tower, including filters, fittings, valves, pressure gauges, purge cocks at upper most position, blind flanges, strainers with bypass arrangements.

(D) CHILLED WATER CIRCULATION SYSTEM: The chilled water circulation system shall be comprising of the following: (i) Energy saving Split casing type 3 phase electric driven pump sets working on 415 Volts, AC for recirculation of chilled water of 50%, plant capacity-3 Nos. (Two Nos working and one No standby) including 100 mm dia pressure gauge shall be provided on delivery side of pumps including rubber vibration isolation pads for mounding including all connections complete. Note: Pump casing-Cast iron, Impeller-Bronze/Cast Iron, Shaft-HSS or as per manufacturer, Material of Seal-Mechanical seal. The chilled water pumps shall have minimum flow rate of 2.4 US GPM/TON.

(ii) Chilled water MS class 'C' tubing heavy grade of suitable size, fixed on supports, walls, floors etc for connecting chiller package units, pump sets, AHUs including fittings, valves, pressure gauges, purge cocks at upper most position, blind flanges, strainers joined by electric arc continuous welding all joints sealed with bitumen, laced with chilled water piping insulated with 50mm thick EPS pipe section of TF quality of density 16 KG/Cu.m and then cladded with aluminium sheet of 28 SWG thick or plastering using sand cement 15mm thick in two layers over chicken wire mesh where buried under earth. (iii) HDPE /PVC expansion tank of 2000 Litres capacity including pipe connections and insulation with 50 mm thick fibre glass wool covered with chicken wire mesh of density of 24 KG/Cu.m finished with sand cement plaster including civil works and painting with 3 coats of cement based paint and necessary piping, control valves on inlets and wash out, float valve etc.-01 .No.

(E) AIR TREATMENT SYSTEM: The air treatment system shall be comprising of the following:- (a) Design, supply, installation, testing and commissioning factory made high static double skinned horizontal type backward curved Air Handling Unit (AHU) with minimum 50mm static pressure with suitable CFM with 0.6mm thick pre-coated outer skin & 0.6mm thick inner skin made out of GI sheet not less than 22 gauge. The insulation with 25mm thick PUF panels. The AHUs will be floor mounting (with anti-vibration pads) for cooling the air with all accessories and controls comprising the following including painting etc as per standard practice: Notes:- (i) Static pressure may vary according to the design. (ii) The same should be got approved by the Accepting Officer and along with the number of AHU's and its CFM also.

(b) SITC hot water generator of suitable capacity for re-heat in monsoon. (c) Acoustic Insulation with 25 mm thick fibre glass rigid boards and finished with RP tissue paper and 28 mm gauge aluminium perforated sheet up to 5 m from outlet of the air plenum including 5 micron filters in air plenum for all AHUs all as specified and directed. (d) Fresh air damper with GI bowl/fittings and mosquito proof netting shall be provided for each AHU. (e) Under deck insulation in AHU Rooms with Fire retardant XLPE closed cell of thickness 18mm with metalized polyester film and self adhesive backing with protection peel off paper. (F) AIR DISTRIBUTION SYSTEM: The air distribution system shall be comprising of the following:

(i) Supply & Return Air ducting factory made out of commercial grade GI sheet zinc coating 120 grade, IS-277 and factory fabricated as per SMACNA-1995 standards and IS-655, but not less than 22 SWG thick. Ducting wherever passing through un-conditioned space shall be insulated with resin bonded Fibre Glass Wool 25 mm thick (density 24 Kg / Cum) covered with GI chicken wire mesh and cladded with aluminium foil fixed with adhesive tape. Where these ducts are exposed to the sky these will be insulated with 50mm thick fibre glass wool density 24 Kg / Cum, covered with polythene sheet faced Hessian cloth, GI chicken wire mesh and cladded with sand cement plaster-1 Job (ii) Aluminium powder coated double deflection adjustable type supply air grills/diffusers with MS volume control dampers and aluminium powder coated fixed bar type return air grills/diffusers as required without volume control damper, for return air -1 Job

(j) Provision of suitable heavy duty power capacitors to maintain PF value not less than 0.98 lagging. (ii) Electrical Panel Board for AHUs: Cubicle type floor mounted, vermin proof, dust proof as per IE standards, powder coated switch board panel made out of CRCA sheet not less than 2mm thick powder coated paint suitable for operation on 415 Volts, 50 Hz, AC supply internally wired with copper conductor wire comprising of the following:- (a) TPN Copper Busbar of suitable rating. (b) Main incoming MCCB of 25 KA rupturing capacity and suitable outgoing for AHU motor HWG and humidifier. (c) Voltmeter for 0-500 Volts digital type meter. (d) Ammeter of required rating digital type. (e) LED indicating lamps. (f) Starters with suitable rating/size, contactors, relays, SPP and glow type push button switches for AHU motor.

(H) Cabling: Necessary cable connection from main electrical panel to AHU, chilled machines, pump sets etc., i.e. for all the equipment in AC plant room and AHU motor, shall be with unarmoured copper conductor cables. The cables shall be laid in masonry trenches or overhead on cable trays on suitable supports at any distances shall be deemed to be included in the quoted rate. The department will provide only power supply source for taking the connection to the panel board in plant room. (J) Control Wiring: Refrigeration control wiring with copper conductor, PVC insulated, unsheathed, multistranded, 1100 Volts grade, single core of size 1.5 Sq.mm drawn in and including PVC conduit of suitable size for interlocking arrangement as per standard practice with thermostat, humidistat, balancing valve, blower motor, pumps, starter etc.,

(K) Earthing: Earthing of electric equipments with galvanised steel earth plate electrode 600 x 600 x 6 mm buried directly in ground earth pit not less than 2.25 m deep below normal ground level, connecting to and including GI strip 32 x 6 mm (up to the body of the equipment) by means of two GI bolts / nuts / washers. Earth plate shall be surrounded by packed layers of charcoal dust and common salt 15 cm thick all around bottom and top and watering pipe 50 mm dia projected 30 cm above the GL with one socket and removal GI plug on top and 2.25 m light grade perforated galvanised steel top with socket and plug and bottom connected to earth plate by slit and two bolts/nuts/washers. Earth strip shall be protected by 40 mm bore GI light grade pipe to test point/ equipment and including necessary earth work in any type of soil, GI pipe etc., minimum 16 Jobs is deemed to be included in the quoted rate.

Notes: The quored rate is deemed to be included for the following :- 1. All civil works required to install, test and commissioning the equipment such as earth work excavation, RCC foundation for equipment, necessary cable ducts with MS covers 10 mm thick duly painted, earth work excavation for laying pipe, cable etc & making good all disturbed/broken surfaces to match existing surface including fixing the ducting, painting / distemper /colour wash etc. 2. Necessary water supply pipe connections for the Expansion tank and A/C plant from existing water supply connection 3. All three phase motors shall provided independent single phasing preventor with phase reversal protection. 4. Manufacturers, technical back up after sales service support shall be provided for chiller package. 5. All loads up to 63 Amps shall be controlled by MCB and MCCB for loads above 63 Amps.

6. Suitable supports for holding the ducts and pipes will be provided by tenderer as specified and directed. The tenderer shall also examine at site the method of provision of supply ducts from AHU to entry of the building and inside the conditioned space and any columns / beams / angle iron frames etc. if required to support the ducts grills 7. Perforated GI sheet cable tray 100 mm width fixed on angle iron supports grouted in wall for carrying all cables shall be deemed to be included in the quoted rate. 8. Initial charging of oil and refrigerant. 9. Velocity of air in supply air duct shall not exceed 450 m / minute (1500 FPM) and velocity at diffuser outlet shall not exceed 150 m / minute (500 FPM). 10. Necessary drain connection at AHU room and AC plant room shall be provided by the tenderer.

11. Any work not included in the above details, but is an inescapable technical requirement for the efficient performance and smooth functioning of the plant shall be clearly specified and included in the offer. 12. Electric and water supply for Phase-I and Phase-II testing will be provided free of cost by the department. 13. COP (Minimum) for Chillers shall be 4.70. 14. The complete plant is to be installed, tested and commissioned only by the skilled engineer of the original Manufacturer of the chiller-packages. Necessary confirmation is to be submitted by the contractor after completion of the work with test certificates before dept undertakes further testing as per tender and cost is deemed to be included in the quoted rate. 15. All Equipment shall be connected with earth strip of size 32 x 6 mm.

16.01. The Contractor shall submit heat load calculations as per data sheet & building drawings enclosed with tender and design of Central Air Conditioning system along with the drawings, specifications for compressors, condenser water system with cooling tower, chilled water system, hot water generator supply system complete with pipelines, valves, controls etc. with proper colour coding and supply & return air duct with fire dampers as per STEC pamphlets complete. The design shall be carried out through OEM

16.02 The design shall be got approved by CWE before execution of work. The minimum tonnage capacity of plant shall not be less than 3 x 25 TR (2 x 25 TR as Working & 1 x 25 TR as Standby). For any higher variation in capacity of plant i.e. compressors with all connected accessories up to air distribution system as per approved design and no price adjustment shall be claimed and the rate quoted shall be deemed to be included for the same.

17. Phase-II Summer, Monsoon & Winter tests shall be carried out as specified in the Particular Specifications and testing officer to be nominated by accepting officer.Necessary arrangement shall be arranged by Contractor and quoted rate is deemed to be included. 18. After completion of Phase-I test, the plant shall be continuously run for 24 hours (three shifts of 8 hour each per day) by the contractor by providing services of one operator in each shift of 08 hours till completion of all the Phase-II tests and he shall be liable to carry out all the maintenance or repair or replacement of parts (if any) required during this period and quoted rate shall be deemed to be included for this provision.

19. Removal of all electrical fitting / fixtures from ceiling / wall and re-fixing the same after laying of duct and including making good of all dismantled surfaces along with provision of new point wiring (wherever damaged) complete as per existing size etc. 20. Distance marked between Magazine, AHUs and AC plant room on the site plan are approximate. Nothing extra will be paid for variation if any. Contractor shall visit the site to make themselves familiar with working conditions, accessibility of site, availability of materials, location of AHU and length and route of ducting required and other cogent condition etc before quoting the tender. Nothing extra shall be paid consequent to any mistake or misunderstanding or otherwise on this account.

21. Defect liability of 2 years after date of completion of the work. 22. The design, erection/installation of AC plant including connected accessories shall be as per final approval report/STEC pamphlets as specified in PS. 23. The rate quoted deemed to be inclusive for nearest higher available capacity of plant as per OEM recommendations and no extra shall be paid on this account. 24. Any missed out item which is related to complete the job and including testing & commissioning.