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Installation, Operation and Maintenance Manual

VariCool

®

 VAV

5

Subject to change without notice.

10.20-IM (0818)

The electrical hazard icon indicates the presence of an electrical hazard which 

could result in electrical shock or death

The warning icon indicates a potentially hazardous situation which could result 

in death or serious bodily injury if not avoided

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ELECTRICAL 

HAZARD

WARNING

CAUTION

INFORMATION

Important Notice

This publication includes warnings, cautions and information icons that point out safety related issues or conditions as well 

as other pertinent information relative to a safe installation, service or maintenance situation The following icons should be 

interpreted as follows:

This manual is the property of the owner� 

Please be sure to leave it with the owner when you leave the job�

Use of Symbols

NOTE: If  the  unit  design  was ordered specific to the 

application or installation, please refer to the Addendum 

at the end of this product literature� The unit may have 

features or options specific to this  job or application so 

please  refer to the addendum for details� The addendum 

will  also  list  the  specific  United  CoolAir  Job  Number 

or  field  reference  Job  Name.  Examples  of  unit  design 

specific to unit ordered will include product dimensions, 

special control sequences and remote condenser / 

condensing sections�

Summary of Contents for AVW08

Page 1: ...VariCool VAV Installation Operation and Maintenance Manual Effective August 2018 Water Cooled and Chilled Water Variable Air Volume ...

Page 2: ......

Page 3: ...mote Alarm Output Option 16 Remote Water Pump Option 16 O A Damper Control Option 16 Smoke Detector Fire Stat Option 16 Remote On Off Control Option 16 SEQUENCE OF OPERATION 16 MARVEL PLUS CONTROLLER 16 Maintenance Procedures 17 Filters 17 Cleaning The Water Cooled Condenser 17 Blowers 17 Blower Motors 17 Blower Speed Adjustment 18 Blower Bearing Lubrication 18 Belts 18 Refrigerant Systems 19 Evap...

Page 4: ...roll to the footer section or Home industry resources enter your serial number in the Serial Search field and press return to retrieve your product wiring diagram Your serial number is a combination of the year month and sequential order of build date This action will return the Model number Job Number and the wiring diagram for viewing as well as downloading NOTE Only units shipped since November...

Page 5: ...otice This publication includes warnings cautions and information icons that point out safety related issues or conditions as well as other pertinent information relative to a safe installation service or maintenance situation The following icons should be interpreted as follows This manual is the property of the owner Please be sure to leave it with the owner when you leave the job Use of Symbols...

Page 6: ...oose in one or several boxes in the compressor section HANDLING Use extreme caution so that damage does not occur when moving each section to the location of installation The unit may be moved to the location of installation by crane fork lift hand truck or roller bars Units are provided with lifting rings for rigging and movement by crane Spreader bars must be used to protect section cabinet stru...

Page 7: ... UNIT DIMENSIONS Figure 2 Unit Dimensions and Table 2 show the dimensions of each unit section Note If the System has the Water Side Economizer Coil option the unit will have a fourth section that will be attached onto the Cooling Coil Return Air Inlet end of the unit This has been labeled with the dimension Tx on the diagram and it will vary depending on the filter options desired FIGURE 1 Servic...

Page 8: ...6 8 21 TBD TBD 21 5 20 TBD 5 50 AV 10 40 AV 12 18 32 7 18 AV 16 AV 20 80 80 35 35 48 32 20 36 7 5 22 TBD TBD 21 40 TBD 5 66 AV 24 60 AV 26 44 18 AV 30 AV 32 98 100 52 62 36 30 42 11 29 1 5 97 4 80 10 5 4 5 86 AV 36 AV 40 AV 44 52 24 AV 48 AV 52 AV 56 AV 60 Tx Filter Rack dimensions are as follows T1 7 width when a standard 2 Filter is ordered T2 9 5 width with extra filtration option includes a 2 ...

Page 9: ... unit the weight of each optional component must be added to the standard VariCool unit weight shown in Table 3 MODEL BLOWER lbs EVAPORATOR lbs CONDENSER lbs TOTAL lbs AVW08 588 521 592 1701 AVW10 617 550 642 1809 AVW12 699 562 732 1993 AVW16 757 619 796 2172 AVW20 1134 856 910 2900 AVW24 1270 954 1046 3270 AVW26 1305 954 1196 3455 AVW30 1305 989 1216 3510 AVW32 1735 1256 1697 4688 AVW36 1787 1325...

Page 10: ...tion isolator into positions shown in Figure 3 and then move the compressor and cooling coil section into the location of installation being careful not to damage the quick connect refrigerant piping 5 Fasten the cooling coil section bottom half to the compressor section using the mounting hardware removed in Step 2 6 Allow the hardware to remain only hand tight until the Blower Section is install...

Page 11: ...k connect couplings as loose fittings will restrain full refrigerant flow 13 Move the Blower Section into position of installation making sure the side that the blower can be seen will mate up with the large opening in the Cooling Coil Section 14 Lift the blower section up onto the Compressor Section 15 Use the remaining mounting hardware to connect the Blower Section to the Cooling Coil Section 1...

Page 12: ...08 10 AVW40 120 6 AVW44 132 7 AVW48 144 8 AVW52 162 10 AVW56 168 12 AVW60 180 14 Recommended Field Installed Externally Condensate Drain Connection Each VariCool unit has a condensate drain connection on the Cooling Coil section For systems with the Water Side Economizer coil option condensate drain connections are provided A condensate drain trap must be field fabricated and installed onto the 1 ...

Page 13: ...ound conduct must be connected from Earth Ground to the factory supplied ground lug internal to the unit SENSOR FIELD MOUNTING WIRING All sensors and optional components that must be field installed and wired to the electrical control panel must be wired as shown on the electrical diagram provided with the unit and the instructions listed below Static Pressure Transducer The static pressure transd...

Page 14: ...t the drain wire to ground at the VariCool s electrical control panel end only Return Air Temperature Sensor Option The Return Air Temperature Sensor is provided for units with the Morning Warmup option If the unit has the Airside Economizer option or optional Humidification Dehumidification a Humidity Sensor will also be provided The unit ReturnAir Sensor must be field installed in the return air...

Page 15: ... supply air duct at least in diameter 16 Using a 7 64 drill bit drill the three fastening screw holes located on the template for the fastening ring 17 Remove the duct sensor s mounting ring from the duct probe and position it over the holes previously drilled in the duct 18 Use three 6 x Pan Head sheet metal screws and fasten bracket to the duct 19 Place the probe into the supply air duct 20 Use ...

Page 16: ...the device and wired back to the VariCool s Control Panel Terminate from the device contact termination points to the factory provided terminals TB2 18 and TB2 19 Remote On Off Control Option With the Remote On Off Control option the unit will start when a voltage free dry contact closure is provided to Terminals TB2 20 and TB2 21 This closure may be provided by a field provided building managemen...

Page 17: ...ddressed Cleaning a water cooled condenser helps to improve the heat transfer rate reduce operational cost restore efficiency prolong heat exchanger life and reduce pressure drop pumping costs Deposits from water or water treatments such as scale lime rust or mud are removed Each installation is unique Therefore the fluid quality and operating conditions will dictate when the heat exchanger needs ...

Page 18: ...efore adding grease so as not to introduce dirt into the bearing Slowly rotate the shaft while pumping it in Pump the grease in slowly so as not to blow out the bearing seal When the grease starts to seep out of the bearing you have put in enough new lubricant Over lubricating can cause a bearing to fail from overheating or it can blow out the seal Both excessive or inadequate grease may cause pre...

Page 19: ...ircular dot in the center of the sight glass If the color of this indicator is blue the refrigerant is okay When the indicator is pink or purple an abnormal condition exists servicing is required INFORMATION After installation and during equipment start up the sight glass may appear pink or purple This occurs during prolonged periods of non operation and should turn blue after several hours up to ...

Page 20: ...e cycles through a cool down period usually 2 3 minutes A compressor off cycle timer is included in the electrical circuit for this purpose The time delay also helps the refrigerant system pressures to equalize at the end of the run cycle This helps the compressor during the starting process in that it is not attempting to start against a high discharge pressure INFORMATION Verify that this timer ...

Page 21: ... following sequence is based on the unit being controlled by a suitable room thermostat If another control type is being utilized reference the instructions for that device a Lower thermostat set point to lowest level b Set System switch to OFF position c Set Fan switch to the AUTO position d Moving the Fan switch to the ON position should cause the evaporator blower motor to run Moving the Fan sw...

Page 22: ...d recharge refrigerant system Check condenser for obstructions and remove Check for the required water flow through the water regulating valve and the condenser coil Manually reset thermostat With Marvel turn off alarm and reset Wait for PTCR to cool off Compressor should start in 3 5 minutes Stop unit and troubleshoot power supply and compressor circuit for low voltage Please note that it may tak...

Page 23: ...ed compressor bearings Liquid slugging Excessive head pressure Ensure thermal expansion valve bulb is tight on suction line Con firm that bulb is located properly on suction line Check operation and superheat Replace compressor Replace compressor System overcharged Reclaim excess refrigerant from the high side of the system Reduce head pressure see item 8 below 7 System short of capacity Flash gas...

Page 24: ...ed 10 Suction pressure too low Flash gas in liquid line bubbles in sight glass due to a leak Obstructed expansion valve Loss of fluid within expansion valve bulb Clogged filter drier Ice or dirt on evaporator coil Evaporator blower running backwards Repair leak and recharge Repair or replace valve Replace power head and valve Replace with new filter drier Defrost and clean evaporator coil and repl...

Page 25: ...ve freely Dirt or algae not allowing float to activate pump Locate and repair electrical connection problem Clean pump and float Clean pump and float 15 Condensate Pump runs with no discharge Tubing blocked or kinked Check valve blocked Inpeller blocked Tubing elevation or run exceeds head capability Inspect clean or straighten as necessary Clean check valve Remove debris from pump impeller Verify...

Page 26: ...ide of condenser and evaporator 9 Damages resulting from I freezing of condenser water or condensate II use of corrosive water III fouling or restriction of the air water circuit by foreign material or like causes 10 Damages resulting from operation with inadequate or interrupted supply of air or water 11 Damages resulting from use of components or accessories not approved by United CoolAir 12 Thi...

Page 27: ... or like causes 10 Damages resulting from operation with inadequate or interrupted supply of air or water 11 Damages resulting from use of components or accessories not approved by United CoolAir 12 This warranty does not apply to the installation plumbing and wiring not integral to the product 13 Damages resulting from improper application or sizing This warranty is in lieu of all other warrantie...

Page 28: ...Air 12 This warranty does not apply to the installation plumbing and wiring not integral to the product 13 Damages resulting from improper application or sizing of unit 14 In the event that the refrigerant type is changed as a result of a compressor failure and the same type of compressor is not available any subsequent refrigerant circuit component failures will not be covered under the Limited W...

Page 29: ...ssories not approved by United CoolAir 12 This warranty does not apply to the installation plumbing and wiring not integral to the product 13 Damages resulting from improper application or sizing 14 Discharge air temperature control if not provided by the factory will void the compressor Limited Warranty 15 In the event that the refrigerant type is changed as a result of a compressor failure and t...

Page 30: ...looded condenser option the scroll compressors will have crankcase heaters If the outdoor ambient is 70 F or lower let the compressors sit for approximately 24 hours before proceeding 12 Record the voltage at the unit terminals 13 If possible with the thermostat provided switch the evaporator blower to the RUN position Verify that the evaporator blower is activated 14 Verify that the evaporator bl...

Page 31: ...pressures on each compressor circuit are within the proper limits i 290 550 Discharge ii 100 140 psig Suction b Compressor Amperage is below the RLA Amps listed on the unit data tag i The maximum compressor operating current amps at start up depends a lot on the system loading The lower the load the less the current The higher the load the higher the current c The blower motor FLA values should ne...

Page 32: ...tact the Distributor Is the Circuit Protection the correct type and does it meet the unit data tag requirements Yes ____________ No ____________ If not correct describe what action s have been taken to correct Unit controller wiring verified Yes ____________ No ____________ C Terminal hooked up if necessary Yes ____________ No ____________ Unit leak checked OK Yes ____________ No ____________ If l...

Page 33: ...________ F_________ F_________ F_________ Sub cooling _________ _________ Electrical Evap Motor Amps L1_____________ L2____________ L3_____________ Compressor 1 Amps L1_____________ L2____________ L3_____________ Compressor 2 Amps L1_____________ L2____________ L3_____________ Cond Motor Amps L1_____________ L2____________ L3_____________ Heating Mode Optional System Air Temperatures Return F ____...

Page 34: ... for approximately 24 hours before proceeding 12 Record the voltage at the unit terminals 13 If possible with the thermostat provided switch the evaporator blower to the RUN or ON position Verify that the evaporator blower is activated 14 Verify that the evaporator blower is rotating in the correct direction three phase units only Note If the evaporator blower motor runs backwards shut off all pow...

Page 35: ...nding to the liquid line pressure 32 Calculate and record the liquid sub cooling for each circuit by taking the difference between the liquid line temperature and the saturation temperature corresponding to the liquid line pressure 33 Record the Amps for the evaporator blower motor and each compressor If the system is single phase use L1 and L2 only a Make sure the pressures on each compressor cir...

Page 36: ...r Is the Circuit Protection the correct type and does it meet the unit data tag requirements Yes ____________ No ____________ If not correct describe what action s have been taken to correct Unit controller wiring verified Yes ____________ No ____________ C Terminal hooked up if necessary Yes ____________ No ____________ Unit leak checked OK Yes ____________ No ____________ If leak was located des...

Page 37: ...ssor 2 Suction Pressure Suction Line Temperature psi________ F_________ psi________ F_________ Saturation Temperature F_________ F_________ Suction Superheat _________ _________ Liquid Line Pressure psi________ psi________ Saturation Temperature Liquid Line Temperature F_________ F_________ F_________ F_________ Sub cooling _________ _________ Electrical Evap Motor Amps L1_____________ L2_________...

Page 38: ...36 40 44 48 52 56 60 d G Common to all e X Indicate Voltage 3 4 or 5 3 208 230V 3 PH 4 460V 3 PH 5 575V 3 PH f A or D Indicates number of Refrigerant Circuits A Two Refrigerant Circuits D Four Refrigerant Circuits g XXX Indicates Nominal KW Rating for Electric Heaters From 10 KW to 150 KW Electric Heaters h T L or R Indicates Air Path Configuration T Top Supply Air L Left Side Supply Air When faci...

Page 39: ...Installation Operation and Maintenance Manual VariCool VAV 39 Subject to change without notice 10 20 IM 0818 NOTES ...

Page 40: ...Installation Operation and Maintenance Manual VariCool VAV 40 Subject to change without notice 10 20 IM 0818 NOTES ...

Page 41: ... on the compressor labor not included Maintenance items such as filters and belts are excluded under this limited warranty FACTORY TESTED All units are functionally run tested before shipment to ensure a trouble free start up and unit commissioning Industry proven components are used throughout to enhance system reliability and peace of mind VertiCool Classic Vertical 3 30 Ton VertiCool Aurora Ver...

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