Carrier RHS, RVS, RDS006-060, RVR Unit Start-Up Cooling Mode, Operating Limits 50RHC,RVC Units

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Operating Limits

ENVIRONMENT — This equipment is designed for indoor installation ONLY. Extreme variations in temperature, hu- midity and corrosive water or air will adversely affect the unit performance, reliability and service life.

POWER SUPPLY — A voltage variation of ± 10% of nameplate utilization voltage is acceptable.

UNIT STARTING CONDITIONS — Depending on the model, units start and operate in an ambient temperature of 45 F with entering-air temperature at 40 F or 50 F, entering- water temperature at 20 F or 50 F and with both air and water at the flow rates used.

NOTE: These operating limits are not normal or continuous operating conditions. Assume that such a start-up is for the purpose of bringing the building space up to occupancy temperature. See Tables 18 and 19 for operating limits.

When the disconnect switch is closed, high voltage is present in some areas of the electrical panel. Exercise caution when working with the energized equipment. Failure to heed this warning could lead to personal injury.

1.Restore power to system.

2.Turn thermostat fan position to ON. Blower should start.

3.Balance airflow at registers.

4.Adjust all valves to the full open position and turn on the line power to all heat pump units.

5.Operate unit in the cooling cycle. Refer to Tables 18 and 19 for unit operating limits.

NOTE: Three factors determine the operating limits of a

unit: (1) entering-air temperature, (2) water temperature and

(3)ambient temperature. Whenever any of these factors are at a minimum or maximum level, the other two factors must be at a normal level to ensure proper unit operation. See Tables 18 and 19.

Scroll Compressor Rotation — It is important to be certain compressor is rotating in the proper direction. To determine whether or not compressor is rotating in the prop- er direction:

1.Connect service gages to suction and discharge pressure fittings.

2.Energize the compressor.

3.The suction pressure should drop and the discharge pressure should rise, as is normal on any start-up.

If the suction pressure does not drop and the discharge pressure does not rise to normal levels:

1.Turn off power to the unit. Install disconnect tag.

2.Reverse any two of the unit power leads.

3.Reapply power to the unit and verify pressures are correct.

The suction and discharge pressure levels should now move to their normal start-up levels.

When the compressor is rotating in the wrong direction, the unit makes more noise and does not provide cooling.

After a few minutes of reverse operation, the scroll com- pressor internal overload protection will open, thus activating the unit lockout. This requires a manual reset. To reset, turn the thermostat on and then off.

NOTE: There is a 5-minute time delay before the compressor will start.

Unit Start-Up Cooling Mode

1.Adjust the unit thermostat to the warmest position. Slowly reduce the thermostat position until the compres- sor activates.

2.Check for cool air delivery at unit grille a few minutes after the unit has begun to operate.

3.Verify that the compressor is on and that the water flow rate is correct by measuring pressure drop through the heat exchanger using P/T plugs. See Table 20. Check the elevation and cleanliness of the condensate lines; any dripping could be a sign of a blocked line. Be sure the condensate trap includes a water seal.

4.Check the temperature of both supply and discharge wa- ter. Compare to Table 21. If temperature is within range, proceed. If temperature is outside the range, check the cooling refrigerant pressures in Table 21.

5.Check air temperature drop across the coil when com- pressor is operating. Air temperature drop should be between 15 and 25 F.

Table 18 — Operating Limits — 50RHC,RVC Units

AIR LIMITS

50RHC,RVC

Cooling

Heating

 

Min. Ambient Air – db

45 F

45 F

Rated Ambient Air – db

80.6 F

68 F

Max. Ambient Air – db

110 F

85 F

Min. Entering Air – db/wb

70/61 F

50 F

Rated Entering Air – db/wb

80.6/66.2 F

68 F

Max. Entering Air – db/wb

95/76 F

80 F

WATER LIMITS

 

 

Min. Entering Water

50 F

50 F

Normal Entering Water

60-90 F

60-70 F

Max. Entering Water

110 F

90 F

Normal Water Flow

2.5-3.0 gpm per ton

LEGEND

 

 

db — Dry Bulb wb — Wet Bulb

Table 19 — Operating Limits — 50RHR,RHS,RVR,RVS,RDS Units

AIR LIMITS

COOLING (F)

HEATING (F)

Min. Ambient Air

45

45

Rated Ambient Air

80

70

Max. Ambient Air

100

85

Min. Entering Air

50

40

Rated Entering Air db/wb

80/67

70

Max. Entering Air db/wb

110/83

80

WATER LIMITS

 

 

Min. Entering Water

30

20

Normal Entering Water

50-90

30-60

LEGEND

 

 

db — Dry Bulb wb — Wet Bulb

NOTE: Value in heating column is dry bulb only. Any wet bulb read- ing is acceptable.

Table 20 — Water Temperature Change

Through Heat Exchanger

 

COOLING

HEATING

WATER FLOW RATE (GPM)

RISE (F)

DROP (F)

 

Min

Max

Min

Max

For Closed Loop: Ground Source or

9

12

4

8

Cooling/Boiler Systems at 3 gpm/ton

 

 

 

 

For Open Loop: Ground Water Systems at

20

26

10

17

1.5 gpm/ton

 

 

 

 

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Contents Safety Considerations ContentsGeneral InstallationPage PSC FAN Motor and Blower Physical Data Aquazone 50RHC,RVC006-060 UnitsPhysical Data Aquazone 50RHR,RVR006-060 Units Physical Data Aquazone 50RHS,RVS,RDS015-070 UnitsPermanent Split Capacitor Airflow Configuration Code Return DischargeRight Depth Height Out Pump Supply Ensate Ext Power Cond Therm Supply Return015-024 030Right Back Back RightTypical Installation 50RHC,RHR,RHS Units Right Top TopConfiguration Left Return Left View Configuration Top View-Left ReturnIsometric ViewIsometric View Configuration Left Return Left View Air Coil OpeningCode Front ViewReturn/Bottom Discharge Isometric View Ht Return/Bottom DischargeTop View Front-ViewSide Discharge Remove ScrewsRotate Move to Side50RHC Units Mounting the Unit50RHR Units 50RHS UnitsHorizontal Unit Pitch Condensate DrainCondition Acceptable Level Field Control Wiring Field Power Supply WiringBMC LOCNEC ComprRVS Typical Aquazone Deluxe D Control WiringHpws LONTrans A50-8154 Low Voltage Field Wiring RLA LRA Motor Unit Circuit FUSE/HACR 50RHC,RVC Electrical DataFLA RLA50RHR,RVR Electrical Data 50RHR,RVR VOLTS-PHASE Voltage Compressor FAN Total MIN MAXUnit Circuit Units RLA LRA FUSE/HACR50RDS, RHS, RVS Electrical Data PRE-START-UP50RHR,RVR Blower Performance 50RHR,RVR Rated MIN FANSpeed 50RVC Blower Performance with Hot Water Reheat HWR Option 50RHC,RVC Blower PerformanceReheat External Static Pressure ESP Loss Coil Face Velocity 50RHC,RVC Rated MIN FAN50RHS,RVS,RDS Blower Performance 50RVC Blower Performance with Wet CoilCoil Face Velocity WET Coil Reduction 50RHS,RVS,RDS Rated FANField Selectable Inputs Control Jumper Settings See Fig50RHS, RVS Blower Performance with HWR Coil Face 50RHS, RVS with Reheat ESP LossDIP Switch Block S2 Accessory 2 Relay Options DIP Switch Block S2 Accessory 1 Relay OptionsHumidistat/Dehumidistat Logic Deluxe D DIP Switch Settings Accessory DIP Switch Position Relay OptionsSTART-UP Control Accessory Relay ConfigurationsHWR Operating Modes OutputWater Temperature Change Through Heat Exchanger Unit Start-Up Cooling ModeOperating Limits Operating Limits 50RHC,RVC UnitsTypical Unit Operating Pressures and Temperatures Unit Start-Up Heating ModeEntering Cooling Heating Water GPM Temp F TON50RHR,RVR Coaxial Water Pressure Drop 50RHS,RVS,RDS Coaxial Water Pressure Drop50RHC,RVC Coaxial Water Pressure Drop Antifreeze Percentages by Volume Approximate Fluid Volume gal Per 100 Ft of PipeOperation Units with Aquazone Complete C ControlComplete C Control LED Code Fault Descriptions Units with HWR OptionSystem Test Service Aquazone Deluxe D Control LED IndicaESD Gravity Flow Method Troubleshooting Refrigerant ChargingAir Coil Fan Motor Removal Fault Heating Cooling Possible Cause Solution TroubleshootingUnit Does Not Operate II. START-UP 50RHC,RVC,RHR,RHS,RVR,RVS,RDS START-UP ChecklistCooling Cycle Analysis Heating Cycle Analysis
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