Carrier 48VT(N) Troubleshooting, Start-Upchecklist, Unit Operation And Safety Hazard, 48VT--A

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UNIT OPERATION AND SAFETY HAZARD

ACCUMULATOR

COMPRESSOR

HP S

OUTDOOR COIL

INDOOR COIL

TXV in Bypass

Position

LCS

Metering￿

Position

LEGEND

HPS – High Pressure Switch

LCS – Loss of Charge Switch

Refrigerant SystemCompressor OilSynthetic Roof Precautionary Procedure Accurater®￿Metering De vice

Arrow indicates direction of flow

C03012

Fig. 26 - Typical Heat Pump Operation, Heating Mode

48VT-- A

!WARNING

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could result in personal injury or equipment damage.

This system uses Puron (R-410A) refrigerant which has higher operating pressures than R-22 and other refrigerants. No other refrigerant may be used in this system. Gauge set, hoses, and recovery system must be designed to handle Puron. If you are unsure, consult the equipment manufacturer.

Refrigerant System

This information covers the refrigerant system of the 48VT-A including the compressor oil needed, servicing systems on roofs containing synthetic materials, the filter drier and refrigerant charging.

Compressor Oil

If additional oil is needed use Uniqema RL32-3MAF. If this oil is not available, use Copeland Ultra 32CC or Mobil Artic EAL22CC. This oil is extremely hygroscopic, meaning it absorbs water readily. POE oils can absorb 15 times as much water as other oils designed for HCFC and CFC refrigerants. Take all necessary precautions to avoid exposure of the oil to the atmosphere.

Servicing Systems on Roofs and with Synthetic materials

POE (polyolester) compressor lubricants are known to cause long term damage to some synthetic roofing materials.

Exposure, even if immediately cleaned up, may cause embrittlement (leading to cracking) to occur in one year or more. When performing any service that may risk exposure of compressor oil to the roof, take appropriate precautions to protect roofing. Procedures which risk oil leakage include, but are not limited to, compressor replacement, repairing refrigerant leaks, replacing refrigerant components such as filter drier, pressure switch, metering device, coil, accumulator, or reversing valve.

Synthetic Roof Precautionary Procedure

1.Cover extended roof working area with an impermeable polyethylene (plastic) drip cloth or tarp. Cover an approximate 10x10 ft (3x3 m) area.

2.Cover area in front of the unit service panel with a terry cloth shop towel to absorb lubricant spills and prevent run-offs, and protect drop cloth from tears caused by tools or components.

3.Place terry cloth shop towel inside unit immediately under component(s) to be serviced and prevent lubricant run-offs through the louvered openings in the unit base.

4.Perform required service.

5.Remove and dispose of any oil contaminated material per local codes.

Liquid Line Filter Drier

This filter drier is specifically designed to operate with Puron. Use only factory-authorized components. Filter drier must be replaced whenever the refrigerant system is opened. When removing a filter drier, use a tubing cutter to cut the drier from the system. Do not unsweat a filter drier from the system. Heat from unsweating will release moisture and contaminants from drier into system.

Puron (R-410A) Refrigerant Charging

Refer to unit information plate and charging chart. Some R-410A refrigerant cylinders contain a dip tube to allow liquid refrigerant to flow from cylinder in upright position. For cylinders equipped with a dip tube, charge Puron units with cylinder in upright position and a commercial metering device in manifold hose. Charge refrigerant into suction-line.

TROUBLESHOOTING

Use the Troubleshooting Guides (See Tables 10-12) if problems occur with these units.

START-UP CHECKLIST

Use Start-Up checklist to ensure proper start-up procedures are followed.

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Contents SAFETY CONSIDERATIONS TABLE OF CONTENTSFig. 1 - Unit 48VT-A Installation InstructionsINTRODUCTION RECEIVING AND INSTALLATIONStep 1 - Check Equipment Step 2 - Provide Unit SupportFig. 2 - 48VT-A24-30Unit Dimensions 48VT--AA09146 Fig. 3 - 48VT-A36-60Unit Dimensions 48VT--AA09147 48VT Fig. 4 - Roof Curb DimensionsSMALL CURB ROOF CURB DETAILStep 5 - Rig and Place Unit ACCESS PANELS MUST BE IN PLACE WHEN RIGGINGInspection Rigging/Lifting of Unit See FigStep 8 - Install Gas Piping Step 7 - Install Flue HoodStep 6 - Connect Condensate Drain Fig. 6 - Condensate TrapConfiguring Units for Downflow Vertical Discharge Step 9 - Install Duct ConnectionsFig. 7 - Sediment Trap FIRE OR EXPLOSION HAZARDFig. 8 - Supply and Return Duct Opening Table 1 - Physical Data - Unit 48VT-A48VT--A Horizontal Duct CoversTable 2 - Maximum Gas Flow Capacity Table 1 - Physical Data - Unit 48VT-ACont’dTable 3 - Heating Inputs 48VT--ASpecial Procedures for 208-VOperation Step 10 - Install Electrical ConnectionsHigh-VoltageConnections Control Voltage ConnectionsPRE-START-UP Balance Point Setting-Thermidistator HybridTransformer Protection ThermostatSTART-UP Step 3 - Start-upHeating and Make Adjust- mentsStep 1 - Check for Refrigerant Leaks Step 2 - Unit Sequence of OperationFig. 11 - Burner Assembly Adjust Gas InputCheck Heating Control Check Gas InputCheck Burner Flame Limit SwitchesNormal Operation Airflow and Temperature RiseRollout Switch Step 4 - Start-upCooling and Make Adjust- mentsChecking and Adjusting Refrigerant Charge Indoor Airflow and Airflow AdjustmentsContinuous Fan Operation Gas Heating Fan Speed Set-upTable 6 - Color Coding for Indoor Fan Motor Leads 48VT--ATable 8 - 48VT-AWet Coil Pressure Drop Fig. 14 - Interface Fan Board IFB48VT--A Table 7 - Filter Pressure Drop Table IN. W.CUNIT 48VT--AHeating 48VT--A1295 48VT--A1445 48VT--A1448 48VT--A48VT A Fig. 15 - 208/230-1-60Wiring Diagram, Unit 48VT-AFig. 16 - 208/230-3-60Wiring Diagram, Unit 48VT-A 48VT--AA09209 48VT--A Fig. 17 - Cooling Charging Table-Subcooling50VT500173 REV A09099Cleaning the Blower Motor and Wheel MAINTENANCEAir Filter Indoor Blower and MotorInduced Draft combustion air Blower Assembly Limit SwitchFig. 18 - Blower Housing and Flue Collector Box Fig. 19 - Unit Access PanelsOutdoor Fan Electrical Controls and WiringRefrigerant Circuit Fig. 20 - Removal of Motor and Blower WheelLoss of Charge Switch Pressure SwitchesHigh-PressureSwitch Gas InputPage LCS - Loss of Charge Switch HPS - High Pressure SwitchFig. 24 - Refrigerant Circuit AccuraterMetering De viceSTART-UPCHECKLIST TROUBLESHOOTINGUNIT OPERATION AND SAFETY HAZARD Synthetic Roof Precautionary Procedure48VT--A PURONR R-410AQUICK REFERENCE GUIDE48VT--A SYMPTOMTable 12 - Troubleshooting Guide-Heating Table 13 - Troubleshooting Guide-LEDStatus Codes48VT--A I. PRELIMINARY INFORMATION MODEL NO Remove and Store in Job FilesTEMPERATURES PRESSURESCatalog No 48VT---05SI 48VT--AEdition Date 04/09 Replaces 48VT---04SI