Goodmans DSZ Refrigeration Repair Practice, Leak Testing Nitrogen or NITROGEN-TRACED, Evacuation

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SERVICING

2.Using an ohmmeter, test across the fuse link for continu- ity - no reading indicates the link is open. Replace as necessary.

NOTE: The link is designed to open at approximately 333°F. DO NOT WIRE AROUND - determine reason for failure.

S-62 CHECKING HEATER ELEMENTS

WARNING

Disconnect ALL power before servicing.

1.Disassemble and remove the heating element.

2.Visually inspect the heater assembly for any breaks in the wire or broken insulators.

3.Using an ohmmeter, test the element for continuity - no reading indicates the element is open. Replace as necessary.

BRAZING MATERIALS

IMPORTANT NOTE: Torch heat required to braze tubes of various sizes is proportional to the size of the tube. Tubes of smaller size require less heat to bring the tube to brazing temperature before adding brazing alloy. Applying too much heat to any tube can melt the tube. Service personnel must use the appropriate heat level for the size of the tube being brazed.

NOTE:The use of a heat shield when brazing is recommended to avoid burning the serial plate or the finish on the unit. Heat trap or wet rags should be used to protect heat sensitive components such as service valves and TXV valves.

Copper to Copper Joints - Sil-Fos used without flux (alloy of 15% silver, 80% copper, and 5% phosphorous). Recom- mended heat 1400°F.

Copper to Steel Joints - Silver Solder used without a flux (alloy of 30% silver, 38% copper, 32% zinc). Recommended heat - 1200°F.

S-100 REFRIGERATION REPAIR PRACTICE

DANGER

Always remove the refrigerant charge in a proper manner before applying heat to the system.

When repairing the refrigeration system:

HIGH VOLTAGE!

Disconnect ALL power before servicing or installing. Multiple power sources may be present. Failure to do so may cause property damage, personal injury or death.

1.Never open a system that is under vacuum. Air and moisture will be drawn in.

2.Plug or cap all openings.

3.Remove all burrs and clean the brazing surfaces of the tubing with sand cloth or paper. Brazing materials do not flow well on oxidized or oily surfaces.

4.Clean the inside of all new tubing to remove oils and pipe chips.

5.When brazing, sweep the tubing with dry nitrogen to prevent the formation of oxides on the inside surfaces.

6.Complete any repair by replacing the liquid line drier in the system, evacuate and charge.

S-101 LEAK TESTING

(NITROGEN OR NITROGEN-TRACED)

WARNING

To avoid the risk of fire or explosion, never use oxygen, high pressure air or flammable gases for leak testing of a refrigeration system.

WARNING

To avoid possible explosion, the line from the nitrogen cylinder must include a pressure regulator and a pressure relief valve. The pressure relief valve must be set to open at no more than 150 psig.

Pressure test the system using dry nitrogen and soapy water to locate leaks. If you wish to use a leak detector, charge the system to 10 psi using the appropriate refrigerant then use nitrogen to finish charging the system to working pressure, then apply the detector to suspect areas. If leaks are found, repair them. After repair, repeat the pressure test. If no leaks exist, proceed to system evacuation.

S-102 EVACUATION

WARNING

REFRIGERANT UNDER PRESSURE!

Failure to follow proper procedures may cause property damage, personal injury or death.

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Contents Service Instructions Recognize Safety SYMBOLS, Words and Labels Email us at customerservice@goodmanmfg.comImportant Information Fax us at 713 Fax us at 931 438Safe Refrigerant Handling Product Identification Split System Heat Pumps R410AModel # Description Split System Air Conditioners R410A ASX130**1AA Single Piece Air Handlers AWUF****1AA MBR/MBE Air Handlers Product Identification 1824 3642 Accessories ASX13DSX/SSX16 ASX18 ASZ13 DSZ/SSZ16 ASZ18 Expansion Valve Kits FSK01A Coil Accessories Electric Heat Kitapplications Aruf Electric Heat Kitapplications Aepf Product Design Condensing UnitFigure a Capacity Control System Operation HeatingCooling Cooling CycleDefrost Cycle Heating CycleCooling Cycle System Operation AFE18-60A Control Board DescriptionTroubleshooting Chart COOLING/HP Analysis ChartServicing 61BChecking Wiring Checking THERMOSTAT, WIRING, and Anticipator3A Thermostat and Wiring Checking Voltage3B Cooling Anticipator 3C Heating AnticipatorChecking Time Delay Relay Testing Coil CircuitChecking Transformer Control Circuit Checking Cycle ProtectorTesting Compressor Contactor Single PhaseChecking Contactor AND/OR Relays Checking Contactor ContactsCopeland Comfort Alert Diagnostics Testing FAN RelayDiagnostics Table Checking Loss of Charge Protector Checking High Pressure ControlChecking LOW Pressure Control Checking Capacitor15A Resistance Check 15B Capacitance CheckRELAY, Start 16A Checking FAN and Blower Motor Windings PSC Motors 16B Checking FAN and Blower Motor ECM MotorsChart on Next Chart from Previous 16D ECM CFM Adjustments MBE / Aepf 16C Checking ECM Motor WindingsCFM 16E Blower Performance Data 16F Checking GE X13TM MotorsGE X13TM Motor Connections Testing Compressor Windings Checking Compressor17A Resistance Test 17B Ground Test17C Unloader Test Procedure Unloader Test Procedure17D Operation Test Compressor Ground TestTesting Crankcase Heater Optional Item Testing Defrost ControlTesting Defrost Thermostat Checking Reversing Valve and Solenoid40 MBR/AR*F Electronic Blower Time Delay Relay Checking Heater Limit ControlsChecking Heater Elements Sequence of OperationMBR/AR*F with Single Stage Heat Pumps Heating Operation41 MBE/AEPF with GSX, SSX, ASX, DSX Defrost OperationMBE/AEPF with Single Stage GSX, ASX and SSX Condensers 41A MBE/AEPF with Single Stage GSZ, SSZ, & ASZ Heat Pumps Sequence of Operation MBE/AEPF with TWO Stage ASX & DSX CondensersMBE/AEPF with TWO Stage ASZ & DSZ Heat Pump Units Electric Heater Optional Item 61A Checking Heater Limit Controls 61B Checking Heater Fuse Link Optional Electric HeatersFormulas Leak Testing Nitrogen or NITROGEN-TRACED Refrigeration Repair PracticeEvacuation Brazing MaterialsCharging EvacuationFinal Charge Adjustment Checking Compressor Efficiency105B Thermostatic Expansion Valve TXV ValvesPressure vs. Temperature Chart 410A Required Liquid Line Temperature Overfeeding UnderfeedingSuperheat Checking Subcooling109A TWO Speed Application Checking Expansion Valve OperationFixed Orifice Restrictor Devices Subcooling Formula = Sat. Liquid Temp. Liquid LineChecking Restricted Liquid Line Overcharge of RefrigerantNON-CONDENSABLES Compressor BurnoutAccessories for lines greater than 80 feet Refrigerant PipingLong Line SET Application R-410A Tube SizingInstallation Requirements AIR Handler External Static Initial System ChargingCoil Static Pressure Drop Total External StaticStatic Pressure Drop Accessories Wiring Diagrams ALL Fuel System AFE18-60A Control Board10kw and Below, One Stage Electric Heat OT/EHR18-60 #2 GRD PLM PLF XFMR-R XFMR-C After Installing Optional Heat KIT, Mark AN X Provided Above HKR Heat Kit GRD PLM PLF
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