Goodmans DSX Checking Transformer Control Circuit, Checking Cycle Protector, Testing Coil Circuit

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SERVICING

S-4 CHECKING TRANSFORMER

AND CONTROL CIRCUIT

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.

A step-down transformer (208/240 volt primary to 24 volt sec- ondary) is provided with each indoor unit. This allows ample capacity for use with resistance heaters. The outdoor sec- tions do not contain a transformer.

WARNING

Disconnect ALL power before servicing.

1.Remove control panel cover, or etc., to gain access to transformer.

With power ON:

WARNING

Line Voltage now present.

2.Using a voltmeter, check voltage across secondary volt- age side of transformer (R to C).

3.No voltage indicates faulty transformer, bad wiring, or bad splices.

4.Check transformer primary voltage at incoming line volt- age connections and/or splices.

5If line voltage available at primary voltage side of trans- former and wiring and splices good, transformer is inop- erative. Replace.

S-5 CHECKING CYCLE PROTECTOR

Some models feature a solid state, delay-on make after break time delay relay installed in the low voltage circuit. This control is used to prevent short cycling of the compressor under certain operating conditions.

The component is normally closed (R1 to Y1). A power interruption will break circuit (R1 to Y1) for approximately three minutes before resetting.

1.Remove wire from Y1 terminal.

2.Wait for approximately four (4) minutes if machine was running.

With power ON:

WARNING

Line Voltage now present.

1.Apply 24 VAC to terminals R1 and R2.

2.Should read 24 VAC at terminals Y1 and Y2.

3.Remove 24 VAC at terminals R1 and R2.

4.Should read 0 VAC at Y1 and Y2.

5.Reapply 24 VAC to R1 and R2 - within approximately three (3) to four (4) minutes should read 24 VAC at Y1 and Y2.

If not as above - replace relay.

S-6 CHECKING TIME DELAY RELAY

Time delay relays are used in some of the blower cabinets to improve efficiency by delaying the blower off time. Time delays are also used in electric heaters to sequence in multiple electric heaters.

WARNING

Disconnect ALL power before servicing.

1.Tag and disconnect all wires from male spade connec- tions of relay.

2.Using an ohmmeter, measure the resistance across terminals H1 and H2. Should read approximately 150 ohms.

3.Using an ohmmeter, check for continuity across termi- nals 3 and 1, and 4 and 5.

4.Apply 24 volts to terminals H1 and H2. Check for continuity across other terminals - should test continu- ous. If not as above - replace.

NOTE: The time delay for the contacts to make will be approximately 20 to 50 seconds and to open after the coil is de-energized is approximately 40 to 90 seconds.

OHMMETER

TESTING COIL CIRCUIT

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Contents Service Instructions Email us at customerservice@goodmanmfg.com Recognize Safety SYMBOLS, Words and LabelsImportant Information Fax us at 713 Fax us at 931 438Safe Refrigerant Handling Split System Heat Pumps R410A Product IdentificationModel # Description Split System Air Conditioners R410A ASX130**1AA Single Piece Air Handlers AWUF****1AA MBR/MBE Air Handlers Product Identification 1824 3642 ASX13 AccessoriesDSX/SSX16 ASX18 ASZ13 DSZ/SSZ16 ASZ18 Expansion Valve Kits FSK01A Coil Accessories Electric Heat Kitapplications Aruf Electric Heat Kitapplications Aepf Condensing Unit Product DesignFigure a Capacity Control Heating System OperationCooling Cooling CycleHeating Cycle Defrost CycleCooling Cycle System Operation Description AFE18-60A Control BoardCOOLING/HP Analysis Chart Troubleshooting Chart61B ServicingChecking THERMOSTAT, WIRING, and Anticipator Checking Wiring3A Thermostat and Wiring Checking Voltage3C Heating Anticipator 3B Cooling AnticipatorTesting Coil Circuit Checking Time Delay RelayChecking Transformer Control Circuit Checking Cycle ProtectorSingle Phase Testing Compressor ContactorChecking Contactor AND/OR Relays Checking Contactor ContactsTesting FAN Relay Copeland Comfort Alert DiagnosticsDiagnostics Table Checking High Pressure Control Checking Loss of Charge ProtectorChecking LOW Pressure Control Checking Capacitor15B Capacitance Check 15A Resistance CheckRELAY, Start 16B Checking FAN and Blower Motor ECM Motors 16A Checking FAN and Blower Motor Windings PSC MotorsChart on Next Chart from Previous 16C Checking ECM Motor Windings 16D ECM CFM Adjustments MBE / AepfCFM 16F Checking GE X13TM Motors 16E Blower Performance DataGE X13TM Motor Connections Checking Compressor Testing Compressor Windings17A Resistance Test 17B Ground TestUnloader Test Procedure 17C Unloader Test Procedure17D Operation Test Compressor Ground TestTesting Defrost Control Testing Crankcase Heater Optional ItemTesting Defrost Thermostat Checking Reversing Valve and SolenoidChecking Heater Limit Controls 40 MBR/AR*F Electronic Blower Time Delay RelayChecking Heater Elements Sequence of OperationHeating Operation MBR/AR*F with Single Stage Heat PumpsDefrost Operation 41 MBE/AEPF with GSX, SSX, ASX, DSXMBE/AEPF with Single Stage GSX, ASX and SSX Condensers 41A MBE/AEPF with Single Stage GSZ, SSZ, & ASZ Heat Pumps MBE/AEPF with TWO Stage ASX & DSX Condensers Sequence of OperationMBE/AEPF with TWO Stage ASZ & DSZ Heat Pump Units Electric Heater Optional Item 61B Checking Heater Fuse Link Optional Electric Heaters 61A Checking Heater Limit ControlsFormulas Refrigeration Repair Practice Leak Testing Nitrogen or NITROGEN-TRACEDEvacuation Brazing MaterialsEvacuation ChargingChecking Compressor Efficiency Final Charge AdjustmentTXV Valves 105B Thermostatic Expansion ValvePressure vs. Temperature Chart 410A Required Liquid Line Temperature Underfeeding OverfeedingSuperheat Checking SubcoolingChecking Expansion Valve Operation 109A TWO Speed ApplicationFixed Orifice Restrictor Devices Subcooling Formula = Sat. Liquid Temp. Liquid LineOvercharge of Refrigerant Checking Restricted Liquid LineNON-CONDENSABLES Compressor BurnoutRefrigerant Piping Accessories for lines greater than 80 feetLong Line SET Application R-410A Tube SizingInstallation Requirements Initial System Charging AIR Handler External StaticTotal External Static Coil Static Pressure DropStatic Pressure Drop ALL Fuel System AFE18-60A Control Board Accessories Wiring Diagrams10kw 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