Goodmans DSX, GSZ, ASZ, SSX, ASX, DSZ, GSX MBR/AR*F with Single Stage Heat Pumps, Heating Operation

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SERVICING

1.4The compressor and condenser fan are turned off and after a 65 second delay off, the relay on the EBTDR board is de-energized and the blower is turned off.

2.0Heating Operation

2.1On a demand for heat, the room thermostat energizes “W1” and 24Vac is supplied to heat sequencer, HR1, on the heater assembly.

2.2The contacts M1 and M2 will close within 10 to 20 seconds and turn on heater element #1. The normally closed contacts on the EBTDR are also connected to terminal M1. When M1 and M2 close, the blower motor will be energized thru the normally closed contacts on the EBTDR board. At the same time, if the heater assembly contains a second heater element, HR1 will contain a second set of contacts, M3 and M4, which will close to turn on heater element #2.

Note: If more than two heater elements are on the heater assembly, it will contain a second heat sequencer, HR2, which will control the 3rd and 4th heater elements if available. If the first stage heat demand, “W1” cannot be satisfied by the heat pump, the temperature indoors will continue to drop. The room thermostat will then energize “W2” and 24Vac will be supplied to HR2 on the heater assembly. When the “W2” demand is satisfied, the room thermostat will remove the 24Vac from HR2. The contacts on HR2 will open between 30 to 70 seconds and heater elements #3 and #4 will be turned off. On most digital/electronic thermostats, “W2” will remain energized until the first stage demand “W1” is satisfied and then the “W1” and “W2” demands will be removed.

2.3When the “W1” heat demand is satisfied, the room thermostat will remove the 24Vac from HR1. Both set of contacts on the relay opens within 30 to 70 seconds and turn off the heater element(s) and the blower motor.

MBR/AR*F WITH SINGLE STAGE HEAT PUMPS

3.0 Cooling Operation

On heat pump units, when the room thermostat set to the cooling mode, 24Vac is supplied to “O” which energizes the reversing valve. As long as the thermostat is set for cooling, the reversing valve will be in the energized position for cooling.

3.1On a demand for cooling, the room thermostat energizes “G” and “Y” and 24Vac is supplied to “Y” at the heat pump and the “G” terminal on the EBTDR board.

3.2The heat pump turned on in the cooling mode and after a 7 second on delay, the relay on the EBTDR board is energized and the blower motor starts.

3.3When the cooling demand is satisfied, the room thermo- stat removes the 24Vac from “G” and “Y”.

3.4The heat pump is turned off and after a 65 second delay off, the relay on the EBTDR board is de-energized and the blower motor is turned off.

4.0 Heating Operation

On heat pump units, when the room thermostat set to the heating mode, the reversing valve is not energized. As long as the thermostat is set for heating, the reversing valve will be in the de-energized position for heating except during a defrost cycle. Some installations may use one or more outdoor thermostats to restrict the amount of electric heat that is available above a preset ambient temperature. Use of optional controls such as these can change the operation of the electric heaters during the heating mode. This sequence of operation does not cover those applications.

4.1On a demand for first stage heat with heat pump units, the room thermostat energizes “G” and “Y” and 24Vac is supplied to “Y” at the heat pump unit and the “G” terminal on the EBTDR board. The heat pump is turned on in the heating mode and the blower motor starts after a 7 second on delay.

4.2If the first stage heat demand cannot be satisfied by the heat pump, the temperature indoors will continue to drop. The room thermostat will then energize terminal “W2’ for second stage heat and 24Vac will be supplied to heat sequencer HR1 on the heater assembly.

4.3HR1 contacts M1 and M2 will close will close within 10 to 20 seconds and turn on heater element #1. At the same time, if the heater assembly contains a second heater element, HR1 will contain a second set of contacts, M3 and M4, which will close and turn on heater element #2. The blower motor is already on as a result of terminal “G” on the EBTDR board being energized for the first stage heat demand.

Note: If more than two heater elements are on the heater assembly, it will contain a second heat sequencer, HR2, which will control the 3rd and 4th heater elements if available. If the second stage heat demand, “W2” cannot be satisfied by the heat pump, the temperature indoors will continue to drop. The room thermostat will then energize “W3” and 24Vac will be supplied to HR2 on the heater assembly. When the “W3” demand is satisfied, the room thermostat will remove the 24Vac from HR2. The contacts on HR2 will open between 30 to 70 seconds and heater elements #3 and #4 will be turned off. On most digital/electronic thermostats, “W3” will remain energized until the first stage heat demand “Y” is satisfied and then the “G”, “Y”, “W2” and “W3” demands will be removed.

4.4As the temperature indoors increase, it will reach a point where the second stage heat demand, “W2”, is satisfied. When this happens, the room thermostat will remove the 24Vac from the coil of HR1. The contacts on HR1 will open between 30 to 70 seconds and turn off both heater element(s). The heat pump remains on along with the blower motor because the “Y” demand for first stage heat will still be present.

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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 CapacitorRELAY, Start 15A Resistance Check15B Capacitance Check 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 GE X13TM Motor Connections 16E Blower Performance Data16F Checking GE X13TM Motors 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 PumpsMBE/AEPF with Single Stage GSX, ASX and SSX Condensers 41 MBE/AEPF with GSX, SSX, ASX, DSXDefrost Operation 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 Formulas 61A Checking Heater Limit Controls61B Checking Heater Fuse Link Optional Electric Heaters 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 StaticStatic Pressure Drop Coil Static Pressure DropTotal External Static 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
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