Goodmans GSZ, ASZ, DSZ, SSZ manual 41 MBE/AEPF with GSX, SSX, ASX, DSX, Defrost Operation

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SERVICING

4.5When the first stage heat demand “Y” is satisfied, the room thermostat will remove the 24Vac from “G” and “Y”. The heat pump is turned off and the blower motor turns off after a 65 second off delay.

5.0 Defrost Operation

On heat pump units, when the room thermostat is 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.

5.1The heat pump will be on and operating in the heating mode as described the Heating Operation in section 4.

5.2The defrost control in the heat pump unit checks to see if a defrost is needed every 30, 60 or 90 minutes of heat pump operation depending on the selectable setting by monitoring the state of the defrost thermostat attached to the outdoor coil.

5.3If the temperature of the outdoor coil is low enough to cause the defrost thermostat to be closed when the defrost board checks it, the board will initiate a defrost cycle.

5.4When a defrost cycle is initiated, the contacts of the HVDR relay on the defrost board open and turns off the outdoor fan. The contacts of the LVDR relay on the defrost board closes and supplies 24Vac to “O” and “W2”. The reversing valve is energized and the contacts on HR1 close and turns on the electric heater(s). The unit will continue to run in this mode until the defrost cycle is completed.

5.5When the temperature of the outdoor coil rises high enough to causes the defrost thermostat to open, the defrost cycle will be terminated. If at the end of the programmed 10 minute override time the defrost thermo- stat is still closed, the defrost board will automatically terminate the defrost cycle.

5.6When the defrost cycle is terminated, the contacts of the HVDR relay will close to start the outdoor fan and the contacts of the LVDR relay will open and turn off the reversing valve and electric heater(s). The unit will now be back in a normal heating mode with a heat pump demand for heating as described in the Heating Opera- tion in section 4.

S-41 MBE/AEPF WITH GSX, SSX, ASX, DSX

MBE ELECTRONIC BLOWER TIME DELAY RELAY AEPF AIR HANDLER

SEQUENCE OF OPERATION

This document covers the basic sequence of operation for a typical application with a mercury bulb thermostat. When a digital/electronic thermostat is used, the on/off staging of the auxiliary heat will vary. Refer to the installation instruc- tions and wiring diagrams provided with the MBE/AEPF for specific wiring connections, dip switch settings and system configuration.

MBE/AEPF WITH SINGLE STAGE GSX, ASX AND SSX CONDENSERS

When used with a single stage GSX, SSX and ASX condens- ers, dip switch #4 must be set to the on position on the VSTB inside the MBE/AEPF. The “Y” output from the indoor thermostat must be connected to the yellow wire labeled “Y/ Y2” inside the wire bundle marked “Thermostat” and the yellow wire labeled “Y/Y2” inside the wire bundle marked “Outdoor Unit” must be connected to “Y” at the condenser.

The orange jumper wire from terminal “Y1” to terminal “O” on the VSTB inside the MBE/AEPF must remain connected.

1.0Cooling Operation

1.1On a demand for cooling, the room thermostat energizes “G” and “Y” and 24Vac is supplied to “G” and “Y/Y2” of the MBE/AEPF unit. The VSTB inside the MBE/AEPF will turn on the blower motor and the motor will ramp up to the speed programmed in the motor based on the settings for dip switch 5 and 6. The VSTB will supply 24Vac to “Y” at the condenser and the compressor and condenser are turned on.

1.2When the cooling demand is satisfied, the room thermo- stat removes the 24Vac from “G” and “Y”. The MBE/AEPF removes the 24Vac from “Y’ at the condenser and the compressor and condenser fan are turned off. The blower motor will ramp down to a complete stop based on the time and rate programmed in the motor.

2.0Heating Operation

2.1On a demand for heat, the room thermostat energizes “W1” and 24Vac is supplied to terminal “E/W1” of the VSTB inside the MBE/AEPF unit. The VSTB will turn on the blower motor and the motor will ramp up to the speed programmed in the motor based on the settings for dip switch 1 and 2. The VSTB will supply 24Vac to heat sequencer HR1 on the electric heater assembly.

2.2HR1 contacts M1 and M2 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.

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.

For the 3rd and 4th heater elements to operate on a second stage heat demand, the PJ4 jumper on the VSTB inside the MBE/AEPF must be cut. With the PJ4 jumper cut, the VSTB will run the blower motor on low speed on a “W1” only demand. 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 and the blower motor will change to high speed. When the “W2” demand is satisfied, the room thermostat will remove the 24Vac from “W2” and the VSTB will

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Contents Service Instructions Important Information Recognize Safety SYMBOLS, Words and LabelsEmail us at customerservice@goodmanmfg.com 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 Cooling System OperationHeating Cooling CycleDefrost Cycle Heating CycleCooling Cycle System Operation AFE18-60A Control Board DescriptionTroubleshooting Chart COOLING/HP Analysis ChartServicing 61B3A Thermostat and Wiring Checking WiringChecking THERMOSTAT, WIRING, and Anticipator Checking Voltage3B Cooling Anticipator 3C Heating AnticipatorChecking Transformer Control Circuit Checking Time Delay RelayTesting Coil Circuit Checking Cycle ProtectorChecking Contactor AND/OR Relays Testing Compressor ContactorSingle Phase Checking Contactor ContactsCopeland Comfort Alert Diagnostics Testing FAN RelayDiagnostics Table Checking LOW Pressure Control Checking Loss of Charge ProtectorChecking High 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 17A Resistance Test Testing Compressor WindingsChecking Compressor 17B Ground Test17D Operation Test 17C Unloader Test ProcedureUnloader Test Procedure Compressor Ground TestTesting Defrost Thermostat Testing Crankcase Heater Optional ItemTesting Defrost Control Checking Reversing Valve and SolenoidChecking Heater Elements 40 MBR/AR*F Electronic Blower Time Delay RelayChecking Heater Limit Controls 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 Evacuation Leak Testing Nitrogen or NITROGEN-TRACEDRefrigeration Repair Practice Brazing MaterialsCharging EvacuationFinal Charge Adjustment Checking Compressor Efficiency105B Thermostatic Expansion Valve TXV ValvesPressure vs. Temperature Chart 410A Required Liquid Line Temperature Superheat OverfeedingUnderfeeding Checking SubcoolingFixed Orifice Restrictor Devices 109A TWO Speed ApplicationChecking Expansion Valve Operation Subcooling Formula = Sat. Liquid Temp. Liquid LineNON-CONDENSABLES Checking Restricted Liquid LineOvercharge of Refrigerant Compressor BurnoutLong Line SET Application R-410A Accessories for lines greater than 80 feetRefrigerant Piping 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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