Goodmans DSZ, GSZ Checking Heater Limit Controls, Checking Heater Elements, Sequence of Operation

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SERVICING

3.Check the temperature at which the control opens its contacts by raising the temperature of the control. Part

# 0130M00009P which is used on 2 and 2.5 ton units should open at 60°F ± 5°F. Part # 0130M00001P which is used on 3 thru 5 ton units should open at 75°F ± 6°F.

4.If not as above, replace control.

S-26 CHECKING HEATER LIMIT CONTROL(S)

(OPTIONAL ELECTRIC HEATERS)

Each individual heater element is protected with an auto- matic rest limit control connected in series with each ele- ment to prevent overheating of components in case of low airflow. This limit control will open its circuit at approximately 150°F. to 160°F and close at approximately 110°F.

WARNING

Disconnect ALL power before servicing.

1.Remove the wiring from the control terminals.

2.Using an ohmmeter test for continuity across the nor- mally closed contacts. No reading indicates the control is open - replace if necessary. Make sure the limits are cool before testing.

IF FOUND OPEN - REPLACE - DO NOT WIRE AROUND.

S-27 CHECKING HEATER ELEMENTS

Optional electric heaters may be added, in the quantities shown in the spec sheet for each model unit, to provide electric resistance heating. Under no condition shall more heaters than the quantity shown be installed.

During a cooling or heat pump heating demand, 24Vac is supplied to terminal “G” of the EBTDR to turn on the blower motor. The EBTDR initiates a 7 second delay on and then energizes it’s onboard relay. The relay on the EBTDR board closes it’s normally open contacts and supplies power to the blower motor. When the “G” input is removed, the EBTDR initiates a 65 second delay off. When the 65 seconds delay expires the onboard relay is de-energized and it’s contacts open and remove power from the blower motor.

During an electric heat only demand, “W1” is energized but “G” is not. The blower motor is connected to the normally closed contacts of the relay on the EBTDR board. The other side of this set of contacts is connected to the heat sequencer on the heater assembly that provides power to the first heater element. When “W1” is energized, the sequencer will close it’s contacts within 10 to 20 seconds to supply power to the first heater element and to the blower motor through the normally closed contacts on the relay on the EBTDR. When the “W1” demand is removed, the sequencer opens it contacts within 30 to 70 seconds and removes power from the heater element and the blower motor.

The EBTDR also contains a speedup terminal to reduce the delays during troubleshooting of the unit. When this terminal is shorted to the common terminal, “C”, on the EBTDR board, the delay ON time is reduced to 3 seconds and the delay OFF time is reduced to 5 second.

Two additional terminals, M1 and M2, are on the EBTDR board. These terminals are used to connect the unused leads from the blower motor and have no affect on the board’s operation.

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.

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 instructions and wiring diagrams provided with the MBR/AR*F for specific wiring connections and system configuration.

1.Disassemble and remove the heating element(s).

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.

S-40 MBR/AR*F ELECTRONIC BLOWER TIME DELAY RELAY

The MBR/AR*F contains an Electronic Blower Time Delay Relay board, B1370735. This board provides on/off time delays for the blower motor in cooling and heat pump heating demands when “G” is energized.

MBR/AR*F WITH SINGLE STAGE CONDENS- ERS

1.0Cooling Operation

1.1On a demand for cooling, the room thermostat ener- gizes “G” and “Y” and 24Vac is supplied to “Y” at the condensing unit and the “G” terminal on the EBTDR board.

1.2The compressor and condenser fan are turned on and after a 7 second on delay, the relay on the EBTDR board is energized and the blower motor starts.

1.3When the cooling demand “Y” is satisfied, the room thermostat removes the 24Vac from “G” and “Y”.

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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 Capacitor15B Capacitance Check 15A Resistance 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 16F Checking GE X13TM Motors 16E Blower Performance DataGE 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 OperationDefrost 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 Sequence of Operation MBE/AEPF with TWO Stage ASX & DSX CondensersMBE/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 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 ChargingTotal External Static Coil Static Pressure DropStatic 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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