Allied Air Enterprises 4HP16LT manual Maintenance

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MAINTENANCE

WARNING

Before performing maintenance operations on system, turn the electric power to unit OFF at disconnect switch(es). Unit may have multiple power supplies. Electrical shock could cause personal injury or death.

Before the start of each heating and cooling season, the following service checks should be performed by a qualified service technician.

Inspect and clean outdoor and indoor coils. The outdoor coil may be flushed with a water hose.

NOTE: It may be necessary to flush the outdoor coil more frequently if it is exposed to substances which are corrosive or which block airflow across the coil (such as pet urine, cottonwood seeds, etc...).

Visually inspect the refrigerant lines and coils for leaks.

Check wiring for loose connections.

Check voltage at the indoor and outdoor units (with units operating).

Check amperage draw at the outdoor fan motor, compressor, and indoor blower motor. Values should be compared with those given on unit nameplate.

Check, clean (or replace) indoor unit filters.

Check the refrigerant charge and gauge the system pressures.

Check the condensate drain line for free and unob- structed flow. Clean drain line, if necessary.

Adjust blower speed for cooling. Measure the pressure drop over the coil to determine the correct blower CFM.

Belt drive blowers: Check drive belt for wear and proper tensions.

If insufficient cooling is reported, the unit should be gauged and refrigerant charge checked (see Refrigerant Charging on page 12).

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Issue 1004

506468-01

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Contents 4HP16LT Series Torque Table Installation ClearancesGeneral Fastener TorqueSlab Mounting Electrical WiringSlab Mounting Roof MountingWithout Auxiliary Heat Thermostat DesignationsWith Auxiliary Heat Installing Refrigerant Line Outside Unit Placement InstallationBrazing Connection Procedure Refrigerant Line Sets Transition from Vertical to Horizontal Refrigerant Line Sets Installing Horizontal RunsR22 refrigerant will be used to flush the system Flushing Existing Line Set and Indoor CoilFlushing Connections Refrigerant Metering Device Liquid and Suction Line Service ValvesManifold Gauge Set Ball Type Service Valve Valve Open Service ValveTo Open Liquid or Suction Line Service Valve To Close Liquid or Suction Line Service ValveEvacuation Ambient temperature Refrigerant Charge AdjustmentRefrigerant Charging Cooling Cycle Charge Using Weigh-In MethodBlocking Outdoor Coil R410A Temperature/Pressure ChartNormal Operating Pressures Approach Values for TXV Systems Check Charge Using Normal Operating PressuresFilter Drier OperationSensor Temp. / Resistance Range Defrost Board Pressure Switch ConnectionsDelay Mode Issue Defrost Control Board Diagnostic LEDs Interpreting the Diagnostic LEDs System Diagnostic ModuleFlash Codes LED DescriptionShort Cycling 24VAC Power WiringThermostat Demand Wiring Miswired Module TroubleshootingMiswired Module Codes Maintenance Heat Pump Operation Case of extended power outageThermostat Operation Preservice Check Cooling Start-Up and Performance ChecklistHeating Sequence of OperationSingle Stage Wire Diagram Two Stage Wire Diagram