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Model reference

Lennox 45F08

Heat Pump

2 documents23 error codes2 service modes

Available documentation

Service Manual

  • XP16 Series Service Literature24 pg
    Covers this model
  • XPG20 Series Service Literature36 pg
    Covers this model
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Error codes (23)

CodeMeaning
1Long Run Time2System Pressure Trip or Discharge Sensor Fault3Short Cycling4Locked Rotor5Open Circuit6Open Start Circuit7Open Run Circuit8Welded Contactor9Low VoltageDS2:Alternating FAST Flash / DS1:Alternating FAST FlashCoil sensor problemDS2:Alternating SLOW Flash / DS1:Alternating SLOW Flash5-minute anti-short cycle delay due to initial power up, safety trip, or end of…DS2:FAST Flash / DS1:OFFDischarge sensor lockoutDS2:FAST Flash / DS1:ONDischarge line temperature lockoutDS2:OFF / DS1:FAST FlashDischarge sensor faultDS2:OFF / DS1:OFFNo power (24V) to board terminals R & C or board failure.DS2:OFF / DS1:ONLow pressure lockoutDS2:OFF / DS1:SLOW FlashLow pressure faultDS2:ON / DS1:OFFHigh pressure lockoutDS2:ON / DS1:ONCircuit board failureDS2:Simultaneous FAST Flash / DS1:Simultaneous FAST FlashAmbient sensor problemDS2:Simultaneous SLOW Flash / DS1:Simultaneous SLOW FlashNormal operationDS2:SLOW Flash / DS1:OFFHigh pressure faultDS2:SLOW Flash / DS1:ONDischarge line temperature fault

Service modes (2)

  • Compressor Modulation Operational Check["Turn main power OFF to outdoor unit.","Adjust room thermostat set point above (heating) or below…
  • Defrost Board Test Mode["Ensure Y1 input is active (ON) and the O room thermostat terminal into board is inactive (heating…

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