My AMANA (and another McQuay unit) in wall AC/heat pump unit works fine on cold days. However, I noticed when the room temperature is higher than the programmed temperature the heater starts letting in cold air. Ideally I would like it to just switch off until the room temperature drops below the programmed number. Is there anything I can do to achieve this desired behavior?

My unit looks is closed to this model but not exactly the same one

  • This is a thermostat control issue. Either switch the thermostat mode from "Auto" to "Heat" or increase the deadband between the heating and cooling setpoints.
    – user39367
    Jan 10 '17 at 16:50
  • i only have heat, cool, and fan modes. it's in heat mode and still does this. Is there anywhere else that I can change this?
    – awm
    Jan 10 '17 at 16:57
  • If it has only "heat" and "cool" then it should not be cooling in "heat" mode. If the the fan is set to "on" instead of "auto," that can feel drafty in some cases. With thermostat in "heat" and fan in "auto" there should be no air from the vents when the room temp > setpoint. If there is, then you have a malfunction of some type (duct work issues, incorrect control wiring, fused fan relay, etc -- no way of telling without some trouble shooting).
    – user39367
    Jan 10 '17 at 17:30
  • It could be the unit going into defrost mode if it happens right after it completes heating. Is it running continuously until it reaches a set temperature, or just for a short period of time?
    – Steve
    Jan 10 '17 at 18:42
  • 1
    If you have the owner's manual, you might find there is a fan delay setting causing the fan to run for a minute or two after the end of a heating cycle. It might be possible to disable that. Regarding startup, cold for awhile sounds like a typical heat pump in cold weather when not equipped with an indoor head pressure control. You might check if a cold weather indoor head pressure control is available for your unit. It's doubtful that is an aftermarket option.
    – user39367
    Jan 11 '17 at 4:06

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