Need your help again guys. So you know what type of unit it concerns, it’s a Trane XE1200 Model# TWP030C100AM. Question: I’ve noticed that the AUX light seems to come on a lot lately. Outside temperature was 36 degrees. Of course, no ice or snow outside, on the unit or the coil. Inside thermostat set at 68 degrees. Unit came on at 8:53 a.m. AUX light came on at 9:06 a.m. Unit ran, with AUX light on until 9:21 a.m., then shut off. Larger copper pipe was warm in normal operation. smaller copper pipe was warm in AUX mode. I noticed before, that the AUX light would not come on as often. It seemed to only come on if you raised the inside temperature a few degrees. Which I considered normal. Now, it seems to come on every time the unit runs. Does it sound like an indoor or unit thermostat problem? Does it sound like a circuit board defrost problem? Does it sound like a compressor problem? I know I will need to call a service technician for a check up however, please, I would like to hear any and all thoughts you may have as to what may be causing the AUX light to come on so often? That way I can check for any problems myself prior to the call. And, when I call a technician out, I will know what questions to ask and be able to describe the situation better for him.

:wall: I am confused...Please someone point me in the right direction... 3 different technicians from 3 different companies are telling me 3 different things. My issue started when I noticed that my unit outside, the fan would run and run for hours at a time, non-stop. I have a DUEL FUEL system by the way... Electric heat pump is the primary, Natural gas in the attic is secondary. Heatpump is GMC unit I believe and is a 3 ton unit..The unit in the attic is a 4 ton and has a goodman coil 10 seer. My thermostat is a Honeywell ct-3600 digital thermostat with Em Heat-Heat-Cool 1st Tech: Tells me I don't need a duel fuel system, because gas is better. He suggested replacing the heat pump with just an ac unit outside, and replace the thermostat..outside to be a gmc 4 ton to match the coils inside. Because 3-ton unit outside is not correct, should be a 4 ton 2nd Tech: Tells me DUEL FUEL system is great keep that way...He recommends we replace the unit outside with a 3.5 ton Carrier 12 seer HeatPump and it will match the 4 ton unit inside that's 10 seer 3rd Tech: Pretty much says the same thing about DUEL FUEL...But he recommended that we match the goodman coil inside with a goodman heatpump...he says a 3ton heatpump is normally matched with a 4ton... Or I can go with a Lennox or Trane heatpump but he recommends we replace the coils to match the unit upstairs... I don't know who to believe...What do you guys think? Is it also a must that we match the coils inside with the same brand, will it really be that much more efficient? I live in Virginia Beach, VA by the way...I was quoted by the number 1 tech $2350 and number 2 tech $2594 for a 4 ton high efficiency carrier heatpump or $2454 3 ton high efficiency carrier heatpump 12seer....I don't know who to believe...I am very open to suggestions.