Hello, I have a Luxaire A/C system with an outside condenser and an air handler in my attic (model # faaf-f036ra). I have owned the house for 3 summers now and it's always worked perfectly. Early this year when we had the heat wave, I turned it on to make sure everything was working, and to my surprise, nothing happened. The fan wouldn't even turn on from the "on/auto" switch.
My initial concern was that a wire was disconnected or something (I had insulation blown in the previous fall, and there was power at the condenser and the thermostat). A few weekends later when it was cool I got ready to go up in the attic and dig around the air handler to check the wires from the tstat (it's all buried under insulation now). I quick switched the fan on before heading up and to my surprise, it started up. When I switched to cool mode, everything ran as it should.
I checked it a few more times over the last few weeks and it always came on. Imagine my surprise this last weekend when I turned it on to actually use it, and it was dead again (no fan, condenser, anything). No noises like anything was trying to start. Just - dead. I left the fan switch "on" and the tstat set to cool. About two hours later it started up and ran all weekend just fine.
My thought is this has something to do with heat. Both times it's been "dead" were hot, sunny days with outdoor temps near or at 90 deg. F. I imagine the attic is way hotter than that. I wondered about a high-temperature switch that would shut it down, or maybe the condensate pan overflow switch. What gets me is that it seems like the internal temps of the unit should be cooler since it's covered with insulation now. It seems like some sort of a switch because it's not like the condenser is starting up either. Another idea is the thermostat... which I could change out to rule out if/when this happens again.
Any thoughts would be greatly appreciated! Thanks in advance!