My attic air handling unit won't turn off - help (furnace, AC)
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I live in a relatively brand new house (2016) so expect fairly modern components. I have the main AC outdoor and a big air handling unit in the attic. For some reason, my air handling unit won't turn off and is constantly blowing air.
The weird thing is neither the AC nor fan are on. How do I know? If I go to a thermostat and turn AC on, I can hear the unit outside turn on and air gets cold. If I go to a thermostat and turn fan on, strong air starts blowing from the vents as expected. It's stuck in some like low air idle stage.
The most messed up thing, I flipped the attic & hvac breaker to my house and it still won't turn off...
Do you have the owners manual? You can usually get the info online if you have the model number. There is probably some kind if limit switch that is malfunctioning. Their should certainly be a breaker for that unit, but it may be mis-labeled.
if it is both there is usually a fan switch which turns the fan on when the air warms up and the heat is on . . if that sticks the fan will just run on it's own .
you really need to know if it is a heat cool unit or just cooling .
if it is both there is usually a fan switch which turns the fan on when the air warms up and the heat is on . . if that sticks the fan will just run on it's own .
you really need to know if it is a heat cool unit or just cooling .
Quote:
Originally Posted by Willamette City
Do you have the owners manual? You can usually get the info online if you have the model number. There is probably some kind if limit switch that is malfunctioning. Their should certainly be a breaker for that unit, but it may be mis-labeled.
Also, I do have the manual, but all manual says is it's a Goodman gas furnace. Also, I found the right breaker - hvac breaker = outdoors, furnace breaker = indoors. Still doesn't help fix the issue though...
those are what are called A coils and they typically use an existing heating systems fan to blow air through . it is a way of taking a hot air heating system and turning it in to a central ac system too .
if the ac is using the heating system blower , the problem is actually going to be in the heat circuit . specifically a stuck fan control or fan klixon .
when the heat is warm enough the fan control turns the fan on automatically so you don't get drafts before the air warms up . if that sticks closed the fan will not stop .
generally it is not going to be a easily spotted separate control , but rather a small thermo klixon disc that looks like a round piece of plastic .
Are you sure it is your AC and not a whole house attic fan?
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