Kung Fu Maintenance shows the first things to check when your indoor house fan air conditioner or heater will not turn on HVAC.
HVAC Indoor House Fan Not Turning On
OK. Got an A/C that is not turning on. Going to flip it on. Flipped down to cool and auto. Lowered the temperature down here to 76. Now some thermostats have a five minute delay on it but this one not sure. So I went ahead and flipped the fan on to on. Problem is that’s not coming on either.
Unit should have kicked on. Let me show you one of the first things to check for. Well you can check your breakers. You know this one is on. Beyond that one of the first things to check for here. A lot of these service doors have a switch. You can see the door appears closed but if I push on this left side my theory is that it will kick on. And it looks like someone had a screw in here it has been partially taken out. So anyway.
Push on the left side. Unit kicks on. So what I need to do is just secure this screw in place and that was the purpose of it was to keep that safety switch engaged. These have sort of a mailbox latch that normally latches it into place but as they get older and a little worn sometimes they don’t always. Sometimes they’re a little too free. So this one looks like someone put a self tapping screw in it to secure the door. Anyway there we go. Now our AC has started to work. I can feel the line down here. The larger sized line right here starting to get nice and chilly. Good to go.
A/Cs working again. Just one of the first things to check for. Oh and same thing applies for if your heater wasn’t working it is the exact same deal. You know that service door switch if that is not engaged the house fan won’t turn on. The heater won’t turn on. The air condition won’t turn on. So it is just one of the first things to check for.
HVAC diagram from the book Kung Fu Maintenance