How do I fix my A/C unit? There is no display reading on the unit!?

Question

I have turned off both the A/C and air handling circuit breakers for at least 15 minutes and that didn't work. The individual unit doesn't operate on a lithium battery so that's not it either. It was fully functional when I left home for vacation a week ago, and now the unit doesn't have a display showing. Help!

Answer 1

get a new thermostat

Answer 2

No display on the thermostat (unit?).

I am guessing you have a typical central air type unit.

The indoor unit supplies the control voltage to the thermostat so either there is no power to the indoor unit or possibly a control fuse that has blown or wiring or defective thermostat.

Without more info about what you have I am guessing.

Answer 3

I assume that you mean the thermostat has no reading on it. Check the wiring to the t-stat and then the t-stat wire to the air handler controller. Change the battery in the stat, or check hard wire connections. If all power sources to the t-stat are good, it may be defective and its easy to replace your self.

Answer 4

First thing you check before messing around with the t-stat would be the overflow float switch inside the air handler usually connected right by the drip pan(if it has one)..The way that this works is condensate in the line eventually creates slime sludge, and will eventually block the condensate, the water in the pipe wont drain, so instead of flooding your house it pushes up on the "float" switch killing the power to the t-stat. If this is the case you will need to clean the condensate line out with a wet/dry vacuum.

I really hope this helps it very well could be a ton of other things but this is the first thing I check, I check this even before I check the breaker cause it happens often.