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Quick air conditioner diagnostics and solutions you can do

It’s hot, the air conditioner is out, here’re some things you can do to get things working or at least to tell the AC guy you tried so they don’t try. Warning: turn off the breakers to the AC unit before trying anything. ANYTHING.

Air blowing weakly, outside fan spinning, cool air not happening

Check the coils outside – are they a block of ice? If yes then the unit has counterintuitively frozen up. This happens when either your inside filter is filthy, your outside coils are filthy (or have a random plastic bag stuck on them,) or your freon is low.

Your first thing to do here is turn the AC off – you’ve got a 100 pound block of ice outside that has to melt in order to let air through the unit again. In the temps we’re going to see that’s about a six hour melt.

Check the inside filter, if it’s filthy replace it. While you can technically clean your exterior coils I’m not going to advise you on how to do this as you could slightly kill yourself. If neither of these work you’ll probably need someone licensed to check the freon levels.

Unit off, thermostat has no display

I’ve now seen three digital thermostats in that were not powered by the AC systems, but instead by AA or AAA batteries.

While proper wiring would be supplying power to the thermostat negating the need of batteries, batteries tend to die about a year and a half after your honest tech came and performed a miracle and fled.

There’s a breaker in your house, and usually a breaker at the compressor. Turn it off and on again.

You have no air conditioner
Check to see if there’s actually an air conditioner still attached to your house. If not, someone may have wandered off with it.

Bad thermostat
Thermostats tend to go bad. If you’ve got a Honeywell thermostat chances are good you can run to Lowes or Home Depot and get the same stat.

That said, depending on what your air conditioner setup is this may or may not work.

Nest thermostat keeps shutting cooling off

A. You’ve got an ex who has your Nest thermostat added to their smartphone. Disconnect the Nest from WiFi until you can get that sorted out… Stacy.
B. check your schedules

Outside compressor comes on but fan won’t spin, spins slowly

a. Bad fan motor – replace fan and motor. Not terribly hard but you’ll find this out at 7pm on Saturday so HA HA. Seriously, it’s four screws and three wires.

b. Bad single or dual pole contactor – the part is $9-24 depending on what you get. It’s the most common element to go out. It’s what pulls down and completes the circuit to engage the fan and compressor. Cheap, easy to replace. Two screws and five to nine wires. Honestly forget. Easy to reach.

c. Bad control board – skip trying to diagnose this one.

d. Demons. Sometimes they pop up and want you to get a feel for the firey depths. In this case you can call anyone who claims to be an exorcist as AC demons aren’t particularly strict on religious qualifications.

Any of that work for you? Donate button’s on the left and down. Didn’t work? You never heard of me.

Paul King

Paul King lives in Nashville Tennessee with his wife, two daughters and cats. He writes for Pocketables, theITBaby, and is an IT consultant along with doing tech support for a film production company.