Handyguy Brian had the following conversation, via instant messaging, with his lovely wife (or so he thought) about how to troubleshoot a no display issue with a thermostat and no Air Conditioning (AC). No audio here.
Some steps for troubleshooting your AC, thermostat or heat.
Below is an actual conversation. The initial assumption was bad batteries in the thermostat but we learned through troubleshooting that the particular thermostat doesn’t need batteries, read on and find out how we got the thermostat back on and the air-conditioning working. There is a surprise at the end!
Sarah: Is there a reason there is no display on the air conditioning controls? It’s hot in here and I wanted to turn it on. It’s blank.
me: probably the batteries are dead in the thermostat. The cover should just pop off and I think 2 AA batteries.
Try that first. If that doesn’t bring it back to life we can then check the electrical panel for a tripped breaker. If that’s not it there are a few other things we can easily check.
Sarah: no batteries
there r no batteries
me: you sure??
Sarah: yes
me: hmmmmm
check the breaker box, there should be a breaker labeled AC or hvac or something, flip it off and then back on.
it’s probably a double breaker.
Sarah: ok brb
Sarah: nope didnt work
me: If that doesn’t do it, tell me what model number & manufacturer of thermostat we have
Sarah: i have no idea
me: It should say on the cover or something
honeywell xyzpdq123 or something
Sarah: the front says: White-Rodgers
me: okay, and a model ##?
Sarah: there isnt one on the front
me: k, hold on a min…
me: Model number should be on the inside of the front cover.
Sarah: u mean the “type #”?
me: yes
Sarah: 1F86-241
me: reset the thermostat by pressing <up>, <down> buttons and move the SYSTEM switch from OFF to HEAT at the same time.
Sarah: k but we want cold air
me: please do exactly that ^^^^
Sarah: k then do i put it to cool?
me: just do that and tell me if the display comes on
Sarah: kk
me: You are pressing and holding BOTH up and down buttons while moving the switch from off to heat
Sarah: i did that and it didnt work
me: okay, do these things…..
1) Double check all the breakers, turn every one off then on…
2) check the emergency shut-off switch at the top of the basement stairs, make sure someone didn’t mess with it.
Sarah: all of them?!
me: ALL of them
Sarah: the breakers
ugh
me: all of them
one at a time
Sarah: fine then check emergency switch?
me: yes, then….
3) check the service disconnect switch, it’s mounted on the side of the main unit in the basement, it’s a normal looking switch.
Sarah: k ill start with the breakers
brb
me: make sure no one messed with it, it should be on.
4) check the service access panel, it’s the cover that faces the red couch. There is a switch behind the cover that turns off the power if it’s removed. Make sure that cover is secure.
me: 5) In the basement, near the service disconnect switch, look for small thin wires, do they look like someone was messing with them? Maybe someone was putting something in that closet and knocked them and pulled one loose?
Sarah: what main unit?
the red switch is on i flipped and flipped all the circuit breakers one at a time so what is the main unit that has the normal looking switch
what is the main unit?
me: In the basement closet, the big beige thing
that all the ducts are connected to.
did anyone put stuff in there and maybe bumped the switch?
Sarah: ooo that thing kk brb
Sarah: nothing is in there that might have bumped it but it was off so i turned it on
me: hmmm, someone messed with it
did that fix the problem?
Sarah: yes thx u
me: whew
Sarah: now the house will get cooler
!!!!!!!
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me: one of the kids switched it
Sarah: y would they do that?
me: just to see what it would do
maybe they thought they would be turning on a light
A few minutes later…
Sarah: That was your daughter you were chatting with. I’ve been one the phone!
me: ahahhahah
she did all that?
^^^
Sarah: ye
yep
me: hahha
toooooooooo funny
me: I want to make a post from the chat! Its good info
Sarah: You are funny.
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How about that! Handyguy Brian’s 13 year old daughter was able to fix the air conditioning!
This is blog post only, no audio podcast.
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{ 4 comments… read them below or add one }
Funny! We have those conversations with people everyday. Good thing we know so many great servicemen to help them out. Thanks for sharing!
I went through all those steps and then saw that the drain hose came unhooked from the unit and the catch basin had filled with water. After I bailed enough water out, the unit restarted.
Good catch – Just make sure the drain is not clogged and the pump is working so you don’t have the issue again.
I followed these steps and figured out that the batteries were dead. I then had to reset the thermostat. Thank you for saving me a service call.