How do I know what thermostat would be compatible with my furnace and air conditioner?

Question

I bought a new thermostat recently and hooked it up. I know the wiring is correct because I checked the wires all the way back to the furnace. The furnace is working, but the air conditioner will not turn on even though the wiring should be correct. I checked the filter, and that is clean. The only other option suggested to me was that maybe the thermostat wasn't compatible with my furnace/air conditioner. How do I know I'm getting the correct thermostat? I checked the manuals, and they don't say anything about a specific thermostat needed. The new thermostat I have didn't have any specifications that I noticed (as in: Only use with certain voltage of furnace/certain brand, ect.) How can I tell?

So if I 'jump' those two wires and the air conditioner doesn't come on with in 10mins, does that mean that something is wrong with my air conditioner? Besides the wiring being mixed up, can anyone think of anything else that might be the case for the furnace working but the air conditioner not?
(PS. Thanks for all the help! I really appreciate it since I can't afford to hire someone right now, and my hubby ISN'T a handyman sort!.)

Answer 1

Is there a cooling setting on the T-stat that needs to be turned on? Is your set point for cooling lower than your room temperature? Some T-stats have up to a five-minute delay prior to turning on the A/C.
Was the A/C working prior to the T-stat install? Check the cooling by taking the Y wire off the T-stat and touch the Y wire to the R terminal (or "jump" them with a jumper wire). If your AC comes on, the T-stat may be non-functional. Is not that uncommon.
You might have a Heat pump T-stat and a conventional system, or vice-versa.
If you jump the Y & R, the A/C should come on immediately. If not, you have a problem with your A/C unit. Don't let it run long, just long enough to see if the A/C comes on. If you don't get a response, check the breaker panel or fuse box to see if the breaker tripped or the fuse blew. If the breaker is tripped, reset it and try again. If it blows again, you have a problem that you will need to call a pro about. If you have power, and the A/C does not work, you will need to call a professional, or go without A/C. It is more than the homeowner can attempt.

Answer 2

I take it that you have a fossil fuel furnace w/air,Other than the wiring make sure that you dont or do have independant circuits for your system,some a/c condensers have their own transformer.If you only have 2 wires going to your outside unit,its a single transformer system and the only thing I can think of off hand is you might have terminals RH and RC on the stat that would need a jumper across the 2,hope this helpos,if thats not the case,can you post your wiring terminal letters and we can go from there

Answer 3

i've got replaced thermostats in properties equipped interior the final two decades, and it replaced into incredibly basic. i could be much less valuable what to assume if it is an older homestead (40+ years), yet at worst, you could in simple terms reconnect the previous one. in simple terms verify you tutor the means off to the furnace and AC and label which cord is going to which letter on the triumphing thermostat (you won't be waiting to have confidence the colour of the cord jacket). stable success!

Answer 4

you must mke sure that you installed the jumper on the thermostat,to get the correct thermostat look at your old one and check too make sure that it is set for 24 volts.