In my house, I have a thermostat close to the garage and when I open the interior door from the garage into my house and hot air briefly comes in, my thermostat seems to jump up from like 76 to 82 reading instantly. Then the thermostat doesnt readjust to the real room temperature, so it sits there trying to cool it down from 82 to 76 over many hours time, wasting A/C when the A/C doesnt need to be turned on. Besides relocating the thermostat what else can I do? Why would a draft of hot air instantly change the temperature but then the thermostat doesnt readjust immediately as that area is just hot for a brief moment?

 

How close is the thermostat to your garage door? Where is your garage door located compared to the rest of the house?

I know that when I open and close my garage door, it stays warm right next to the door for a while. There isn't a register in my hallway and the garage door is at the end of the hallway. One of the returns is in the hallway, but in the middle of the hallway (between the various rooms). So, air doesn't circulate very well at the end of the hallway.

You could try purchasing a new thermostat. Or you could try a thermostat guard/shield like thing...something like this:

http://www.homedepot.com/buy/buildin...l#.UBiBDshU2XQ

 

That won't resolve the issue that case, I'm reading now that the thermostat pulls the temperature from the wall its on, well since its on a wall where the other side of the wall is the garage, I guess its possible in the daytime (I live in 95 degree Florida weather), that the garage wall is getting hot and theres not enough insulation between the wall where even though the inside of my home is cool, the thermostat picks up the hot temperature from the wall? Is this a crazy thought?

 

NEST will solve all your problems!!!

 

fixed.

 

POS thermostat. Spend the money and get a good one. Mine is also located close to the garage door, but I never have your issue. I have a Commercial Vision Pro 8000 from Honeywell. It's fully programmable and doesn't get thrown off by those sudden temperature changes. In fact it learns your patterns and home's heat cycles. I highly recommend it. \/They make a residential model as well.

 

NEST for sure!

 

Nest will still be confused by the temp change I think.