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falcon753 10-21-2008 08:23 PM

Newly installed Thermostat doesn't power on
Hello to all,
I am new here and have some questions.
Today I received a replacement thermostat that I ordered last week. I had to replace it because my son thought he could kick his football in the house and in doing so he broke the old one off the wall. I am renting so I bought the exact same manufacturer and model number as we had before. When he broke it off I turned off the circuit breaker, it has been off for about 4-5 days. When I received the replacement one today I unscrewed each wire individually and connected to the similar connection on the new thermostat. After making sure everything was connected as before I flipped the circuit breaker back on but the new thermostat does not power on. I get no read out on the screen and after the last step (10. Turn on power to the unit.) the instructions say "On power up, the LCD readout will display H (heat only), C (cool only), HC (One Stage Heat-One Stage Cool) or HP (Heat Pump) depending on the thermostat model." I have a volt meter and every wire is receiving power but the thermostat isn't coming on . Am I doing something wrong or is a defective unit?

beenthere 10-21-2008 10:22 PM

can't tell from here.
Don't know what brand or model thermostat you have.
Or what wires you have where.
Or what wire you tested to what wire to see if you have power.

dac122 10-22-2008 08:24 AM

And what's the voltage? Much more info needed...

falcon753 10-22-2008 05:56 PM

I have a White wire connected to a W.
A Green wire connected to a G.
Red wire connected to an R.
Blue wire connected to a C.
And a Yellow one connected to a Y.
When I touch the Red wire with the + on my volt meter and the Blue wire with the - it reads 0. I made a mistake by saying they were getting power on my last post. sorry. I have been told that newer models A/C units have a 4 amp fuse somewhere that probably popped when it fell off the wall. I cannot find this fuse. The thermostat model is a Totaline P374-0200. My A/C unit is a Goodman. The house we are renting was built about 1 year ago.
If any other info can help I will gladly provide it if I can figure it out. Thanks

biggles 10-22-2008 05:56 PM

do you have a true 24Vs at the subbase from the furnace R to C,and whats the model/brand of stat,and was it an exact change-out?that 4amp fuse should be on the TR or mounted on a board but someplace within the furnace..i thought that also the football hit might of caused a short and knocked the fuse out.quick go from R to G on exposed subbase for fan .....should get a spark thats 24Vs closing the relay down in the air handlers

falcon753 10-22-2008 06:17 PM

The thermostat is a Totaline model P374-0200. This was the exact same brand/model that was installed before. I have not tested any other wires as of yet. One reason is b/c I cannot find my furnace. I have only lived in this house for 3-4 months. I think it might be in my attic but I cannot get up there.

beenthere 10-23-2008 05:05 AM

If its in the attic, there will be an access to it somewhere.

biggles 10-23-2008 06:45 AM

if you have a grill in the ceiling of the attic floor its up there if you have no filter in it wonder what condition the filter inside the unit is in.if the return grill is on the lower wall below your stat or in that area it could be in a closet or the can still do that R to W jump at the subbase to see if you get a reaction.

DangerMouse 10-23-2008 07:13 AM

if you have renter's insurance, call a pro to find the problem and fix it. the football may have broken a wire inside the sheathing and that line is now dead? just a couple thoughts.... i don't get many.


dac122 10-23-2008 07:33 AM

Since R and C have no power and if it turns out you have no fuse it is possible you fried the transformer that supplies power to your tstat. Swapping the transformer isn't too bad just be sure there are no pinched/split wires.

Get your son a Nerf football for Christmas.

DangerMouse 10-23-2008 07:46 AM

wouldn't the thermostat be part of the furnace unit that he does not know where it is?
and don't forget to get the kid a Nerf baseball and a Nerf frisbee, and...and...and....
a velcro wall and suit might help keep the kid out of trouble too...... just don't forget to feed him once in a while..... lol


falcon753 10-24-2008 06:12 PM

I know where the access is to my attic, but I don't have a ladder tall enough to crawl up there. My filters are located in the same hallway as my tstat,and they are located on the ceiling. I have checked all closets as well as my garage none containing the furnace which leads me to believe it is in the attic and the house does not have a basement.

DangerMouse 10-24-2008 06:19 PM

the filter on the ceiling should be a clue....
find that ladder....


hvaclover 10-24-2008 06:24 PM

Sounds like you need a PRO>

TheOak 10-27-2008 09:18 AM

When there is no power ... go for the obvious ...

The thermostat does not require batteries does it?

Did you flip on the correct circuit breaker?

Another idea is you could try going to Home Depot or Lowes or the like and getting a basic thermostat there. If you can get the Home Depot thermostat to work then your "replacement" thermostat was dead on arrival.

Otherwise, as previously suggested, if you have renter's insurance ... get someone in ...

You could always contact the owner too ... s/he might be an HVAC expert?

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