View Full Version : Tried to install new thermostat
texasredhead
Jul 23, 2010, 07:40 PM
I am in desperate need of help.
I turned off my thermostat (not from the fuse box outside)---I unscrewed the box and the wires. I was going to try to install my new thermostat. The old unit is 7 wires and the new is 6, so I was completely confused, so I decided to put the old thermostat back on. While putting the old one back, two of the wires touched and sparked. Now nothing will work. I went out tot the fuse box and flipped that switch--then flipped the fuse in the attic. Still nothing. My husband just went out of town and he is going to be so upset with me.
Help!!
wmproop
Jul 23, 2010, 08:28 PM
Tell him a lot of men have done the same thing
You have fried the transformer with is inside the furnace/airhandler
This was done when you didn`t turn off the breaker to the furnace
Don`t know if you should attempt to find and replace the transformer,, let us know if you want to attempt a transformer swap-out
texasredhead
Jul 23, 2010, 08:44 PM
The sad thing is, I called an electrician friend and asked if I should flip the breaker--he said NO. Should have gone with my gut feeling. I went out and bought a new thermostat. You think for sure, I fried it when the two wires touched and sparked. Dang!! If replacing the transformer is fairly easy, I will sure try. I live in Texas and it's already hot in my house. Would it be expensive to have it fixed. Should I try the new thermostat---with the breakers off :)
KISS
Jul 23, 2010, 09:09 PM
I'm going to slightly disagree with wmproop.
1. You could have fried the transformer (one possibility)
2. There is sometimes a 3A automotive style fuse on the circuit board for the furnace. If it's installed, it should protect the transformer.
There should be a wiring diagram when you remove the access door. You might want to post a pic of that diagram using go advanced/manage attachments.
Not likely the thermostat.
texasredhead
Jul 23, 2010, 09:15 PM
Keepitsimple----So do you think I fried something?
texasredhead
Jul 23, 2010, 09:15 PM
Oh, and the house is only 7 years old. Does that make a difference on the transformer?
KISS
Jul 23, 2010, 09:21 PM
Either the fuse or the transformer. Transformers are typically 40 VA, 120 V primary and 24 V secondary. Mounting can be different. Depending on the furnace, they may have to be phased properly. Really means if the furnace generates a "reverse polarity" error, you switch the secondary wires.
texasredhead
Jul 23, 2010, 09:26 PM
I will get up in there in the morning and take pictures.
Thank god I have 3 fans to run tonight :)
KISS
Jul 23, 2010, 09:31 PM
Make and model number of furnace might help.
texasredhead
Jul 23, 2010, 09:51 PM
Lennox cb30M-46-1p??
wmproop
Jul 23, 2010, 10:25 PM
These numbers are for a heat pump, we need the numbers off the furnace/airhandler
texasredhead
Jul 23, 2010, 10:25 PM
I did see a sticker on the outside that said --component arrangement--is that the diagram?
Thank you so much for your help--you have no idea how much you are putting my mind at ease---i am enjoying learning all of this :)
I am a girlie girl, yet I prob should have been a man--I do all the manly things around the house and with our cars :)
texasredhead
Jul 23, 2010, 10:28 PM
these numbers are for a heat pump,,we need the numbers off the furnace/airhandler
What about
s/n 5803A 20330
The other number is the filter number--bmac-20ce
wmproop
Jul 23, 2010, 10:28 PM
I was thinking electric furnace/airhandler,,