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jabird59
May 26, 2009, 07:44 PM
I accidentally cut my outside thermostat wires to my AC/Heating unit. I have reconnected the red wire only to the AC unit and the furnace and blower inside are working. However, the fan on the AC unit is not working, and thus no cold air. The thermostat wires is a CL2 wire with 5 smal wires. Since only the red and white are connected in the inside I only connected the red. Can anyone help?

hkstroud
May 26, 2009, 08:03 PM
Why didn't you reconnect the white. You have to have at least two wire to make a complete circuit to close the contactor.
Not only is your fan not working, your compressor is not working. Remove the cover plate and see what wires are connected to the contactor (device where the low voltage wires are connected) and see what color wires are connected to it. Reconnect those wires where you cut the low voltage cable. Note that is is also possible that you blew a fuse in the circuit panel on the inside when you cut the wires.

jabird59
May 26, 2009, 08:22 PM
Why didn't you reconnect the white. You have to have at least two wire to make a complete circuit to close the contactor.
Not only is your fan not working, your compressor is not working. Remove the cover plate and see what wires are connected to the contactor (device where the low voltage wires are connected) and see what color wires are connected to it. Reconnect those wires where you cut the low voltage cable. Note that is is also possible that you blew a fuse in the circuit panel on the inside when you cut the wires.


When, I connected the red and white together I blew the fuse again. I only have one wire coming from the AC/Heating unit which I connected the red wire to. Inside the furnace the red and white wire is connected. Of the white, green, blue, and yellow wires I am not sure which one to connect along with the red.

seanandanj
May 26, 2009, 08:55 PM
There should be 2 wires of the 5 connected inside your furnace, doesn't matter what color they are, just so long as they are connected the yellow and common screws. Yellow gets 24v when you call for cooling, and the other wire is the common. Under the service cover on the ac those 2 wires should connect to either side of the contactor, and pull it down which runs the ac when your stat calls for it. It is possible that when you cut the wire you jerked it and it is shorting out someplace else. Try switching from red and white to yellow and blue and see if the voltage makes it to its destination successfully. Also, you may want to turn off the 220v going to the AC before you pull the service cover so you don't zap yourself... good luck

dac122
May 27, 2009, 06:38 AM
Welcome to the place of repentant village idiots. Once you find the problem your penance will be to help others reform. :)

You will need the red (24VAC hot) and white (common/neutral) connected. If you are blowing a fuse you probably caused a short when you accidentally cut the wires.

Instead of wasting your time finding the short, just get yourself some 2 conductor wire of the same gauge and (re)run a new line from the air handler/furnace out to the A/C. Trust me, in the time it will take you to find the short you will have a new wire run and sipping on a cold one.

hkstroud
May 27, 2009, 08:07 AM
Well you don't connect the red and white wires together. Where you accidentally cut it, you connect the red to the red and the white to the white. If you don't have a white coming out of the A/C that means that you jerked it out when you cut it. What did you do? Run the lawn mower over it? dac122 is probably correct, it may be faster to just run new cable. Only need two wire cable.

jabird59
May 27, 2009, 08:26 AM
Well you don't connect the red and white wires together. Where you accidently cut it, you connect the red to the red and the white to the white. If you don't have a white coming out of the A/C that means that you jerked it out when you cut it. What did you do? Run the lawn mower over it? dac122 is probably correct, it may be faster to just run new cable. Only need two wire cable.


Thanks for the advice I will try just that. I did run over it with the mower. I opened the AC unit today and now I see (2) green wires one I connected the red wire to ( which got the furnace and blower back running) and from what you guys are saying I need to connect the same white wire to the other wire coming from the AC unit? Last quesiton, should the fan on the AC unit start running instantly or will it take some time before it starts to run?

seanandanj
May 27, 2009, 09:35 PM
The fan usually turns on the same moment that the compressor does unless it is a higher end unit with a pressure or temp sensor that will turn on the fan only when needed...