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jr0907
Dec 29, 2008, 07:40 PM
The heat does not come on nor does a/c I replaced the tstat I have power at the contacter and 120 v at transformer going in and I'm only getting 22v coming out I also replaced the transformer the unit is a Carrier and has a furnace for heat with a ignition spark module

letmetellu
Dec 29, 2008, 08:33 PM
22 volts is enough at the transformer. Now here is something for you to try.
Make sure that you door switch is taped so that it will supply power with the door off. At the low voltage terminal board in the furnace use a jumper wire to jump from the terminal marked R to the terminal marked W. This should start the heat cycle of your furnace.
If this does not start it then use the jumper and jump between the R terminal and the G terminal, this should cause the squirel cage blower to run.
If this does not do anything then you should start using a volt meter and start checking voltages at the gas valve and other switches. Looking for something that has power but does not work.

You said you replaced the thermostat, did you do this before or after the trouble started. If the trouble started after, then you need to check all of your wiring.