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Discussion Starter · #1 ·
Alright guys when it comes to HVAC I don't know anything about it. That's the part I sub out! I know someone here can point me in the right direction. My entire unit stopped working so I checked the transformer for 24v and there was nothing. I went to get a new one and I put it in. My unit came on for a few seconds then went off and the transformer was smoking and now is blown again. I checked my thermostat, it works. My old transformer had a fuse in line on it and the new one didn't and I didn't put one on it. Could it have blown because of this or did I hook up the wires wrong? Possibly a short in my thermostat wire? I appreciate any advice, thanks.
 

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You likely have a direct short to common somewhere in the wiring. If you don't have an inline fuse, install one with the new transformer. It's relatively easy, but, you kinda need to know what you are doing. I would call one of the local supply houses and ask for a recommendation of a good hvac guy who will show you whats up, at a fair price. Knowing how to use a multi-meter would really be beneficial.
 

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Discussion Starter · #3 ·
I could install a new fuse. I know how to use a multimeter also. So would the short to common be in the wiring in the unit or before it reaches the unit?
 

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It's hard to say where. But a meter will help. Set the meter to omega, put one lead on the common terminal, put the other on the r, w, y, and g terminals. Or, you could remove the thermostat wires and low voltage wires to the ac. If you still are blowing fuses, the problem is likely inside of the unit.

Do you happen to have a dog that likes to chew on things?
 

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Discussion Starter · #5 ·
It's hard to say where. But a meter will help. Set the meter to omega, put one lead on the common terminal, put the other on the r, w, y, and g terminals. Or, you could remove the thermostat wires and low voltage wires to the ac. If you still are blowing fuses, the problem is likely inside of the unit.

Do you happen to have a dog that likes to chew on things?
Ha! I do have a dog but he doesn't chew. I checked outside first. I recent had the condenser replaced and it all looks good still. I guess I'll be hunting for awhile. Thanks!
 

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Just a thought, but check you wired the new transformer the right way round, is it possible you wired 110v to the 24v connections, that would cause it to smoke and burn out.
 
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