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hongkong3
January 02, 2011, 14:56
I just got this email from my son and have no idea how to help him out as we're 3 1/2 hours apart. This after his dryer and fridg went out last week....... Can anyone tell me how to trouble shoot this?


Well...here's what 2011 brought to us; we discovered our gas furnace stopped working after we got home from our New Years gathering. That means no heat. Just went under the house and found the it's not getting any juice. Traced the line and found a transformer feeding it. Checked the voltage at the transformer and nothing. However the transformer is making a buzzing sound. So it's getting juice, it's just dead. Thank you 2011, way to roll in the new f***ing year.

Sig220
January 02, 2011, 16:26
Originally posted by hongkong3
I just got this email from my son and have no idea how to help him out as we're 3 1/2 hours apart. This after his dryer and fridg went out last week....... Can anyone tell me how to trouble shoot this?


Well...here's what 2011 brought to us; we discovered our gas furnace stopped working after we got home from our New Years gathering. That means no heat. Just went under the house and found the it's not getting any juice. Traced the line and found a transformer feeding it. Checked the voltage at the transformer and nothing. However the transformer is making a buzzing sound. So it's getting juice, it's just dead. Thank you 2011, way to roll in the new f***ing year.

I am not familiar with the system as described, but I would say that by the 'humming" that the transformer IS getting juice and if its not putting out it must be a dead/dying/bad transformer.......

Again, I probably know close to nothing about the furnace as described, but it looks like it has been diagnosed........now to find another transformer....

hongkong3
January 02, 2011, 16:31
Finding a transformer is going to be a pain since he can't find any id plates anywhere on the furnace. It's one of those old in the floor units from the 50's or earlier......

mike minihan
January 02, 2011, 17:38
Buy a Honeywell or White-Rogers transformer. Match up input and output
voltages,usually 120v in 24v out,there is also a va rating,replacement must
have the same or greater va rating. If it's a bum transformer this will fix it.


best regards,
Mike minihan

RG Coburn
January 02, 2011, 18:00
If it has a soleniod operated gas valve,there may be plate somewhere on it that lists it voltage.Most likely,its 24VAC.

L Haney
January 02, 2011, 20:38
Originally posted by RG Coburn
If it has a soleniod operated gas valve,there may be plate somewhere on it that lists it voltage.Most likely,its 24VAC.

Ditto. But, disconnect the 24 volt side first and check the voltage again. If something has shorted the wiring you won't see voltage and it will hum quite loudly. See 'em shorted by a homeowner hung a picture in the wrong place.

terral
January 02, 2011, 21:45
fuse your transformer when you replace it. use an automotive fuseholde with a 3 amp fuse if it blows locate the short cheaper replacing fuses than transformers

hongkong3
January 03, 2011, 13:10
Thanks for all the help, he found a new transformer for $13 and will install it later today.

Blood of Tyrants
January 03, 2011, 14:19
If the transformer doesn't help, check the rollout switch that will be near the burners. It is a small switch with two wires to it that has a button on it for resetting it. If it has tripped, the problem is likely a rusted out heat exchanger.

Look into the furnace and see if the heat exchanger tubes are rusted through. If so, then you will have to replace them. However, if you are handy with a MIG even better a TIG welder (or even a hammer and rivets), you can patch the rusted spots with some 16 gauge sheet metal. I have even replaced large portions of rusted round heat exchanger tube with muffler tubing. Make sure you use muffler mud to seal all the holes.

Taking out the heat exchanger can be a PITA but if you are short cash (like many of us are) it can be repaired if it isn't rusted out too badly.

hongkong3
January 03, 2011, 23:06
Well he checked it all out and it turned out to be a bad thermocouple, he picked on up at home depot for $10 and the furnace is running fine. Thanks again for all the advice!