buzzing sound, maybe transformer?

[tjfreemanjr]

I noticed a new buzzing sound at my furnace in the basement today. I doubt I will be able to get a serviceman out here until after the holidays, thought I might get some feedback from the forum and see what I might be dealing with first. The buzzing sound is present when the unit is on of in standby waiting to come on. If I take both covers off, the sound quits (becuase the safety switch is disengaged) and as soon as I depress the switch the noise starts back. I think I have tracked it down to a transformer, and when I disconnec the power wires from the transformer the sound immediately stops. Is this something that will be a fire hazard or will it just stop working one day?

Thanks for your input and time!

[hvaclover]

Could be nothing, but then I am not there, so I can't tell for sure.

Have it checked out by a local pro.

[dhvac]

some will always make noise some wont if you want to know for sure have it checked by someone that can see it

did this just start or did you just notice it?

[frigetater]

a good tech will know what to do to solve this....make the call or live with it

[tjfreemanjr]

Thanks for the feedback! As I stated, I will be calling a tech out to the house after the holidays. It always made a slight buzzing sound that you could barely hear with the covers on. A couple days ago this sound got much louder, maybe 10 times louder.

Thanks!

[deme]

I had two 'buzzing' problems.
The first one was a loud one occasionally coming out of the heat pump condenser. Opened the beast up and traced the noise to the reversing valve coil. Put my finger on it and the buzzing stopped.
The second one was in the furnace. Put my finger on the 120v/24v transformer and felt the 60 Hz vibration. Noisy transformer.

[tjfreemanjr]

Ok, let me go check it out. Was the transformer ok, just noisy?? Or didn you end up getting it replaced?

Thanks again

[corny]

Tighten the screws holding the transformer down to the cabinet...

[firecontrol]

Buzzing from a transformer just means that the laminations (small metal plates glued together making up the core) have somehow come unglued and are vibrating at 60hz against one another. This happens to some after time and isn't a danger. I'd probably replace it though due to the added heat this condition can cause inside of the transformer that can after time make it fail. Of course nothing EVER fails at a good time. If you get the equipment serviced every year I'd tell the service company that you'd like it replaced on the next schedueled service.

[hvaclover]

Yeah, the lamination's can come loose but tightening the mounting screws won't help too much,

You might consider this: If the transformer is buzzing, it might be because it doesn't know the words.

Pa rum pa pa! Thank you very much:D:D:(

[corny]

Ive silenced many many transformers since the early 80s by either tightening or loosening the mounting screws.

In 20 plus years Ive never replaced a transformer that died because of its design....its always been either because of human error or wiring problems.... Transformers just dont go bad..... Im sure a few might make it thru the factory with some defect and Im sure many die because of heat deteriorating the insulation but this heat is most likely caused by overoading the transformer.... some human putting too much of a load on it...

As far as loose laminations... thats a common problem but its pretty much a noise problem only.... those laminations are usually held together by an insulator such as varnish or lacquer and occasionally some laminations may break loose and cause hum but this does not affect the operation of the transformer to the point where heat is generated..... You want to generate heat...take a transformer apart and sand off the insulating film then put it back together...lol
it will get hot fast because you then basically have one large mass of metal for a core....

...But some transformers are bolted together or welded you jackass....

when you see a transformer bolted together or welded together on the corners...it doesnt really make the laminations into a big mass of metal...the individual laminations are still insulated from each other...and this still helps reduce the heating effect of eddy currents.

anyhow.... you can stop the buzzing by tightening or loosening screws.... it might not work every time but if I were to replace every transformer I came upon that was buzzing loudly I'd be replacing a lot of transformers...lol
and for no reason....

You can also tighten or loosen the bolts holding the laminations together if the transformer is contructed that way and I have on occasion "smacked" the corners before with the back of a screwdriver...

I guess if you make a commission off replacing parts then replacing buzzing transformers is a good thing, I guess ~:>... I dont get a commission off of parts I sell... and even when I did I still couldnt bring myself to do it....just seems unethical to me.

[deme]

Originally posted by corny
Ive silenced many many transformers since the early 80s by either tightening or loosening the mounting screws.

In 20 plus years Ive never replaced a transformer that died because of its design....its always been either because of human error or wiring problems.... Transformers just dont go bad..... Im sure a few might make it thru the factory with some defect and Im sure many die because of heat deteriorating the insulation but this heat is most likely caused by overoading the transformer.... some human putting too much of a load on it...

As far as loose laminations... thats a common problem but its pretty much a noise problem only.... those laminations are usually held together by an insulator such as varnish or lacquer and occasionally some laminations may break loose and cause hum but this does not affect the operation of the transformer to the point where heat is generated..... You want to generate heat...take a transformer apart and sand off the insulating film then put it back together...lol
it will get hot fast because you then basically have one large mass of metal for a core....

...But some transformers are bolted together or welded you jackass....

when you see a transformer bolted together or welded together on the corners...it doesnt really make the laminations into a big mass of metal...the individual laminations are still insulated from each other...and this still helps reduce the heating effect of eddy currents.

anyhow.... you can stop the buzzing by tightening or loosening screws.... it might not work every time but if I were to replace every transformer I came upon that was buzzing loudly I'd be replacing a lot of transformers...lol
and for no reason....

You can also tighten or loosen the bolts holding the laminations together if the transformer is contructed that way and I have on occasion "smacked" the corners before with the back of a screwdriver...

I guess if you make a commission off replacing parts then replacing buzzing transformers is a good thing, I guess ~:>... I dont get a commission off of parts I sell... and even when I did I still couldnt bring myself to do it....just seems unethical to me.

Right On.

[tjfreemanjr]

Thanks for the input, Corny! It sounds like you have quite a bit of experience "tweaking" tranformers to stop the vibrations. You have given me something I can try BEFORE I call out the tech this week... many thanks! I will try to get to this early this week, but I just stacked a bunch of Christmas boxes between the door and the furnace... LOL; I will have to move them to get to the transformer.

Thanks again for your help!!

[hvaclover]

[QUOTE]Originally posted by deme
[B][QUOTE]Originally posted by corny
[B]Ive silenced many many transformers since the early 80s by either tightening or loosening the mounting screws.

------------------------------------------------------------
My point is you can't silence ALL transformers by tightening screws.

Some have foot mounting (probably the most common)with the lamination spot welded to it. If these hum then the vibration is carried by contact to metal surface it's mounted to.

Yeah, you can deaden the noise TEMPORARILY by tightening them, but the harmonics are still present and that can cause the screws to back out of the threads. Maybe not today or even a month from now, but it does happen.

I/we have been replacing transformers since the seventies.

Why leave a customer with a noisy xfrmer in the first place?

Most of these are warranty issues after an installation.
If it's noisy replace it and make the customer happy.
And for what it's worth, by the time you get done tightening screws and giving your customer a bill for labor on out of warranty repairs, for a small addtional amount you can provide the customer with a new xfrmer.

I think changing the transformer is the right thing to do for your customer. That's the way we do it.

[corny]

I would give them the option.... of course...but when faced with this problem before I have always just told them exactly what I was doing....never had anyone request the transformer be changed.... I cant ever recall charging a customer for this either....

to each his own...

[riderman]

HVACLOVER

I do not disagree with your responce to to corney, But you stated:

Yeah, you can deaden the noise TEMPORARILY by tightening them, but the harmonics are still present and that can cause the screws to back out of the threads. Maybe not today or even a month from now, but it does happen

Can you please explain this statement? (the harmonics causing the screws to back out, specifically)