"Hum" Coming from Electrical Panel

[mensa]

Yesterday, our garage door went up by itself. I checked to make sure that the opener buttons were not pressed in. I then went downstairs and heard the buzz or hum at the panel. Thinking that the meter or the stack might have an ice buildup, I went outside to check them, but all seemed dry and normal.

This morning, our furnace failed to kick in when the thermostat timer called for an increase in temperature. Tried resetting the thermostat to no avail. Knowing that there had been some kind of weirdness at the panel yesterday, I went down and turned the breakers off and on one by one. Lo and behold, the furnace came on.

Obviously, I suspect that the garage door phantom and the furnace failure stem from something going on at the panel...but what could it be? Anyone got an idea or a troubleshooting checklist?

[ratrationale]

I couldn't tell you what caused these issues, but typically when a furnace doesn't kick in you can check if there are blinking lights at the furnace panel and compare the scenario with the furnace manual.

As for a humming sound at the electrical panel, this happened to me once, it was the power converter for the door bell which was making a loud buzzing sound, could that be it? A little slap had fixed the buzzing sound...

[DaveSch]

It could be that you have a failing circuit breaker. You should talk with someone that is comfortable with opening a panel and replacing a breaker. Write down the name of the manufacturer of the panel, and the current rating (amps) of the breaker in question. Each panel manufacturer uses a different style breaker and they aren't interchangeable between manufacturers.  Then go to your local home improvement store and buy one. Always good to have a spare anyway. Circuit breakers are easy to change, but should only be done by someone that won't get hurt. Use Google to find information on this subject.

Dave

[mensa]

Thanks for the replies.

Dave, would the fact that my house is wired in low voltage make a difference in any way to your suggestion? I know that I can't get replacement parts easily for the wiring, but I wouldn't think that that would make a difference in the panel...but I obviously have no clue :-/

[DaveSch]

Hi,
The low voltage in your house is just for control. The actual lights and appliances run on 120/240 volts ac. You still have a circuit breaker panel. The low voltage control is probably mostly for your lighting, with a electromagnetic relay at each light fixture. That is not the problem.

The circuit breakers have electromagnetic coils that can cause humming and buzzing if the breakers are heading for the last roundup. The fact that you were able to get your furnace to work again by flipping the breaker tells me that there *could* be a problem. It would be better to have a spare in case a breaker to your furnace went bad (in the cold winter). Has your furnace been working since you cycled that breaker?

But don't buy any of the low voltage control relays.

Dave

[mensa]

Thanks Dave,

Yes, the furnace has been fine, and the garage door has not randomly opened again. The hum at the panel is still present, however. I will search out a spare circuit breaker, but I'll certainly be calling someone who knows what s/he's doing to change it, if necessary!

[Greg]

Garage door opener remotes operate on fairly common frequencies... some car alarms operate in the same range.
 It could have been a neighbor or other source of radio interference that caused it to open.  An electrical fault in the panel is unlikely to cause the door to operate.

[Vilx-]

A source of hum that I've experienced myself is electrical sparks at wire couplings (sorry if that's not the correct term). Basically there are places where 2 wires are connected together somehow. If moisture gets in there, it could cause corrosion of the wires to the point where they don't touch directly anymore (flow of current accelerates the corrosion by an order of magnitude. I think it was called "electrolysis", though I'm not sure). However there's some nearby spot where the wires are so close that electricity can jump the gap, so it keeps doing that (producing sparks) - which is what you hear. In this case, kicking the box would likely quiet it down, because the wires would jiggle a bit and touch directly again. Also, such an indirect contact would have a pretty high resistance, which means that your devices would have an unstable power supply (or simply insufficient). That can cause all kinds of odd side effects.

Anyways, if this is the case, you'd better find that place and eliminate it quickly. Sparks generate lots of heat. If you're unlucky enough, they could even start a fire. You should be able to identify the faulty place quickly by the rust and burn marks.