Electrical help pls: does cold mess w/ CB’s

Does cold weather mess with home circuit breakers?

For about 10 days now, the Midwest here has been hit by waves of cold fronts. My circuit-breaker panel is mounted on an outside wall of my garage. The snow and ice has disabled my garage-door opener, so I am manually shutting the garage door, having to leave a gap at the bottom that leaks in a lot of cold.

This morning, it is 12-F outside, and about 20-F in my garage. That’s how it’s been. During this cold snap, my garage temp has only been a little above outside temp the whole time. In 8 years living in my house, the garage has probably never before fallen been below freezing. This winter, probably for about 10 days in a row to date.

Since this cold snap started (and my garage has been a virtual ice box), my gas oven has tripped its breaker twice, and my microwave did so this morning (separate breakers).

Does cold depress the amp sensitivity of (or otherwise affect) circuit breakers, or else do I have a completely different set of problems?

A quick online search seems to suggest breakers exceed their current rating at low temp.

Originally Posted by fly135

A quick online search seems to suggest breakers exceed their current rating at low temp.

I don't think this is right. Cold temps shouldn't directly effect the capabilities of your circuit breakers. However, you said your garage has always been above freezing. Chances are your CBs had some sort of moisture built up inside and froze when the garage temp dropped below freezing. Ice expands...blah blah blah you know the rest. I'd have it checked out by an electrician or someone who knows what they're doing if you don't. CB panels aren't something to be messed around with. Hope ya find the problem!

All I can say is I found some temp vs rating curves for a particular brand that showed higher current capacity than the rated values at low temperatures. YMMV

Tomorrow I meet with the garage door repairman. First things first. Weather just continues to blast cold and more cold here.

But the weekend warms up and, with the garage door fixed, I’ll just watch the breakers. I have no good justification that the cold caused the intermittent breaker problem other than, coincidence.

Maybe this is proof of something else, that $hit happens in waves. Thanks for help.

John Bay.

Originally Posted by fly135

All I can say is I found some temp vs rating curves for a particular brand that showed higher current capacity than the rated values at low temperatures. YMMV

Hmm odd, I've never heard of temps really affecting current capacity enough to trip a breaker. Do you still have the link you saw those on? Not trying to disprove you, as you could be right. I'm just genuinely curious about it.

Now that I think about it, my neighbors have a pool, and there's a backbone run of high voltage power-lines going by their house (we live two miles from a coal-burning power plant), and when it hits 100 degrees and is humid, the electricity actually travels through the humid air. If you're in the pool and put both hands on the wet concrete to push yourself out of the pool, you can feel the current run through your body....it feels like both of your arms fell asleep. So it could possibly be more humidity related, who knows

I couldn't find the same brand/datasheet as before, but here's another one that popped up on a google search...

http://download.siliconexpert.com/pd...2_w28_0706.pdf

Check the ambient compensation chart. It handles 20% more current at freezing.

John is correct - temperature will affect the trip point of a circuit breaker, but colder temperatures would increase the trip point of the breaker. Most breakers are calibrated at 40 degree C (104 F).

Does the breaker trip right when you turn the microwave on? A gas oven wouldn't be pulling any real load, so that breaker is tripping on a short circuit. I would talk to an electrician and replace the breakers and have them check for moisture at the panel and outlets

Here we go. An expert told me that, a healthy garage-door opener shouldn’t have this.

One cue (w/o prompting by me), the repairman said, “Your stripped gear is a casualty of the cold. I replaced two of these in all of between March and November. Now, about six a week.”

Low last night, -5-F.

Gas ovens nowadays aren’t what you might commonly think. Mine’s a Whirlpool Super Capacity 465 Super Cleaning Oven (circa 2002).

It went dead after about 3 years, and I had to call a repairman then too. He opened some compartment and, to my disbelief, pulled out a virtual mother board.

I mean, it was like we had opened up the tower of a PC.

I asked, why is so much computing power needed for a gas oven? But I tuned out and didn’t listen.

I’m sure I don’t need that kind of control accuracy in a gas oven. I mean, it’s not like I’m Bobby Flay, who probably has people pouring over the user manual until late at night.