Condensation in residential breaker panel...

[siegrisd]

Hi, everyone,

Please forgive the newbie question, but, this one really has my dad and I stumped. He is an electrical contractor with 42 years of experience, so, he is the one who will be performing any tasks. Thanks for your understanding.

Here's my question:

I live in a relatively new home (about 4 years old). My panel and meter are located on the south side exterior of the house. Whenever there is a sharp increase in humidity coupled with a decrease in temperature, a huge amount of condensation develops in the panel. The panel is made by Siemens and appears to be an outdoor-rated panel. I discovered the condensation problem when the AFCIs on the bedroom circuits were tripping. I'd go to reset the breakers and they'd continue to trip. I then discovered that the inside of the door and the bottom of the panel itself was covered with water. I went ahead and pulled the inner cover off to see where the condensation was coming from. I couldn't find any obvious sources. I did, however, pull out one of the AFCIs. About a quarter teaspoon of water poured out if it. My father came by and replaced it, however, he couldn't find the source of the condensation either.

The house is on very sandy soils, so, we thought that moisture might have been coming up through the conduit for the service (service is buried). So, I injected the conduit between the meter base and the panel with expanding foam insulation and added thick, foam tape-type weather stripping to the door of the panel to try to keep it dry inside. Neither of these solutions have worked.

Other than the obvious safety issue that this creates, I'm getting pretty tired of having to wait for the AFCIs to dry out before I can reset the breakers.

Have any of you heard of this and is there a real solution??

Thanks so much for your help.

 

[Dennis Alwon]

I have seen this problem often and I am not sure there is a solution. First off I would check to see where the wires come into the panel. If they are coming from a crawl space into the back of the panel through a 2" nipple then I would try to stuff some insulation in the openings of the nipple where all the wires ente the panel.

The cool air either from the house or the crawl space is meeting the hot humid air outside and condensating.

Good luck

 

[480sparky]

You hit the nail on the head when you said it is condensation, caused by a sharp increase in humidity and temperature change. Warm, moist air is coming in contact with cool, dry air and that's causing the condensation.

Get a package of duct seal and seal off all the penetrations made by the wiring. Do this on all the wires... service, feeder and branch. Work it between and around the wires to prevent any air flow. Stop the air flowing and you'll stop the condensation.

 

[RayS]

You hit the nail on the head when you said it is condensation, caused by a sharp increase in humidity and temperature change. Warm, moist air is coming in contact with cool, dry air and that's causing the condensation.

Get a package of duct seal and seal off all the penetrations made by the wiring. Do this on all the wires... service, feeder and branch. Work it between and around the wires to prevent any air flow. Stop the air flowing and you'll stop the condensation.

yep. especially any runs going outdoors. There are also small anti-condensation heaters available, typically used in outdoor control panels, but I'd hate to see you resort to one here, given that the afci's themselves put off some heat. If sealing alone doesn't do it, I'd try to add an empty conduit hi and low for venting, both ending somewhere dry

 

[realolman]

I like RayS's empty conduit idea. I think insulation from the outside and ventilation to the inside would be better than sealing. I assume your living space is not all that humid.

If your dad's a contractor, get him to move it. I don't get that outside breaker panel stuff anyway. I live in Pennsylvania. I've never seen one outside. Why would it be located outside?

 

[brian john]

Did you say the Muffin Man on Drury lane, NO I SAID A MUFFIN FAN, vent the panel with a Radio Shack muffin fan.

 

[Dennis Alwon]

I don't get that outside breaker panel stuff anyway. I live in Pennsylvania. I've never seen one outside. Why would it be located outside?

No basements in many of the homes around here so no good place to put a panel unless you want it in the middle of a bedroom or living room.

I agree they are not the best idea but sometimes the HO gives us no choice. Most of the homes I work on now have garages and basements so it's not an issue but the smaller homes usually don't have either.

 

[Pierre C Belarge]

You hit the nail on the head when you said it is condensation, caused by a sharp increase in humidity and temperature change. Warm, moist air is coming in contact with cool, dry air and that's causing the condensation.

Get a package of duct seal and seal off all the penetrations made by the wiring. Do this on all the wires... service, feeder and branch. Work it between and around the wires to prevent any air flow. Stop the air flowing and you'll stop the condensation.

This is most likely the way to solve your issue. It is also a very cost effective way to solve the issue. I would be willing to bet 480sparky's money that it works. If you should choose to do this, let us know if it is effective in reducing if not stopping the moisture issue.

Also:
If those breakers have had enough moisture in them over the years (4), I would replace them after you solve this issue.

 

[benmin]

You hit the nail on the head when you said it is condensation, caused by a sharp increase in humidity and temperature change. Warm, moist air is coming in contact with cool, dry air and that's causing the condensation.

Get a package of duct seal and seal off all the penetrations made by the wiring. Do this on all the wires... service, feeder and branch. Work it between and around the wires to prevent any air flow. Stop the air flowing and you'll stop the condensation.

This is most likely the way to solve your issue. It is also a very cost effective way to solve the issue. I would be willing to bet 480sparky's money that it works. If you should choose to do this, let us know if it is effective in reducing if not stopping the moisture issue.

Also:
If those breakers have had enough moisture in them over the years (4), I would replace them after you solve this issue.

I agree with this fix.

I've also seen the problem in reverse. Warm moist air coming from a conduit from the panel to an outdoor automatic transfer switch for a generator. Caused ice to form on the electronics and then failure. Was cured by the same method

 

[480sparky]

I would be willing to bet 480sparky's money that it works.

You're assuming I have money?

 

[siegrisd]

Thanks, everyone!

Thanks, everyone!

Thanks for all of the responses!

I've actually done a lot of the recommended solutions:

I've insulated the nipple from the panel into the house, the nipple from the meter base to the panel, added, insulation around the outer panel door, and sealed any knock outs and perforations in the panel box itself. I'm still getting condensation build-up.

I suppose that the reverse is now possible - namely venting the panel in some way. I like the fan idea, but, there's still a lot of new construction in my area and, thus, a LOT of blowing sand and dust. I'm concerned about building up a lot of debris in the panel, too.

Any other ideas? Thanks, again!

 

[dwellselectric]

Get a dehumidifier and plug it in the panel outlet. Bet you wont get anymore water

 

[480sparky]

It's been less than 24 hours. You may have moisture that is still working it's way down from where it was. Give it a little more time and see what happens.

 

[cowboyjwc]

Just make sure that you are using duct seal or silicone and not that expandable spray foam.

 

[aja21]

I agree with this fix.

I've also seen the problem in reverse. Warm moist air coming from a conduit from the panel to an outdoor automatic transfer switch for a generator. Caused ice to form on the electronics and then failure. Was cured by the same method

Been there done that a lot. Works every time, almost.

 

[JohnJ0906]

Also:
If those breakers have had enough moisture in them over the years (4), I would replace them after you solve this issue.

I think this is a good idea. After you solve this problem, I would replace all the breakers. I just wouldn't trust any of them if there has been that much moisture over 4 years.

 

[480sparky]

Take a good look at the bus bars when all the breakers are out. I've seen moisture like this create a lot of corrosion on them as well.

 

[LawnGuyLandSparky]

Install a drain and a bottle, that's FREE pure distilled water, perfect for the humidor!