Ever seen an Electrical panel inside of a walk in freezer??

[jbgoosehunter]

At my work there has been a 208 V 3 phase 225 amp panel installed in a commercial walk in freezer. Over the years there has been some water damage from the freezer being defrosted however the panel still works. It just seems like an odd place for an electrical panel. The panel is just a standard QO style square d panel. Its not weather proof and has eccentric ko's in the top of it. The tempreture is kept between 0 and 28 degrees F. in the freezer but ocasionally they defrost it. The freezer typically has frost on the walls. We are in the process of remodeling the freezer and I'd like to re-locate the panel outside of the freezer. I just need some code back-up to convince the boss that it is the thing to do. I cant find any specific info in the code related to a panel in a freezer. Ive only found stuff about the panel needing to be weather proof rated for a wet location. Has anyone ever seen this before and what are your thoughts? Please respond to [Moderator's note: email address removed. Use private message to initiate contact.]

 

[Ponchik]

I don't think the freezer is considered a wet location. Even though it is cold, but generally it stay dry. The best is relocate it outside. You can also build an enclosure around it.

where is the defrost water entering from?

Also something that i would be concerned about is, if the breakers are in that cold environment
and if subject to an overload, will they open in a timely fashion? Do breakers have to be rated for a cold environment?

 

[LEO2854]

At my work there has been a 208 V 3 phase 225 amp panel installed in a commercial walk in freezer. Over the years there has been some water damage from the freezer being defrosted however the panel still works. It just seems like an odd place for an electrical panel. The panel is just a standard QO style square d panel. Its not weather proof and has eccentric ko's in the top of it. The tempreture is kept between 0 and 28 degrees F. in the freezer but ocasionally they defrost it. The freezer typically has frost on the walls. We are in the process of remodeling the freezer and I'd like to re-locate the panel outside of the freezer. I just need some code back-up to convince the boss that it is the thing to do. I cant find any specific info in the code related to a panel in a freezer. Ive only found stuff about the panel needing to be weather proof rated for a wet location. Has anyone ever seen this before and what are your thoughts? Please respond to jbgoosehunter@gmail.com

If the electrical panel has water damage then it should be replaced.

This is from NEMA....http://www.eatoncanada.ca/downloads/guidelines_handling_water_damaged_elect_equip1.pdf

 

[jim dungar]

Also something that i would be concerned about is, if the breakers are in that cold environment
and if subject to an overload, will they open in a timely fashion? Do breakers have to be rated for a cold environment?

The breakers will take longer to operate on overcurrents but the conductors can also handle more current, so the two items are usually considered to cancel each other and no re-rating is applied.

There are often re-rating factors for breakers and conductors, which must be considered whenever ambients are outside the range of 20-40?C (68-104?F). Also, there will be different considerations when the device is in a different ambient than the equipment it protects.

 

[ghorwood]

Electrical panel vs freezer

Electrical panel vs freezer

I could never find the inside of a freezer or cooler to be defined as a wet location in the NEC. The closest it comes is to state that "...some cold storage warehouses..." are damp locations. However, the NEC is a minimum.
I would always consider such locations to be damp, at least, wet is better. A lot of times the interior is hosed down periodically, plus there is forever condensation forming in them if everything is not 100% sealed off. That includes inside and outside every conduit penetration through the exterior walls/ceilings. Any place where there is a difference in temperature from inside the box to outside. Many such places require seal-offs at the penetrations, both inside and outside, as a thermal barrier. You should leave no more than 1/8" gap between the exterior wall/ceiling panels and the conduit. Caulk around it with silicone. (It is helpful to use a caulk colored the same as the wall panels, so it's easier to see if you missed one. Clear caulk will drive you crazy in this case.) After wiring is pulled, shoot caulk inside the conduit, where it penetrates the wall/ceiling panel, around the wires. Fill the pipe. The code allows the seal-offs to be used in this manner. I have also used condulets and j-boxes for this purpose with excellent results. A good caulking job may cure most of the condensation problem.
I would replace that panel with a 3R model. Remember to also seal the conduits entering/exiting the panel. The breakers will operate just fine.

 

[jim dungar]

I would replace that panel with a 3R model. Remember to also seal the conduits entering/exiting the panel. The breakers will operate just fine.

In my experience the breakers will rust and fail at about the same rate as the steel in the panel, regardless if it is 3R rated.
The biggest moisture problem will often be the condensation that forms inside of the breakers and panels as they are warmed during the defrost cycle.

 

[growler]

We are in the process of remodeling the freezer and I'd like to re-locate the panel outside of the freezer. I just need some code back-up to convince the boss that it is the thing to do. I cant find any specific info in the code related to a panel in a freezer.

You really can't use the code book as a design manual. I think it's a dumb idea to put the panel in a walk-in freezer but if there is working clearance there probably isn't a specific rule agaist it (can't think of one).


I think it would be a lot better to mount the panel on the outside and use seals on all conduit entering the panel to seperate hot and cold air and eliminate condensation. Keeping the breakers and bus high and dry should make everything last a lot longer and that's usually a consideration.

 

[ggunn]

In my experience the breakers will rust and fail at about the same rate as the steel in the panel, regardless if it is 3R rated.
The biggest moisture problem will often be the condensation that forms inside of the breakers and panels as they are warmed during the defrost cycle.

Condensation happens when things are cooled.

 

[jim dungar]

Condensation happens when things are cooled.

Tell that to my garage floor when the ground thaws every spring.

Condensation happens when humid air meets cooler air.

During defrost, the warm moist ambient air will make contact with the cold air inside the panel and the inside the breakers.

 

[masterinbama]

Whenever I have a large amount of circuits entering a commercial cooler or freezer I set 2 wireways below the bottom edge of the panel. One inside nippled through the freezer wall to one outside and then nippled up to the bottom of the panel. That way even if your conduits aren't sealed completely, any condensation will drain away from the panel rather than into it.

 

[RonR]

I have never saw a panel in a freezer but I have seen one under a kitchen Sink.

 

[texie]

Whenever I have a large amount of circuits entering a commercial cooler or freezer I set 2 wireways below the bottom edge of the panel. One inside nippled through the freezer wall to one outside and then nippled up to the bottom of the panel. That way even if your conduits aren't sealed completely, any condensation will drain away from the panel rather than into it.

Sounds like a good practice. For the OP, I don't think you will find any NEC violation with the panel inside the cooler/freezer. Is it a good idea or practice? I think not.

 

[ActionDave]

Sounds like a good practice. For the OP, I don't think you will find any NEC violation with the panel inside the cooler/freezer. Is it a good idea or practice? I think not.

Where I live it is very dry so condensation is not an issue. I don't see panels in walk ins every day but I have seen a few and they are in good shape. It would seem to me to be no worse a location than an outdoor panel in the upper Midwest during winter.

 

[hurk27]

In Florida it is common to have the panel outside, and I have seen my share of R-3 panels rotted out just from the condensation or a sprinkler system spraying up at it as they didn't think about air flow and didn't seal the conduits, air conditioning is not as much of a problem as they remove the moisture in most cases but in the winter the warm air in the house flowing to the outside tends to cause allot of moisture in these panels.

But what I question is even an R-3 panel will not protect from someone spraying water at a panel as they are only design to be rain tight not water proof, a few years back we had to replace a panel in a walk in cooler but we put a wire way with a seal on the cover to pick up all the conduits and used a 2" conduit through the back of it into the new panel on the other side of the wall to which we sealed on both sides and being shorter then 24" no derating was required, also the main reason we had to replace the panel was it was an ITE with a aluminum bus that kept corroding and causing breakers to fail, while there were extra spaces that they had move replacement breakers to, they eventually ran out of good spaces as the bus had burned on the breaker stabs, so using copper bus panels is a must when moisture is a problem.

 

[kwired]

Sounds like a good practice. For the OP, I don't think you will find any NEC violation with the panel inside the cooler/freezer. Is it a good idea or practice? I think not.

Smaller coolers/freezers may present 110.26 issues, usually the space inside is valuable space. But a large refrigerated warehouse may very well have all kinds of electrical equipment installed within and is not necessarily a wet or damp location either. Cold air holds less moisture. Only reason for condensation is when someone lets in warmer air. A large warehouse will only have this problem near entrances.