Suggestions for weather proof devices in walk in freezers

neko988

Member
Hey guys, how is everyone else dealing with condensation issues with devices (a/v mostly) being installed into walkin freezers? Seems no matter what set up we use, we run into repeat issues. With the hot and humid weather coming back, it's that time again. I've seen where EMT was sealed above the freezer with silicone in the warm zone as well as at the back box in the cold zone. All devices are always weather proof with same manufacturers back boxes. This instance is in a area that isn't a space with wash downs. Would love to hear any suggestions, thanks in advance ....
 

iwire

Moderator
Staff member
Location
Massachusetts
If the conduit is not sealed well there are no devices that will last. Sealing the conduit is also directly required by the NEC.

About 15 years of supermarket experience here and have gone on plenty of service calls for that.

As far as a wash down area any normal weather resistant units should work fine.
 

mopowr steve

Senior Member
Location
NW Ohio
I have heard of someone using explosion proof fitting at the cold/warm division. Would think that seals excellent if done properly.
Silicone may or maynot be sealing completely?
 

cadpoint

Senior Member
Location
Durham, NC
You might consider PVC 5"-6" through the roof these will not hold down the temperture and
not let other mating materials cool down and help condensations, You might also consider raising the boxes off the roof onto rubberized strut.

You can get the threaded pipe fittings in the lawn and garden section.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
If the area is not a wash down area, I would not be using weatherproof boxes, all they do in this application is trap water inside the box and make the problem worse. NEMA 1 boxes will let the condensed water drain out and work better than a weatherproof box. Of course when you have a wash down area, you have to use wet location boxes.
 

neko988

Member
An explosion proof fitting by itself has no sealing function. An explosion proof seal-off(?) would be a different matter.[/QUOT.

Sorry but yes a seal-off fitting with filler and Chico


Not having done any explosion proof installs before, I just did some reading on the seal offs and Chico. We will start to swap problem areas out a few at a time when the issue returns and see if this is the saving grace I have been looking for. Thanks for all the help guys.
 

neko988

Member
I've seen so many different installs, some PVC, EMT and rigid, all seem to suffer failures pretty regularly. Latest example was walk in freezer, wheelock w/p h/s with w/p back box. All rigid, less then 3 feet from device with 2 sweeps, no couplings with a vertical stub up into a hallway above. Silicone at the box in the warm zone (about 2 feet above freezer) and silicone at box entrance in freezer. Device is mounted to a concrete wall within the freezer. No wash downs in this area, 2 1/8th inch weep holes in bottom of box. All installed approx 8 months ago. Device had so much corrosion and the amount of water in the box was pretty substantial.
 

mopowr steve

Senior Member
Location
NW Ohio
Huge waste of money in my opinion.

It is not required and not needed.
Although I may agree on cost have you ever witnessed the execution of this method and whether it WORKED ? To keep the moisture from air in conduits from the exterior of a refrigeration unit from condensating within, at the cold/warm division.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
All I can say is if the conduit is sealed with a waterproof seal above the box in the cold zone I would expect to find the conduit filled with water and none in the box. So the problem can only be either of two things- the seal you installed isn't watertight like you thought or the condensation is being generated within the walk-in box and has nothing to do with what you are thinking.

-Hal
 
Top