Walk-In Coolers

[augie47]

What type of wiring methods do you normally install/accept in walk-in coolers & freezers (Restaurant/grocery facilities) ?
The majority I see are wired with EMT, but I see a mix of compression and set-screw fittings, standard boxes and bell boxes, etc.

 

[A/A Fuel GTX]

I typically treat walk in coolers/freezers as wet locations and use appropriate wiring methods.

 

[K8MHZ]

I typically treat walk in coolers/freezers as wet locations and use appropriate wiring methods.

Like THWN inside FMC?

 

[K8MHZ]

Damp vs. wet.

This was brought up during an inspection meeting at a store we were working on. What it came down to was that in any cooler where there was a wet wash down, it was treated as a wet location. If not, it could be considered a damp location.

As it was, all the coolers had to be considered wet.

Plans called for THWN inside FMC. Inspector didn't like it but said it was not an NEC violation. I didn't like it either and got the method changed to EMT, compression and seal-tite.

This is one of those things that illustrate that the NEC is a minimum standard, not necessarily an acceptable one.

 

[iwire]

If you think about any factory made equipment for inside these coolers none of it is more than dry location.

Personnel I find bell boxes do more harm then good.

 

[iwire]

I didn't like it either and got the method changed to EMT, compression and seal-tite.

Just asking for trouble ............

 

[John120/240]

If you think about any factory made equipment for inside these coolers none of it is more than dry location.

Personnel I find bell boxes do more harm then good.

Iwire what is the objection to bell boxes ?

 

[K8MHZ]

If you think about any factory made equipment for inside these coolers none of it is more than dry location.

Personnel I find bell boxes do more harm then good.

I agree. They are water / insect / spider attractant by design.

 

[K8MHZ]

Just asking for trouble ............

What would your choice have been?

 

[iwire]

Iwire what is the objection to bell boxes ?

Keep in mind that for the past 15 or years or so I have done Supermarket construction and maintenance.

More often then bell boxes just give a place for water to collect in.

Lets look at this the other direction, how many of you have seen a failure of the wiring method when dry location methods are used in coolers and freezers. (Unless the area is subject to wash down)

About a year ago we installed doors on about 60 dairy coolers, they used to be the open type.

The doors and frames were made by http://www.anthonyintl.com/en/Index.aspx and each had anti-sweat heaters and lighting. So the factory left 1/2" FMC whips hanging out of each frame (2 to 5 doors per frame) for us to connect to.

I have done prefab coolers for 7-11s, all the factory wiring was FMC.

I really can't think of a reason to use wet location metods unless the area is subject to wash down.

 

[iwire]

What would your choice have been?

EMT, set screw fittings and FMC just like the factories that make the equipment use.

 

[iwire]

Here is a shot of the doors I was taking about, the FMC whips are factory.

It happens I used bell boxes and compression here because I was buying stock for a number of crews and some of the guys were complaining that it had to be wet location methods so I just caved in and went with it. But it seems pretty damn foolish to run FMC into a bell box.

 

[John120/240]

Having worked in a grocery store 15 years ago, after seeing Iwire's picture EMT would be

acceptable. The FMC makes the bell boxes overkill.

 

[John120/240]

Bob do you take pictures of all of your installations ? I can see where it is easier to show the

new guy " I want it done like this"

 

[norcal]

When doing a walk-in learned real quick that conduits going through the walls need to be sealed. Nothing like coming back to them & finding lighting fixtures full of water.

 

[guschash]

I don't consider that a walk-in cooler. I think EMT , FS boxes is what I used in my boy's pizzas stores, for the walk-in coolers. There are a lot of different sizes of walk-in coolers. I don't think of his coolers as being wet location so much as a damp location. They might wash the walls but not to point of that I would consider calling it a wet location. But then again I been wrong before but enjoy learning how wrong I am.

 

[renosteinke]

Not all coolers are created alike! Here's a classic case of where you need to know more than the NEC. Mainly, you need to be on the same page as the Health inspector.

First, you have a basic design choice to make: wiring inside the cooler, or outside. On balance, you're usually best served by having as little inside the cooler as possible; just be sure to seal your penetrations thoroughly, on both sides of the wall.

You'll need penetrations for the light, the refrigeration equipment, and -maybe- the thermostat.

Inside the cooler you have two issues: clearance and cleaning.

Clearance: Anything in the cooler will interfere with moving stock around. Your mounting hardware can also damage the product. Try to run your stuff up high.

Cleaning: Depending on what the cooler is for, you may be required to stand everything off the walls for cleaning. The Health guy might accept mineralacs, or you might need to get some 1-1/2" plastic stand-offs from a plumbing house.

I use Bell boxes, and mount them flat to the cooler. Depending on the cooler, I might just use ordinary stainless cover plates, or I might use weatherproof ones.

It's not just about the Bell boxes being 'waterproof.' Rather, it's about the boxes having a nice, smooth outside that won't collect crud over time.

If you can, place your GFCI's and switches outside the cooler. I try to have some sort of visual indication that the light is on inside the cooler- a 'pilot light' switch can serve.

I always use compression connectors, though not the special 'rain tight' ones. Again, it's more because I don't want the set screw heads tearing up the product.

 

[kwired]

If you think about any factory made equipment for inside these coolers none of it is more than dry location.

Personnel I find bell boxes do more harm then good.

More often then bell boxes just give a place for water to collect in.

Lets look at this the other direction, how many of you have seen a failure of the wiring method when dry location methods are used in coolers and freezers. (Unless the area is subject to wash down)
..
I really can't think of a reason to use wet location metods unless the area is subject to wash down.

I can't possibly agree at any higher level.

renosteinke, said most of what I think also, every cooler is different.

Unless washdown is a routine thing this is a most a damp location.

Chilled air is going to be dry air. If the door is opened a lot, you let warmer higher humidity air inside and will get condensation as a result. If the cooler is not opened to moist air very often condensation will be minimal and you have a pretty dry location outside of any washing.

Bell boxes as Iwire says are good at collecting water. What keeps water out also keeps it in. I have not done a lot of coolers, I have done many grain storage bins over the years. Seen many bell boxes filled with water. Arrangement to drain is important in condensing environments. Drilling weep holes is a good practice especially in bell boxes - even if there is a raceway entry in the bottom. The opening into the bottom raceway is usually higher than the lower device mounting screw and it will still fill up with water above that screw and it will sieze up and not be able to be removed - seen that happen hundreds or even thousands of times.

I have also done work in dairy foods processing facility, where washing everything imaginable can be done several times a day. Anything that keeps water out will also keep it in if it does find a way in. Designing to drain is important.

 

[jap]

I can't possibly agree at any higher level.


Bell boxes as Iwire says are good at collecting water. What keeps water out also keeps it in. I have not done a lot of coolers, I have done many grain storage bins over the years. Seen many bell boxes filled with water. Arrangement to drain is important in condensing environments. Drilling weep holes is a good practice especially in bell boxes - even if there is a raceway entry in the bottom. The opening into the bottom raceway is usually higher than the lower device mounting screw and it will still fill up with water above that screw and it will sieze up and not be able to be removed - seen that happen hundreds or even thousands of times.

I drill weep holes in the bottom of Bell boxes also. I cant count the number of Bottom screws I've broke off because of rust seizing the bottom screw. They really ought to make Bell Boxes with Nylon Mounting Straps on top and bottom. The metal screw on the metal strap always rust and I'm not a big fan of nylon screws.

 

[kwired]

I can't possibly agree at any higher level.


Bell boxes as Iwire says are good at collecting water. What keeps water out also keeps it in. I have not done a lot of coolers, I have done many grain storage bins over the years. Seen many bell boxes filled with water. Arrangement to drain is important in condensing environments. Drilling weep holes is a good practice especially in bell boxes - even if there is a raceway entry in the bottom. The opening into the bottom raceway is usually higher than the lower device mounting screw and it will still fill up with water above that screw and it will sieze up and not be able to be removed - seen that happen hundreds or even thousands of times.

I drill weep holes in the bottom of Bell boxes also. I cant count the number of Bottom screws I've broke off because of rust seizing the bottom screw. They really ought to make Bell Boxes with Nylon Mounting Straps on top and bottom. The metal screw on the metal strap always rust and I'm not a big fan of nylon screws.

I don't think it would help much, seen same screw in similar situation rust, sieze up, and end up twisting off when trying to remove it in PVC FS boxes also, they too need provisions to drain.