# Walk-in Refrigerator , install New



## telsa (May 22, 2015)

I can scarcely READ your OP.

Break it down.

Thanks.


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## ggratecc (Mar 25, 2008)

I wish I could add an image to this post, but will break down the specs differently:
POWER
SUPPLY 
Volts / Ph / Hz
208-230/1/60

COMPRESSOR 1 HP
RLA LRA
6.3 34.2

FAN MOTOR
QTY HP FLA
1 1/15 0.5


MCA†
Air Elec.
15 20 

MOP‡
Air Elec.
15 20

Evap.Fan
Amps
7

Defrost Heater
Amps
15

†MCA=Minimum Circuit Ampacity
‡MOP = Maximum OvercurrentProtection


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## backstay (Feb 3, 2011)

6.3 amps would be compressor, 
.5 amps evap fan
You would have a lighting circuit( 15 amps )
Heaters around the door ( 20 amps )
No defrost because its a fridge, I stand corrected. 

You treat the motors as 1.25 % of the largest and 100 % of the smaller, then the lights and heaters are figured as their real load not 15 and 20. I would run one circuit for motors and one or two for the rest. Are the heaters 120 or 240? The motors get a bigger breaker so they will start, so that's why I'd separate them. I don't like mixed loads on my motors anyway.

I find it odd the evap fan is bigger than the compressor.


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## ggratecc (Mar 25, 2008)

There is no mention of 120v loads, so I presume the heaters are 240v.
This is a 10' x 10' x 8' unit.
Spec sheet says it comes standard with a "large electrical panel".

I'm still trying to get the big picture of what I need at the unit...do I need a 30A fused disconnect for the unit? Then a second circuit for lighting of 15A?
thanks


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## MechanicalDVR (Dec 29, 2007)

ggratecc said:


> There is no mention of 120v loads, so I presume the heaters are 240v.
> This is a 10' x 10' x 8' unit.
> Spec sheet says it comes standard with a "large electrical panel".
> 
> ...


1 240v Circuit external of the box just for the condensing unit (compr/condenser fan) on the top of the box.

1 120v Circuit for the internal lighting.

1 240v Circuit for the evap fans and mullion heaters.

Some do use 120v evap fans it depends on the way it was ordered.

You will need to provide a disconnect for the condensing unit they do not come with them.

Don't ever recall an 'electrical panel' coming with any walk-in box.


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## sbrn33 (Mar 15, 2007)

All you care about is 
MCA for wire size and 
MCB for breaker size. 
They do all the hard work for you.


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## joebanana (Dec 21, 2010)

MOP 20a. and 15a. for the evap.
Means, 20 amp ckt. for the condenser, and a 15a. ckt. for the evaporator. (the other end)


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## ggratecc (Mar 25, 2008)

Thanks to all who have replied so far.
The spec sheet says the lighting is prewired, but I guess that it needs 120v 15A circuit as two of you mentioned.

So...it sounds like I would need to start at my panel 80 feet away from the unit, and run
1. 20A circuit for condenser/comp. Install 20A compressor disconnect at unit.
2. 15A circuit, 240v for Evaporator
3. 15A circuit, 120v for lighting.

I could run 1" conduit, partially EMT, partially PVC.
I would need to pull 7 wires!
does this sound like the way to do it? 
thanks in advance.


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## MechanicalDVR (Dec 29, 2007)

ggratecc said:


> Thanks to all who have replied so far.
> The spec sheet says the lighting is prewired, but I guess that it needs 120v 15A circuit as two of you mentioned.
> 
> So...it sounds like I would need to start at my panel 80 feet away from the unit, and run
> ...



You are going to want a 30 amp disconnect, they are typically rated 30, 60, etc.


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## ggratecc (Mar 25, 2008)

MechanicalDVR said:


> You are going to want a 30 amp disconnect, they are typically rated 30, 60, etc.


yes, thanks for that.

Now, can I run the entire conduit and 7 wires into the unit panel, and then come back out with 240v 20A circuit to the disconnect?
or
do I need to pull the 7 wires into a JB within 6ft of unit first?

so many questions... For someone who repaired all electrical equipment on a nuclear submarine I'm sounding like a rookie. 
When the unit is purchased and can get a look at it, I will draw up a diagram for all the see.


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## catsparky1 (Sep 24, 2013)

You can use a two pole motor rated switch on condenser and you will need a switch for the fans inside . You can put the lights with the fans but when it goes down you work in the dark . If has temp reading on door you will need a white at the switch and if it has that if you use solid wire you will want to kill the maker of said box YO .


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## scotch (Oct 17, 2013)

ggratecc said:


> I wish I could add an image to this post, but will break down the specs differently:
> POWER
> SUPPLY
> Volts / Ph / Hz
> ...


A 1 hp refrigeration compressor should be around 9 amps ...and evap fan will be about 1 amp....maybe it's 0.7 A . Anyway ....20A breaker sounds about right.


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## ggratecc (Mar 25, 2008)

scotch said:


> A 1 hp refrigeration compressor should be around 9 amps ...and evap fan will be about 1 amp....maybe it's 0.7 A . Anyway ....20A breaker sounds about right.


Scotch,
So if I understand you correctly I could simply pull a 20A 240v circuit as the MOP suggests, have it go through the disconnect and have it power all loads except lights.
The spec sheet never mentions the lighting load, just that it is prewired.
In conclusion, seems I am down to:
1. 20A 240v circuit for condenser/comp/evap fan.
2. 15A circuit, 120v for lighting.
5 wire pull only.
Please correct me if does not sound right for a 1 HP compressor unit.


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## MechanicalDVR (Dec 29, 2007)

catsparky1 said:


> You can use a two pole motor rated switch on condenser and you will need a switch for the fans inside . You can put the lights with the fans but when it goes down you work in the dark . If has temp reading on door you will need a white at the switch and if it has that if you use solid wire you will want to kill the maker of said box YO .


That is assuming there is a digital temperature readout and the evap fans are 120v.


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## MechanicalDVR (Dec 29, 2007)

Welcome aboard ggratecc! Enjoy your ride here.


Are you working as an electrician or an EE and someone else is doing this install??


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## telsa (May 22, 2015)

It's hard to believe, but virtually every grocer in town will let you take a peak at their existing walk-in cold boxes.

You'll get a TON of great ideas from such inspections.

&&&

OP: You omitted illumination. 

This will usually be required for even the smallest walk-in boxes.

The switch controlling such a fixture will typically have a pilot light.

For real fun, the larger boxes will feature 3-way switching with pilots at every switch position.

The light fixture will have to be rated for cold temperatures, and you should expect to see them firing up 32W T8 four-foot lamps inside a WP sealed mount. However, LEDs are now so cheap that they're ideal. 

Keep in mind that you need to seal off your penetrations as otherwise the energy loss and water condensation issues will be absurd.

It's common for the jump from the interior to the exterior to be by way of PVC. ( ~5" long ) This is choked with foam/ duct seal/ wadding.

The typical drill for raceways is EMT -- cable would be quite unusual.

Motor-rated switches are THE way you achieve your disconnecting means for every motor load. At your power level, the motors come with internal thermal overload protection that automatically re-sets. So you just never see combo-starters. 

System control us usually by way of an adjustable thermostat tucked in with the evaporating coils.

Your first time out will prove to be a slog. You have to clamber all over the box.

Any internal EMT raceways will need to be WP... with compression type WP fittings. These will have to be set off from the box so that it can be washed down, whether that ever happens or not. ( Food handling Code, etc. ) The typical device used is the ol' Minnerallac strap.

Beware that the thin metal cladding is feeble. You must stay away from the wood framing while penetrating the box. The proper technique is to anchor your boxes to the (hidden and wrapped) wood framing in such a way that you can come out of the box's back to penetrate the insulation.

You may discover that a very long 1/4" pilot bit ( bell hanger bit ) is best used to get your penetrations to line up. Then you can attack the sandwich going both ways, clean and sweet.

The whole affair is mighty labor intensive, BTW.


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## 3DDesign (Oct 25, 2014)

You haven't given a link to the entire cooler, only the compressor.
The configuration of these varies widely and depends on the unit ordered.

Some are just a box with panels that need assembled and a door installed.
These type require complete wiring of each component including supplying disconnects and installing every aspect including lighting. The compressor, evaporator fans, thermostat, defrost timer and defrost heaters, all need installed and wired. A walk-in cooler usually does not have a door heater - all walk-in freezers do. However it could have a door heater to avoid condensation.

Some come pre wired with whips that simply connect to the proper component. This type will have the lighting and switch preassembled and installed. The whip from the switch needs 120V power. Sometimes the unit will include a prewired panel with disconnects and the defrost timer ready to go. In this case, run from the panel to the compressor and evaporator fans. The heaters will be prewired and will be part of the evaporator's power requirement.

The difference in cost between the two designs is huge. Do you have a link to the entire unit?


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## MechanicalDVR (Dec 29, 2007)

3DDesign said:


> You haven't given a link to the entire cooler, only the compressor.
> The configuration of these varies widely and depends on the unit ordered.
> 
> Some are just a box with panels that need assembled and a door installed.
> ...


Most of that is spot on the only thing I am going to disagree with is the mullion heater, I've never worked on a box without them, every domestic refrigerator has them as well, as you mentioned to eliminate condensation around the door(s).

When the specs say the lights come prewired often that just means there is EMT run in the panel that terminates in a surface mounted box, nothing to write home about.


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## 3DDesign (Oct 25, 2014)

MechanicalDVR said:


> Most of that is spot on the only thing I am going to disagree with is the mullion heater, I've never worked on a box without them, every domestic refrigerator has them as well, as you mentioned to eliminate condensation around the door(s).
> 
> When the specs say the lights come prewired often that just means there is EMT run in the panel that terminates in a surface mounted box, nothing to write home about.


Here's a link to a Cooler box. At the bottom of the web page under walk-in doors, it says freezers come with door heaters but units above 35ºF do not. Every cooler I done with glass doors have had heaters though. I agree it's a better option to have them.


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## MechanicalDVR (Dec 29, 2007)

3DDesign said:


> Here's a link to a Cooler box. At the bottom of the web page under walk-in doors, it says freezers come with door heaters but units above 35ºF do not. Every cooler I done with glass doors have had heaters though. I agree it's a better option to have them.


The 35F a the factor, it would be rare to order a refrigerator box that would be kept above that, to maintain your perishables below 40 the box itself would stay cooler.

I haven't been the guy to order the box or spec them just connect and service them and have never worked on one devoid of heaters around the door.

It's easy to see when the heaters are not working typically there is a puddle on the floor under the door.


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## 3DDesign (Oct 25, 2014)

MechanicalDVR said:


> The 35F a the factor, it would be rare to order a refrigerator box that would be kept above that, to maintain your perishables below 40 the box itself would stay cooler.
> 
> I haven't been the guy to order the box or spec them just connect and service them and have never worked on one devoid of heaters around the door.
> 
> It's easy to see when the heaters are not working typically there is a puddle on the floor under the door.


Even when I buy beer and go inside the walk-in, I can feel the warmth of the door.


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## MechanicalDVR (Dec 29, 2007)

3DDesign said:


> Even when I buy beer and go inside the walk-in, I can feel the warmth of the door.


Yeah man, and the colder the box the more obvious it is.

But in most commercial applications the workers could careless and things go unnoticed until there is an obvious problem like puddles on the floor that are there until an inspector points them out to management and then it's a priority rush job to get the problem fixed before the inspector comes back.


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## ggratecc (Mar 25, 2008)

guys,
I found a spec sheet on the internet: http://www.americanwalkincoolers.com/pdf/AWICR-404AOutdoorCondenserUnits.pdf

use the line for RM100-PR, single phase.
the evaporator fans (2) are each 1.8 FLA, 115v.
Apparently the defrost is Air. 
I'm not sure if the door has a heater.

I now see there is plenty of electrical work to be done just assembling the unit and running electrical inside. There is mention of wiring harnesses being supplied on this unit, so that should make it easier.


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## ggratecc (Mar 25, 2008)

MechanicalDVR said:


> That is assuming there is a digital temperature readout and the evap fans are 120v.


verified the evap fans are 120v, 3.6a total.


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## ggratecc (Mar 25, 2008)

MechanicalDVR said:


> Welcome aboard ggratecc! Enjoy your ride here.
> 
> 
> Are you working as an electrician or an EE and someone else is doing this install??


I am working as an electrician and doing the install. Thanks for the warm welcome and the nautical theme.


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## MechanicalDVR (Dec 29, 2007)

ggratecc said:


> guys,
> I found a spec sheet on the internet: http://www.americanwalkincoolers.com/pdf/AWICR-404AOutdoorCondenserUnits.pdf
> 
> use the line for RM100-PR, single phase.
> ...


On a typical 8'x10' box you'd have a surface mounted box with a vapor proof light fixture right inside the door on the hinge side controlled from a switch in the door panel.


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## ggratecc (Mar 25, 2008)

MechanicalDVR said:


> On a typical 8'x10' box you'd have a surface mounted box with a vapor proof light fixture right inside the door on the hinge side controlled from a switch in the door panel.


MechanicalDVR,
Sounds like the lighting on this box should be 1 amp or less.
Unlikely there will be defrost heater for this chiller or door.
Unit will be installed outdoors, 15 ft clearance from nearest bldg.

Therefore I'm concluding:
1. 115v , 15A circuit for Evap and Light(s).
2. 230v, 15A circuit for Condenser unit.
3. supply panel will be indoors of adjacent bldg. (gymnasium).

I am listening to all advice, so keep it coming. Project manager board will probably proceed with purchase after July 5.


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## MechanicalDVR (Dec 29, 2007)

ggratecc said:


> MechanicalDVR,
> Sounds like the lighting on this box should be 1 amp or less.
> Unlikely there will be defrost heater for this chiller or door.
> Unit will be installed outdoors, 15 ft clearance from nearest bldg.
> ...


Sounds like you have the circuits covered.

You need to find out if the condenser is going to run off a pressure control mounted on the unit itself or they plan on a thermostat inside the box you need to wire up.


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## ggratecc (Mar 25, 2008)

*End Game*

All,
you deserve to know the final outcome of this job. The facility manager did some research and consulted with me. We purchased a used 24' insulated shipping container, 8'x8'x24. The refrigeration equipment had been removed from the end. We only had a 240V single phase source panel inside a gymnasium.
We purchased an LG 24,500 btu A/C and installed in the end wall up high. I finally cut the rectangular hole with angle grinder and recip saw.
Now you're gonna say that's not cool enough, but we bought a "coolbot" controller and connected to the A/C unit.
I ran 80' of 3/4" EMT from panel to the outside parking lot where the container is. All done at the 8' level above grade on the brick exterior.
Then pulled 4 - #12 wires and terminated to two bell boxes on the interior of the container, a 20A 240v outlet, and a 120V outlet for the controller and future lighting. 
Even With many full pallets of groceries inside, we quickly got the temp down to 40 degrees!
The non-profit board is very happy, they previously wasted 80% of the food donations, now distributing about 80% of the perishable food.
The main reason we did it this way was to easily transfer full pallets in/out without breaking them down.

Thanks again for all of you who gave advice on the original post, I learned a bit on this one.


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## MechanicalDVR (Dec 29, 2007)

ggratecc said:


> All,
> you deserve to know the final outcome of this job. The facility manager did some research and consulted with me. We purchased a used 24' insulated shipping container, 8'x8'x24. The refrigeration equipment had been removed from the end. We only had a 240V single phase source panel inside a gymnasium.
> We purchased an LG 24,500 btu A/C and installed in the end wall up high. I finally cut the rectangular hole with angle grinder and recip saw.
> Now you're gonna say that's not cool enough, but we bought a "coolbot" controller and connected to the A/C unit.
> ...


What kind of outdoor temps are you maintaining 40F inside with?


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## ggratecc (Mar 25, 2008)

MechanicalDVR,
I would say it was in the low 80's. it works great because the container is on the northside of a 24' high gymnasium, very shady place.


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## ggratecc (Mar 25, 2008)

*Project followup photos*


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