Walk in not cooling to temp and freezing up

I have a Capsule Pak walk in cooler that has functioned well for the past 4 or 5 months after some problems with getting the pressures adjusted and sealing holes in the walk in itself. Recently, the threshhold broke and the humidity (i suspect) caused the coils to frost up pretty good. We defrosted it as I have dozens of times previous and replaced the threshhold. I closed the door in the walk in and turned the lights off to make sure there were no leaks. However, it only cools to 39 degrees or so before it keeps frosting up.

I defrosted it again this time thoroughly with hot water and a blow dryer until I was sure it was totally frost free. Still have the same problem.

Other than the the threshhold, there are no changes in the walk in. The defrost cycle is the same, etc. etc.

Any ideas?

Thanks in advance.


As a long distance diagnosis I would guess that it is low on gas. Do you have a good relationship with an a/c and refrigeration guy?

Rick is spot on.
We had ongoing problems such as you described and each time it was low on gas due to minute holes or dry seals.
After too many visiits from the refrig mechanic the compressor gave out and we had it replaced as well as the evaporator inside the coolroom at a cost of $7,500. Insurance covered $5,000 and the rest was recovered in less than a year as our power bill dropped $300 per month afterwards. Food stayed fresher and wastage reduced.
If it is continually happeneing then it’s probably time to get it replaced.

You may want to make sure your compressor is getting good air flow. I was having a similar problem with my cooler and cleaned the filter/metal screen in front of the compressor and the cooler immediately started working great. A wire bush and a little water is all I needed. I hope this works for you.

Hi Patrick:

Lots of good suggestions here. Generally your problem indicates low on gas but it may be one of the other suggestions.

George Mills

Yup. our “walk-in” is a 8X10 super-insulated room with a door that enters directly into our kitchen. Our hot & humid kitchen. In the winter, no problem but like the swallows return, with summer in our house it means the condenser in the walk in needs to be not only washed with hot water every 30 days minimum, but we also use a spray degreasing agent on it, then rinse with the hot water. If we forget…it reminds us by freezing a huge ice block which of course drips everywhere and makes a general mess of stuff! I’m pretty sure our only cure would be to someday afford to toss a new walk-in unit outside and kick a door through the current “walk-in” that would work to insulate the new one from the kitchen humidity. So, I’m taking donations if you’d care to send whatever you can afford… :lol:

I had a similar problem, It turned out to be a defrost timer switch. replaced by local refridgeration co for about $475

When I had this problem, I got told to check the fan behind the evaporator, when I shined the flashlight in there, I had a huge block of ice on the side that was not visible without the flashlight.

If yours has a fan, check to make sure that is working.

Clean the compressor. If it’s sitting on top of the cooler you may want to put a small fan (anything that will fit) on top of the cooler to get air moving. between you kitchen heat and the compressor motor it will make it quite toasty up there.

and the main thing, that others have stated. Freeze up’s mean that your compressor is over working, if it continues you will want to get a pro in there to check it out before you burn up the compressor.

Not wanting to steal this thread…but how many out there use remote refer setups? With all the flour and heat issues from a pizza kitchen…I was wondering if the extra expense would be money well spent?

Mike, Our compressor is in the basement well away from the heat of our kitchen. Your comment brings up a very good point however. We have it on our “monthly” jobs list to clean all the equipment condensers. It’s scary how dusty and greasy those fins can get if we forget to keep them clean! If the heat can’t get out of the line…dollars are sure to go “in” soon!

I install remote compressors whenever possible on immobile cooling equipment like walk-in coolers and ice machines. The one-time added cost of piercing the roof and running some longer lines should quickly be offset by not having all that heat constantly dumping inside the building and adding work for the A/C.

The reason I ask is the Kairak BLu line of products. One rooftop unit to cool the walk-in and prep with glycol based coolant. They are a bit pricey but two good points…first, less wear and tear by having the well ventilated unit up top, and second, their Blu system is said to cut operating costs by 39% if I remember correctly. That could pay for itself in a couple of years easily. I know that having one unit is a risk if it goes down, but it also is only one unit to keep up. Just a thought. :idea:

When we had to replace our compressor which was on the roof of the coolroom , we had it put up on the roof. A little more expensive but it cooled the prep area, and the shop in general, down by heaps and the unit runs much more efficently.
We were for ever cleaning the unit and it was always very hot to touch. Now it is outside maintenance is minimal.

:shock: :oops: :cry: omg we paid 125 to have a new one replaced! :stuck_out_tongue: our new walkin has a remote cooler on the outside :stuck_out_tongue:

Thanks guys. Turns out, the defrost timer was bad! It just spun around freely. While the tech was here, I also had him replace the thermostat b/c the Johnson Control thermo just had too much variance and it made me nervous. The unit is no longer freezing up. HOWEVER, it is not cooling to temp.

The technician checked the coolant level and the temperature of the air coming out and concluded everything was fine. But, after 3 days, it hasn’t dipped below 39 despite me driving the thermostat down.

I’m thinking it may be the location of the sensor for the new thermostat. The thermostat is located inside the capsule pack and the new sensor is a copper wire. That wire is wound further up toward the unit rather than down into the walk in. Can/should I just bend that sensor down closer to the walk in?