Out of nowhere, my Nor-Lake walkin cooler has begun to run so cold that it is freezing my produce. I have had it for about three years and have never adjusted the thermostat until this problem began. I don't know if it has something to do with the heatwave that we had or not. I turned the thermostat up to 50 degrees and still no help. When I went to check on it this morning, it was at 19 degrees. Any idea what the problem is?

Diagnosing Walk-in Coolers & Freezers Problems

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Jun 7, 2013 - Diagnose Walk-in Cooler & Freezer Refrigeration Problems ... For many evaporator units, the ice isn't melted, or the water isn't .... It works for few days (2-3 days) and it stop and does not run until I shut off the power .... My walk in compressor seems to be running and not shutting off. .... outdoor ambient= 85

Maintaining & Cleaning Your Walk-in Cooler or Freezer

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Jan 7, 2015 - Torn gaskets can let warm air infiltrate your walk-in cooler or freezer. Close the door when not in use. Do not block or prop the door open for extended periods of time. ... on suction lines between the condensing unit and evaporator coil. ... Make sure the lights are off when exiting the walk-in. ... clean walkin ...

[PDF]INSTALLATION & SERVICE MANUAL - Polar Leasing

Defrost Timer on walk in cooler

Odds are your temperature is too cold in your freezer. If when you moved you just plugged in your freezer without adjusting your temperate for your new location you accidentally froze whatever water was coming into your freezer.

First you will need a cooler for whatever you have in your freezer, unless you have wonderful neighbors who will let you keep your food in their freezer for couple of days.

Take note to see what your freezer thermostat is set to. Turn off your freezer. Take out all the food. Keep the door open. This would be a great time to clean your freezer. Let the freezer thaw out for at least one day. Check the line to make sure there is no ice. Once everything has melted turn your freezer back on. Turn your freezer back on but this time set the thermostat to three or maybe 4 levels below what you had it set to before.

Finding Freezing level:
Fill an ice cube tray or small plastic cup with water. Put it in your freezer and come back in about three hours to see if has begun to freeze. If it has not begun to ice raise your thermostat to make you freezer colder by half or 1 level. Leave the ice tray or cup of water that you originally placed in the freezer but add another one. Come back in three hours to see if the water has frozen or has begun to freeze.

You want to leave the original water because you need to make sure the new water does not freeze solid as fast as the original water. If it does your freezer is too cold again.

Repeat "Finding Freezing level" until the water begins to freeze but does not freeze solid. Once your ice begins to free you can put your food back into the freezer. Wait a couple of hours more to see how much more your cubes freeze. If they are hollow or still watery in the center you should go up another half level and check on it the next day.

Once your cubes freeze solid you should be all set. If you don't get at least one tray of ice per day from your freezer you could go up another half level so your ice freezes faster.

Be careful about making your freezer colder because you might end up with the same problem you started with depending on how sesitive you thermostat is.

Your air temp should be at least 20 degrees cooler than the indoor air temp. This is ideal. But it sound like your unit is low on freon. When units get low they will freeze up. They will also freeze up if air flow is restricted on the inside coil or the fan quits on the external unit.

replace the cold control

The evaporator drains into pan with a coil from the discharge line. The design is intented to sub-cool the liquid refrigertant as well as evaporate the condensation from the coil. Unfortunately the engineer started as career a shipping clerk and never received any further training.  There isn't enough heat or running time to evaporate the condensation from the coil.
The solution is fairly simple
A plastic tube  drains water out of the evaporator in the pan. You can extend the tube and add a defrost pan handled by your refrigeration wholesaler. Wire it so it is on whenever there is power to the unit.  This should get rid of the excess water. These pans are also used on some self contained coolers and freezers. They come in either 120 volts or 220 volts. [email protected]

First, I think it’s important to know that the Ref side has no cooling coils, it’s basically a box and the cold air in the freezer is blown over by a fan through a channel into the Ref side. This channel has a door which regulates how much cold air goes through. You probably have two control knobs in the Ref side, one controls the temp with numbers 1-9, 9 being the coldest. This temp control tells the compressor how long to run. The other control is for that little door and it may have letters A-E, E being the coldest. If you set it on E (coldest) then this will close that little door and keep most the cold air in the freezer.
So, how can the Ref side be cold and the freezer side not freezing?

1. Coolant leak. There is enough coolant to keep the Ref side cool but not enough to freeze on the freezer side.

2. Defrost system failure. The coils on the freezer side are clogged with ice and it's just a matter of time when the Ref side won't cool either. The back wall in the freezer will be covered with ice/frost

try door switches

not all causes are a FREON leak. is the compressor running

They are usually mounted on the front panel of the evaporator or mounted on the wall behind the evaporator.There is a possibility that the temp. control is at the condenser,and the sensing bulb was slipped thru the wall.Look for the bulb at the back of the evaporator and follow the cap tube.