My commercial freezer cycle on/off a lot lately. It is also not keeping as cold of a temp as before. In the morning it used to be -13F now its around 5F, during the day it will rise to as much as 24F. Any ideas on what could be causing this? Unit just over a year old.

20 years ago guys used to put a 50 watt bulb down in the compressor area BUT the freezers today have been designed with the condenser in the freezer wall and don't retain any heat in the cold weather. Generally what you will experience is the temperature in the surrounding area drops to 10 degrees the freezer goes off and when the area begins to warm up the compressor tries to start with syrup for oil in its crankcase and cycles on its protector until it gets hot enough to warm the oil and allow it to run. Compressor life is shortened and the freezer temp is unstable. A self regulating crankcase heater could be purchased at a local supply house and wrapped around the compressor but I don't know if its ever been tried on a compressor that small or if you might overheat the compressor. ............Can you say garage heater? Its a matter of system design. All of the components for a commercial conversion are out there but a system that small is never considered. Sorry wish I could help more. Hope this helps and good luck.

have you checked the door switch for each door? the lights should still work in defrost mode but not fans or compressor.

Hello David, thank you for your question! Based on the symptoms you are describing, it sounds like the issue may be related to a possible wiring failure between the thermistor and control or the control itself is faulty. At this point, I would recommend having a service technician to diagnose the problem before investing in unnecessary parts.

Most all commercial freezers like yours have, what is called, a fan delay. It is located in the evaporator case and is usually attached on or very close to the actual cooling coil. It may also be a combination switch known as a defrost terminator/ fan delay. It's purpose is to keep from circulating warm air. If the cooling coil does not reach a preset temp, the fans do not come one. Another thing is that the fan motor may just be bad. If you have more than one fan, then chances are that it's going to be the fan delay. I would start there to see that either the fan delay switch is bad or there is a reason that the coil is not getting cold enough to activate the switch.

When the temp gets back down to running temp the vacuum will return if the gaskets are properly installed.

If you need further help, reach me via phone at https://www.6ya.com/expert/dan_73bbd84fe1d95b61

Most all commercial freezers have a fan delay/ defrost terminator. It is usually mounted on the end of the evap coil. It's purpose is to sense the temp of the coil during the defrost cycle. When it hits a preset temp., usually around 55 degrees or more (depends on Mfg.) It terminates the defrost cycle. It also doubles as a fan delay. It allows the evap coil to cool off from the defrost cycle before allowing the fan to come on. Usually, the coil has to get around 20 degrees before fan will energize. I would look for this as a possible problem. It could be one device with 3 wires or 2 separate devices with 2 wires each. I've seen it both ways.
Hope this helps.

Freezer temps can very, but as we know freezer temps can run from +32F to -40 or more on commercial boxes with the different freons. But back to you, I would say from my charts on low, med., temp refrigerators, you should be around +8F to -5F. When I mentioned +32, we know that's when water starts to freeze, so you want the freezer to be much colder then that.In order to keep ice-cream frozen, you must cycle around -5f to -10f.I sincerely hopes this has helped you out, as you will I am sure get many different opinions, but +8 to-5 is excellent for this box.
Sincerely,
Shastalaker7

Freezers have a sensor that is referred to as a "Fan Delay/Defrost Terminator". It senses the temp during the defrost cycle. Usually, when the evap temp reaches about 50 degrees, there should not be any frost or ice on it. This device terminates the defrost cycle. It also keeps the fans off so warm air is not circulated. When the evap gets to about 20 degress or so, the sensor switches on the evap fans. If the fans are not coming on, either the sensor is bad or the evap is not reaching the proper temp to cause the sensor to turn on the fans.

Hope is helps to clear up some things and point you in a direction as to what might be going on.

seems that its low on water or float switch is bad. try to clean float

The ice could be preventing the freezer from freezing properly, try defrosting the unit. if this does not help then this could indicate a more serious problem like a bad temp sensor or refrigerant leak.