Short cycling, it makes me think of riding a bike a very small distance, or someone riding a really short bike…. actually it’s when a motor or compressor runs for a short period of time and is off for a short period of time. This will shorten the life of said motor or compressor.
We have had our current/new freezer to fridge conversion for a couple of months now, as the weather began warming up, I noticed the box ran more often than I thought it should, so I really started paying attention to the cycle. I didn’t officially time anything, but I estimated it was coming on for only a few minutes at a time every 5-10 minutes, that was definitely wrong. Of course this was during 100 degree days, it was also happening that way whether I opened the lid or not.
I looked at the probe to the external thermostat, since my new box is smaller than my old one, the probe didn’t have any free space to hang within, it was shoved right up against the wall of the freezer, that’s where the cooling coils are. So when the inside of the box warmed up sufficiently, the probe would alert the control box where the thermostat is housed, it would allow the power to run to the box until it reached the set temp, which was 35 degrees F, just above freezing.
With the probe being right up against the wall, which froze almost immediately, the probe detected a lower temp than what was really inside the box and turn off the power to the unit. The frozen wall would immediately thaw and the ambient temp inside the box still wasn’t at the correct temp, so this went on over and over. This is not a flaw in the external thermostat, in fact it worked perfectly, the flaw was in the placement of the probe.
I had heard about people putting their probe into a bottle of water, I didn’t want that kind of differential in temps inside the box, I just needed something to keep the probe from touching the wall and protect it from anything else hitting it.
PB cut a length of one inch PVC pipe, it was just over a foot in length. I inserted the probe into the pipe and set the whole thing back in the corner of the box. I gave it a few hours to adjust and come to temp. Then I timed the cycle, without opening the box. I did this 2X in a row. Each time I got the same time cycle, 28 minutes off and 8 minutes on, that was with the sky castle being at 80+ degrees F. I am quite happy with that.
I plan on timing the cycle when the temps are much higher inside the sky castle, and when they are low, but for now, I’m happy with that, it doesn’t cycle much differently when I open the box and remove or replace items, it’s much more stable now.
This is also much easier on my inverter and batteries, each time the unit comes on, it surges up to nearly 9 amps then settles back to much lower to finish its run time. When you are your own power company, you have to be able to troubleshoot the things that can and will go wrong, they are often easy to track down and fix, but other times they are more elusive. Fortunately this was an easy and cheap fix.
You can read about my previous freezer-fridge conversion here:
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