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Trouble-Shooting => Refrigeration => Topic started by: RMphy89 on August 11, 2015, 02:59:10 am



Title: Temperature Just Wont Get Low Enough
Post by: RMphy89 on August 11, 2015, 02:59:10 am
Hello everyone,

My Vendo 110's cooling system has been testing my patience lately. Granted the machine isn't perfect, but it was working pretty well just a few weeks ago. And those few weeks ago is when I installed a new thermostat. Before the thermostat went in, the machine was actually getting too cold, about 29 or so. I put the thermostat in and got it to run well (Cooling to 32 and cutting back in at about 42) Now when the machine gets to about 35 / 36 the temperature starts to go back up! And the compressor is still running. Any ideas what could cause this? I did rewire the light inside the door, which required me to remove the inner door panel, could the door seals not be seating correctly? A refrigerant issue? Thanks!


Title: Re: Temperature Just Wont Get Low Enough
Post by: johnieG on August 11, 2015, 09:08:07 pm
I assume you didnt use the "$1.99 special", as cheap t-stats tend to drift, just a thought.


Title: Re: Temperature Just Wont Get Low Enough
Post by: Slapshot42 on August 11, 2015, 11:33:23 pm
Did you order a contact or noncontact t stat?  If you have a contact and the end of the probe isn't touching the cabinet directly that could be causing the problems.

Also there are "cut in" and "cut out"set screws on the t stat to adjust when the t stat turns on and off.  If the t stat is out of adjustment it could be shutting off before it gets cold enough ...

I'm NO expert I just recently bought a new one for a customer and the instruction provided explained it a bit!



Title: Re: Temperature Just Wont Get Low Enough
Post by: RMphy89 on August 12, 2015, 12:01:48 am
Thanks for the replies. I believe the thermostat is working correctly. The unit was cooling correctly with the new thermostat before. My problem right now is that the temperature gets to about 35 and then rises abruptly, all while the compressor is still running. So in essence the compressor never shuts off and the temperature just bottoms out at 35 and then rises again.

Also, I'd like to note that every time the unit has done this, I've unplugged the machine and plugged it in a few minutes later. After I plug it back in the compressor refuses to start until it cools off (You can hear the little klixon element clicking on and off inside) The weird thing is that The compressor is still running when I unplug the unit. I don't know why the klixon decides to trip after the cord has been pulled.


Title: Re: Temperature Just Wont Get Low Enough
Post by: cohammer on August 12, 2015, 01:21:37 am
Sounds like you just need a better thermostat if the compressor cools that good . Or get the thermostat bulb in the correct position.


Title: Re: Temperature Just Wont Get Low Enough
Post by: MoonDawg on August 12, 2015, 07:45:07 am

 After I plug it back in the compressor refuses to start until it cools off (You can hear the little klixon element clicking on and off inside)


          Your system is telling you something.
          While the compressor is running it is building up pressure in the high side lines.
          When you unplug it, the high side pressure must be reduced to equal low side pressure before it will start again.
          I have found 5 minutes to be ample time.