Compressor run for 3 mins then off for 10 mins

[sanya]

Hi there, please help me on the commercial refrigerator using r12 , compressor was run for 3 mins then off for 10 mins then on for 3 mins again and again but condenser fan and evolorator fan still runing , inside box is about 50F when the compressor run it's colder but only few mins , I was put my gauge on liquid line at drier reading 120F when compressor run and I was low side gauge at compressor process tube reading 10F when compressor run, ambient temp about 70F , You think this system is low charge, temp control or relay? Thank you for your help

[frank]

based on the limited information, I would offer a guess that it's cycling on klixon due to overheating caused by a lack of refrigerant charge.

A lot more information is need to make an educated diagnosis I'm afraid

[sger9]

Hi there Sanya. The first thing Id check is Your condensor. Make sure its not gummed up especially if its in a kitchen. also some older units used an over pressure switch between comp and cond. They go faulty and depending how its wired will shut the whole unit down or just the comp.Hope its that simple.

[sger9]

Also thought of klixon on comp. If thats dodgy it will shut down just the comp. Norm wont stay off that long unless the comp is running really hot.

[Gary]

My guess would be dirty condenser.

[chemi-cool]

And my guess is a low charge and low pressure control stops the compressor.


What doe's the winner get??

[mwangi]

hi,if the fridge has a low pressure cut out then we have an under charge if not the compressor is overloaded or the filter drier is partially blocked. try flushing your system

[Yuri B.]

So much attention to a trifle problem - just look where circuit breaks: that's it (then think a little - why). Let this thread's originator get used to a voltmeter also.