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View Full Version : oil loged evap,



drifter43
08-02-2005, 11:13 PM
What kind of symptoms do you get with this?


Thanks.

westcoast refer man
08-05-2005, 02:21 PM
Drifter,

I would expect your evap pressure to run lower since effectively your evap has lost heat transfer area due to the oil logging. Also, you may or see a lower than normal superheat heat or some valve "hunting" if this is an expansion valve system. I would also expect that your evap TD would be low and not making temperature as well.

Is there a log book at the job? If so, look to verify if oil has been added on an oo-going basis.

R12rules
08-05-2005, 07:57 PM
do a search of this site and bone up on "oil return problems".

One of the issues with poor oil return is low suction velocity.
One of the reasons for low suction velocity is low compressor capacity. (weak pump)

Another reason could be poor piping design. Lack of trap(s) on suction risers. Too large of a diameter of the suction riser pipes.

Improper sloping of the lines which run back to the compressor.

mspanky
08-05-2005, 08:32 PM
The last case of oil logging I came across was a dairy display case. Pressure was normal(run off a rack), superheat was zero, evaporator fin temperature was 60F instead of 25F. That was a dead giveaway. The TxV was also dead quiet due it sensing a flood condition.

Pulling off the bulb and holding it in your hand will usually get things rockin'.