Printable View
Im having a problem with two units not returning oil back to the oil separator you can just see it in the lower portion of the lower site glass under a full load or half loaded it does'nt matter. Am I low on oil or what the oil pressure is about 25 to 30 psig lower than the head pressure I'm not sure if this should'nt be somewhere around 20 psi diference can anyone help me on this one.
ryoungbe:)Quote:
Originally Posted by ryoungbe
I'm sorry but I just can't make sense of your post. Please reword and post again.
Oil does not return to the separator but from it to the compressor:confused: and how could high oil pressure cause an oil return problem.:confused:
Kind Regards Andy:)
If by the lower sight glass,I presume you mean the lower of the two on the compressor[if its a j compressor].J compressors are notorious for not bringing back oil to the sump when running under low load conditions.Let it run fully loaded and oil should return.
Also,if you can see an oil level in either glass.Thats fine.
ryoungbe
Its fairly normal to only have a level in the bottom of one of the two oil sep's/receivers, only on prolonged full load with proper water flow etc will you get a better level.
the oil circuit has a transducer before the oil filter and one in the comp body, only when this falls below the preset limit will you get an oil trip.
it's vital that you check your water pressure drop to ensure that the chiller can operate properly.
Al
If you running a york screw compressor you should have 1/2 a sight glass on top or both sight glasses at full load. If you are losing oil from seperator you may be having trouble with system EXV or TEV settings especialy if your using R407c. Check your discharge superheat is at least above 10k with 20 to 30k being ideal, too little or too much will not allow correct seperation. Also head pressues are critical for oil pressure as it is used to force oil from seperator through filter into bearings.
Add oil so that you have at least half the lower sight glasses full. You may find that at full load the level is above the upper sight glasses and the liquid line sight glass is a milky colour but it is better than having low oil level. Low oil level can destroy the oil filter!