View Full Version : How can you ensure correct oil level on a compressor with no sight glass

31-08-2014, 07:27 AM
can someone help me with this question, you arrive on site and find that alarge leak has resulted in considerable loss of oil, from an hermetic compressor, you repair and then have top the oil up but there is no sight glass fitted to the compressor to show where the level should be,how would set about ensuring that the compressor has the correct amount of oil in it?

31-08-2014, 07:54 AM
Before fixing it, you should drain oil from compressor and recharge to specified amount by measuring volume of charged oil. Keep in mind 10 min. Cummulative time limit for exposure to open air for POE oil.

That is not aplicable to rotary hermetics with high side at compressor housing. You cannot drain them without drilling hole in housing.

Another methotd is by comparing weight of compresor (and oil charge} with new identical one!

01-09-2014, 08:39 AM
thanking you

01-09-2014, 04:52 PM
You can also use an infra-red thermometer on the compressor casing working from the bottom to the top. You will see a difference in temps where the oil sits in the bottom.(Obviously there needs to have been a short operating condition before measuring.) Make sure that the crankcase heater is off though. ;)