View Full Version : Using mineral oil on SZ Danfoss compressor

22-05-2016, 01:42 PM
Hello all .

I need information to solve a problem with chiller .

I need to Replace 3 broken compressors in water chiller .

The original compressors are Danfoss - SM185 Performer using Mineral oil and R417a refrigerant .

I want to use used SZ185 danfoss compressors which use POE oil .

Can i change the oil for SZ series performer with mineral oil ?

22-05-2016, 03:34 PM
Its the same compressor but with different oil.
Pour the POE oil out, let it drain real good and fill with mineral oil, no problems.

22-05-2016, 04:32 PM
R417A is unsuitable for chiller application. Remember reading somewhere it was only suitable on AC units up to 15 kw. What size chiller do you have. R438A (M099)is the preferred blend but I would recommend replacing the chiller.

22-05-2016, 05:00 PM
The machine is chiller + 4 way valve for heat pump . It is double circuit with 4 compressors SM185.

Original the machine is with R22 refrigerant ,but i think i did mistake and replace the R22 with R417a directly without change the oil with POE as the Danfoss recommend.

Now after 4 months working the machine stops and 3 of 4 compressors are out .

What about if i back the R22 in the machine and change the oil with new mineral oil for all 4 compressors ?

22-05-2016, 07:30 PM
Does it have a suction accumulator fitted ? I would have changed the oil to POE or at least added POE oil to the mineral oil to ensure better oil return. Suspect your compressor problems are probably oil related.