More about the excellent danfoss support:

"Dear Mr. Jürgensen,

Thank you for the reply and also for the information you provided.

I'm looking for lower temps on this Chiller. The main idea is to re-charge the unit with R404a and change the original oil with Polyolester. Is there any parts inside this Compressor that have compatibility issues with POE?

Best Regards"


"Dear Mr. Kossatz,

as this compressor is produced years before introduction of fluorinated refrigerants, as R404A or R134,
the materials will not be tested for compatibility.
In our production and products a lot of small and some larger changes were made to ensure this
compatibility, when R134a production was prepared in around 1990.
The filter driers used for R12 are not compatible with R404A or R134a. There is a need to replace it,
as the drying material can crack and create powder particles wearinbg out the compressor or blocking
the capillary.

There is a big risk, that the compressor contains material that will block your capillary (or other
expansion device) when operating with e.g. R134a.

The compressor is, with this denomination, a LBP or MBP/LBP R12 compressor. This means,
the motor is not strong enough to work reliable with the higher pressure of R404A.
Also, the refrigeration system components (evaporator and so on) are not qualified for the
remarkably higher pressure. Possibly the capillary tube has to be adjusted and for sure the
filter drier has to be replaced.

Danfoss can not recommend the change to refrigerant R404A in this system.

A rebuild with a new R404A compressor can also only be done, if the system design is
checked for the higher pressure and the system is flushed to remove the mineral oil content
coming from the R12 compressor."