We have a customer with several 35year old Dunham Bush chillers curently running on R22. The chiller have Dunham Bush semi hermetic compressors.
They have been advised by a competitor to convert these to R422D. Has anyone any experience of this downgrade/upgrade?
We are concerned about the quantity of R422D to use when compared to R22 and whether or not the performance is going to be reduced as we have read that there can be oil miscibility problems, any thoughts or advice would be much appreciated.
If the upgrade to R422D is not going to be satisfactory, we will be advising to use R22R.
My own thoughts are to leave a 35 year old machine alone, as it is well passed its prime.