Hitachi Screw Compressor Retrofit

Hello!
Has anyone had any experience of retrofitting a water chiller with Hitachi 6002SC-H screw compressor running with R22? We have a leak on the system and it seems pointless to recharge with R22R post repair. According to some websites Hitachi ship the compressors with POE so oil return can't be a problem with R22. We will change the oil during the retrofit but again not sure what grade/make is best. By the Hitachi UK say they have no experience using retrofits with this compressor so any help would be greatly appreciated!

hi hitachi screws on r22 used bp enersyn lps 68 grade oil
hitachi on r407c the 6005 sc h compressor uses ester 220 grade

what refrigerant are you going to use

Hi Ghaz,
I'm at a a complete loss with refrigerant choice. We've tried R422D on large recips but the performance has not been good and I'm not sure if anyone has used it in a screw compressor. R407C sounds like a good option but I'm worried that glide may be a problem. Dupont are looking at options for us via BOC so we'll see what refrigerant they propose,

With 407c use ester 220 oil other wise the compressor wont pump up pressure