We did all the serviceable seals. Schraeders and caps, EPRs etc. Still have TONS of leaks.
Some seals cannot be changed easily
thats why my company offers a full rehaul when ever we do that type of a job to prevent a problem down the road replace all the valve,gaskets to all the suction and discharge and oil pots etc cause they all start to leak after 1-2 months
So what really makes these gaskets and seals leak? Is it old oil or refrigerant in the system that mixes with this new stuff? the bulliten at dupont doesn't really give a ture explanation. they just advise you to change out above mentioned.
If a system cannot maintain at least a minim velocity of 1500 fpm to 1850 fpm in the suction line the mineral oil will have a oil return problem with a HFC refrigerant. In an R-22 retrofit to R-407C, R-22C or R-22D that falls below that 1500 fpm will have to have the oil changed to Ester oil. So if a compressor unload or an system cannot maintain the velocity will have oil return problem.