Hi My name is Mark. I have returned to work in the UK after being inBrsbane australia the last 8 years. found out R22 is to go soon and my new company is getting enquirie about retrofit to R417a or R422d. DuPont claim 'O' rings and elastomeric seals will most likely leak after retrofit. has anyone experience of retrfits to the above?? did they leak?? did you change seals etc?. I have to submit quotes and do not know likelihood of leaks..