Reply to "Converting r12 to 134"

r12 to r134 conversion is not that hard. You dont need new hoses if you had a functioning r12 system. The Mineral oil in the r12 system will act as a barrier to the r134. But if you do change a hose, you must use a barrier type.

Some compressors do experience problems with the shaft seal rubber being compatible with R134 and may need changed.

Thermostatic expansion valves are thermostatic and will adjust for either r12 and r134.

You must add 4oz of Ester oil into the system. It is a synthetic oil that will help the mineral oil flow with r134. DO NOT use PAG oil. It is totally not compatible with mineral oil and is toxic. Initially the only oil for R134 was PAG and this is the reason that all systems required total hose change and solvent flush. Ester oil made conversion much easier. If you have a totally dry system, then use just Ester oil.

Some systems do not have a condensor that is adequate size for R134 to work. In this case, you need to add a new plate and tube design condensor for r134. The pantera is one of those applications, and must have a new condensor to operate correctly. Almost every time a conversion is said to not get as cold as r12, then the condensor is not big enough. R134 will get as cold as r12 and my pantera will produce 35 deg air. My sisters car actually worked better with R134.

With R134, you use slightly less than R12.

Of course, better air flow across the condensor always helps too.

And if they threaten to get rid of R134, just buy a bunch before then.

One advantabe of R134 over other conversion blends is the ability to "top off". When a blend is low, you need to empty the system and fill it fresh because usually only one of the compounds leaks out and then the mixture is wrong. R134 is a single compound. Also, almost no one has equipment to use the alternate blends. Everyplace has equipment for R134.