My A/C needs re-gassing (AGAIN) and will change it over to R134a from R12. Anything that needs to watched out for ?

 

If it needs recharged, there is a leak somewhere.


A helpful video if doing it yourself.

 

Gave it to an A/c guy.......lets see.

 

not much, if you use a generic kit the oils are compatible, but if it is leaking you need to get it fixed. Simply refilling it means you aren't pulling a vacuum and the system won't get very cold.

Mine has been able to do this about once or twice and taken a year each time to leak down and be useless again, it has never been cold, but enough to at least get me to where I am going without dying. This time it is toast though. I was looking at my hoses the other day to measure them and there is noticeable signs of leakage at the fittings, which I saw a little of before. This time though, I can actually see cracking and holes in the hoses, so I could probably refill it for 30 minutes.

Best thing is to take the hoses off, replace the seals on the compressor, replace the drier, and take the old hoses to a local hydraulic shop to get them re-made (much cheaper).
Put it all back together, pull a vacuum, and refill the system. R134 is a different amount to fill than r12, there is a simple enough formula for it.

Simply refilling often is always a temporary solution, sometimes too temporary.

 

Warning btw! AC conversion kits come with adapters for the hi and low side. Besides the fact that these often don't work, because the valve won't be operated, they can stick up and dent the hood when it is close! Ask me how I know!