How do you recharge air conditioner on a 1991 RV Leprechaun?

Answer 1

You get a certified shop to do it. For one, to use R/R/R (recovery, recycling, recharging) equipment, you need to be either Section 609 or Section 608 certified, depending on what type of refrigerant it uses. Being a 1991 MY vehicle, it was originally an R12 system - which you can't buy without Section 608 certification. To further complicate the issue, since R12 was outlawed a couple years after that vehicle was manufactured, many R12 systems were converted to an alternative refrigerant, which may have been the industry standard of R134a, or R414b, or R22, etc. If you're not the original owner and you're not the one who had that system retrofitted, then you need to have a refrigerant purity test done to determine exactly what's in that system, because you can't blend refrigerants. There's also the possibility that your problem isn't refrigerant, or that, if it is, then it's on account of a larger problem. People just assume that if an AC system blows warm, it must need refrigerant... in fact, there are many possibilities why it could do that, including blockage in the system, contaminated refrigerant, too much refrigerant and/or compressor oil, poor airflow through the condenser (typically due to damaged fins), etc. Not to mention you shouldn't be running out of refrigerant in the first place - if you are, then there's a leak in the system which you'll need to get repaired if you don't want it to be a recurring problem.

AC work isn't a DIY thing, and I just highlighted some of the reasons why. Leave this one to a professional.