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Adding refrigerant to a/c

I have a 200 Subaru Forester that needs more Freon/refrigerant. Is this something I can do myself (I am pretty much a car dummy tho I do know where various parts of the engine are) or do I need to take it to my mechanic because it involves the compressor?

In my opinion anything involving the AC system requires properly trained and equipped professionals. I know they sell refill kits in parts stores, but I don’t mess with them.

If the system needs more refrigerant it’s because there is a leak, and simply adding more refrigerant won’t fix the leak.

I would take the car to someone who has the necessary equipment to find the leak, repair it, evacuate the system, dry it, and refill it with the correct amount of refrigerant.

I agree, it is best left to a professional. Car dummy + A/C system = disaster.

Let me put it to you this way, there are PROFESSIONALS who are dangerous working on A/C systems so dont feel bad, its just one of those things.


Since a properly functioning AC does not consumer refrigerant, then you have a leak. That leak may be very small and if you need to add a little refrigerant every couple of years, maybe you can DIY following the instructions that come with the kit, but …

I recommend a pro, as they can check out the system, get the right amount in there (too much is just as bad as too little) and can look for and if needed fix any leaks.

First, I don’t believe your diagnosis can be trusted. All you know at this point is that you are not getting air as cold as you would like. That isn’t necessarily because you need more refrigerant. Also, if you need refrigerant, there is probably a leak that needs to be fixed before you add more refrigerant.

If you were not a self-professed “car dummy,” the job of adding refrigerant is something you could probably tackle, but chances are, it won’t solve your problem. Take it in for a proper diagnosis and repair.

Agree with others; take it to a professional A/C shop. My last car had a small leak, and every few years it needed topping up. I got an inspection and a top-up for about $50. Not worth trying to do yourself!

I’ve had trouble with low refrigerant over the past 16 years, but not frequently. What I found is that some auto techs like to leave the connectors or connector covers loose. After making sure the connectors (for adding refrigerant) are firmly tightened after each shop visit, I no longer had any problems. Some time after 10 years, some flexible hoses seem to develop leaks, but usually not if the refrigerant oil is at a proper level. My take on this after doing a lot of research is this: if the compressor is replaced or if the system has lost refrigerant pressure, the accumulator and all flexible hoses should be replaced as well as flushing the system and complete evacuation before recharging. However, not being an auto tech, myself I question whether the complete evacuation might harm the compressor. Will the experienced auto techs please comment?

I also found that on my minivan, a 1998 Chrysler T&C LXi, (with dual air) the defroster uses the A/C to remove moisture which probably negates the need to frequently run the A/C during the winter.