Air Con leak sealer - safe to use or best avoided?

[Big Mark]

Getting my air con re-gassed on Friday by a mobile air con guy (car currently immobile) and during the discussion I mentioned that I must have a tiny leak somewhere as I have to re-gas at the start of each summer and he said that he can put a leak sealer in the system.

 

Is a product best avoided or is it ok? Plan was to re-gas now with UV die and get it fixed by a specialist in Autumn/Winter when the UV die will hopefully show where the leak is.

[rider]

If you need to re-gas each year are you doing it properly, by pressure or weight? By sight glass filling? Or just till it starts to blow cold again? If the latter then you will probably be starting from a low charge as the Low Pressure cut off is generally around 10psi for the a/c clutch to activate which will be way below the normal LP suction pressure and specified charge weight.

 

Assuming you are charging to the correct weight of refrigerant then a small leak can be cured with leak sealant though I'd look for it first around the valves which are usual culprits and easy to change. Though you should remember that a normal system would do with a recharge every few years anyway as all hoses are porous before any leaks hit the system.

 

Here is a video link worth a look for anyone thinking of tinkering with their a/c. I charge mine on the LP port until it reaches 20psi on the suction (with compressor running) on a cool day and that works fine with a top up needed every 3 to 5 years.

 

 

There is one thing the guy does on the video that I was told is a no no. Inverting the gas cylinder to feed in liquid is by far the fastest way to charge a system but I was told by a refrigeration engineer that is bad practice as you could liquid slug the compressor, effectively hydraulicing it. So I always gas charge. Slower but apparently safer.

Edited July 6, 2015 by rider (see edit history)

[Dnk]

Call Ibrar, he does re gassing and checks the system properly, putting in a sealer is a bodge in my book, just like rad weld.

 

If it's got a leak fix it properly

[Big Mark]

I agree that rad weld is rubbish and best avoided but reading up on air con systems and there's a lot of talk about sealing kits and even some refrigerants having sealer in them as the systems are so prone to leaking.

 

I want it working this weekend so might just get it just topped up with a UV die in it and hope to find the leak in a few months with a UV light......................