I read on an A/C forum how they prefer to charge through the high side with the tank upside down so the freon is a liquid. When the car won't take any more liquid freon, turn the tank right side up, start the engine and add the remainder as a gas. Just tried this for the first time and may just switch to this method. Certainly took much less time. Anybody else do it like this?
Charging A/C through high side as a liquid.
- Thread starter atikovi
- Start date
That's how my machine does it.
The high side pressure can reach over 400 psi. This is way beyond the releif valve pressure of the small 12 oz cans of r134a. Perhaps you used and stronger/larger cylinder. I don't think this is the best advice.
Perhaps someone knows the exact specs of these containers.
Perhaps someone knows the exact specs of these containers.
When you add it as a liquid, the compressor shouldn’t be running-then, when it can’t take any more, shut the high side valve, flip the tank, start the car/compressor, and add the rest to the low side as vapor. Liquid in the low side can damage compressor valves if it stays a liquid & “slugs” the compressor.
You don't do it running and if your seeing 400 psi something is wrong.
You can’t add liquid to the high side when the compressor is running, the system pressure will be higher than in the cylinder! Fortunately the tank valve is generally a one way valve to prevent refrigerant from being forced back in.
Any guage set made in the last 30 years has a restrictor in the hoses to prevent slugging a compressor.
So what happens if it won't take a full charge as a liquid. You can't just turn the tank right side up in the machine and finish on the low side with the compressor running?
The machine has a heater that will heat the internal tank and push the refrigerant in.
I have a heater on my tank but didn't use it because it was full and didn't think it would need it. Wouldn't take the last 8 oz as a liquid so had to turn it over and run the compressor to draw it in. If the heater was on would all have gone in as liquid?
As long as the heat makes the pressure rise enough it will.
