a/c line

[radrobbie]

What's the procedure for replacing a low pressure a/c line?

[Cat Fuzz]

Originally Posted by radrobbie

What's the procedure for replacing a low pressure a/c line?

Step 1: Take it to an a/c shop and let them do it.
Step 2: Pay them for their work.
Step 3: Enjoy your a/c in the hot summer.

[Gizmo42]

You "can" do the replacement yourself but its just a hassle and you wont save much. You need to take it somewhere to have the 134a recovered (if there is any left in the system), then you can replace the line, then take it back to have it leak checked, put into a vacuum, then recharged. Since a shop has to do most of it anyways might as well let them do all of it.

If the line split or for some reason there is no refrigerant left in the system you can just go a head and replace the line (easy enough to do), also replace the reciever/dryer since it will be full of moisture now. Then take it to a shop to be leak tested, vacuumed, and charged.

[radrobbie]

I replaced the a/c line and drier and took the truck to the shop to vaccum down the system. It checked fine. I put refrigerant in but thought it didn't hold much, about half the can before the pressure gauge on the can said it was high pressure. the gauge doesn't have a value, just a red, yellow, and green range. The a/c works but now that it's really hot it just doesn't keep up. How much 134a should I have put in an empty system?

[oksooner]

Originally Posted by radrobbie

I replaced the a/c line and drier and took the truck to the shop to vaccum down the system. It checked fine. I put refridgerant in.....

Did you have the system vaccum checked and then added the refrigerant at a later date/time? If so, there inlies your problem. You must add refridgerant at the end of the vaccum process. The system will not hold a vaccum unless it is attached to the pump as the filler valves are designed to hold pressure in....not keep it out. I suspect your A/C system is full of air.

[Gizmo42]

Should hold 1.43 lbs if I remember right. You should have had them charge it when they were done with the vacuum. They can weigh in the proper amount and no guessing if its charged right.

You might still have a small leak in the system. Checking for a leak with vacuum is a bad way to do it. Can be done if you leave gauges on it over night and see if it loses vacuum (have to have non leaking gauges and hoses as well). Also taking the guages off, then putting the gauge hose back on can let air into the sytem if its under vacuum. Always charge right after vacuum without removing gauges.