redbeard1

Hello,

Last fall I noticed a small hiss when starting the a/c. I looked around the system and noticed a thin film of what looked like oil/dirt around the high valve. I guessed my high pressure shraeder valve to be leaking so I stopped using the a/c as I had read that an empty system can attract moisture and really bad/expensive things will follow.

I finally tackled this problem today. Before attaching the manifold gauges to debug the system, I figured I would test the valve with a screwdriver just to make sure I had pressure. Unfortunately, the valve will not press in. I tried a fair amount of pressure, probably 7x what is needed to depress the valve on the new replacement valve core. I tried the low side (to my knowledge this side is not leaking) and same thing.

As far as I now, these valves have not been touched in 15 years. I’ve read that sometimes the o-ring that seals the valve on the bottom swells and traps the valve. But looking at the new replacement valve core, I can’t see how that type of swelling would be able to resist the force I applied to the valve.

Any idea why they are sticking?

Any ideas to fix the problem?

Tomorrow, I will get a tool to twist off the valve. Hopefully, the valve is not also stuck on the sides.

Some guy on the web suggests using a hair dryer, but that video was for a stuck tire valve. I would not want to apply heat to an a/c system.

redbeard1

Just a quick follow-up in case anyone has a similar problem

Today I received a tool to remove Schrader valves without depressurizing the system (link below). With this tool, I was able to remove the valve and install a new one. System is again sealed. I imagine I lost some coolant during the last six months. When I have more time, I’ll use the manifold gauges to estimate how much to add back.

With the old valve core out, I was able to finally push open its valve. Opening the valve took lots of force. I’m glad I did not apply that force while the valve core was sitting in those aluminum lines.

How to use tool properly

It seems lots of reviewers on amazon could not get tool to work. I figured I might also have trouble, but found a good instructional video.


Tool on amazon

sbstnce

did you get this fixed?

thoiboi

..

redbeard1

Yes, the tool removed the valve without depressurizing the system. I then used some manifold gauges to estimate/replace the lost refrigerant. A/C was blowing in the low 40s after the job.

Read the instructions carefully. Lots of reviewers seem to hate the tool for not working. Not sure if its user error or just the nature of a complicated tool.

The tool may require some finesse. You may need to gently adjust the tool tip to better retain your valve stem in case the tool does not work on your first try. I was discouraged by some reviews but found the tool "like new" on an Amazon warehouse deal for around $15. At that price, it was worth a try.