Automotive Air Conditioning Information Forum (Archives)

Provided by www.ACkits.com

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

Low side valve leak - 0 psi

Pilotando on Fri June 14, 2013 3:17 PM User is offline

Year: 2006
Make: Honda
Model: Pilot

This is my first post. Last summer I bought a 2006 Honda Pilot with 62K miles. At the time of purchase the A/C was blowing warm. The dealer did an evacuation and recharge with die, but could not find any leaks. The A/C was fine for the rest of the summer.

Fast forward to this summer. Last week, during a trip through Kansas, we noticed it didn't cool as much as it should. Foreseeing that I would need a recharge, I had brought along a can of refrigerant and a hose with a basic gauge. So I decided to recharge the system at our campsite. When I connected the hose, at 70F it read 15 psi. When the can was empty it read 35 psi and was blowing much colder. I thought I had it fixed. But when I disconnected the hose, the shrader valve started to leak, so badly that you could easily hear it hissing.

Not knowing what to do, and not having a replacement valve, I put the blue plastic cap back on, hoping that it would hold the pressure. An hour later we got on our trip, but by then it was blowing totally warm.

Feeling disappointed, I was relieved to find an AutoZone in the next town. They had replacement valves, but the guy said that if I replaced the valve, I would get air in the system and would need to pull a vacuum before recharging it.

Since I was talked out of replacing the valve, I decided I would put a new can of refrigerant, and leave the charging hose connected but with the screw valve closed. That's what I did.

This time, when I connected the hose it read 0 psi (granted the gauge was basic and did not go any lower than zero). After emptying the can, it read 20 psi at 85F, and was blowing somewhat cold air. Not wanting to overcharge the system, I called it good.

We continued the rest of the trip with the hose dangling from the valve, and acceptable air conditioning for my family.

Now, I need to replace the valve, but my questions are:

1. If I remove the hose, I will probably lose all pressure before I can even replace the valve. Should I get one of those tools to replace valves while they keep the pressure?

1. Did I do any damage by leaking all the refrigerant, down to 0 psi? Did I get air into the system?

2. Could my original leak have been the valve, or did I just damage it during my recharge?

Your thoughts?

Thanks.

94RX-7 on Fri June 14, 2013 3:23 PM User is offline

Quote
Originally posted by: Pilotando

1. If I remove the hose, I will probably lose all pressure before I can even replace the valve. Should I get one of those tools to replace valves while they keep the pressure?



1. Did I do any damage by leaking all the refrigerant, down to 0 psi? Did I get air into the system?



2. Could my original leak have been the valve, or did I just damage it during my recharge?


1. You need to evacuate the system, replace the valve core, and recharge with the factory specified quantity of refrigerant. You have an unknown quantity in there right now, and it may cool well, but it may be off from the factory spec and damage can result if you're over or under. Only way to know for sure is to weigh it in. The tool to keep the pressure while you replace the valve core is a waste of money since you need to evac and get to a known, correct charge level.

1. (But actually 2) Your guess is better than mine, since I'm stuck behind a keyboard.

3. See previous answer.


mk378 on Fri June 14, 2013 5:06 PM User is offline

Quite possible there is a leak somewhere else. Look around for dye. Wait until it is dark then use a CFL "blacklight" bulb in your shop light. If the SUV has dual air (front and rear), leaks in the lines that go under the floor to the rear unit are common.

Anytime there has been a leak down to zero, the system should be evacuated before recharging. Some parts stores rent the vacuum pump and gauge manifold you will need.

Edited: Fri June 14, 2013 at 5:09 PM by mk378

Pilotando on Fri June 14, 2013 6:12 PM User is offline

Thanks for the quick replies.

I'll get a UV light and look for the leak. Then, depending on my findings I'll decide whether I can tackle the repair myself or not.

It's good to know I can rent some of the tools. (I wish I could rent the knowledge to use them also.....)

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.