Date: Mon, 6 Jul 2015 00:15:54 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: My A/C Saga Continues...
In-Reply-To: <CAE_mVa2vZQYFTHSsYrmfFo0=i34MuQT9wZTYPW4v=rVS9B7E8w@mail.gmail.com>
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What volume of refrigerant did you put in? Your readings could also be due to an undercharged system. What type of expansion valve do you have? Is it the four port or an two port with a feedback bulb and capillary tube? All AC guys know not to pressure check or introduce common compressed air into a refrigeration system. Lots of moisture. Receiver dryer now garbage. Nitrogen is the test gas of choice. Moisture in the system can cause ice crystals to form near the expansion valve. Blockage, over pressure broken compressor valve parts.
Now you have refrigerant in the system and you may need to open it up. Do you have recovery equipment? Intentional release to atmosphere!
Replace the expansion valve and dryer and bring it to a qualified shop for testing, evacuation and filling. Consider upgrading pressure switches and controls to get full radiator fan operation based on high side pressure demand. Radiator fan on low speed only will not give good cooling with van not moving or at low speeds.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Michael McSwain
Sent: Sunday, July 5, 2015 11:39 PM
To: vanagon@GERRY.VANAGON.COM
Subject: My A/C Saga Continues...
So So close, but no cigar.
Wanted to see if my theory sounds reasonable to anyone who knows more about this than me.
So I finally got this old Behr system put together today. I flushed the system, sprayed compressed air through to get as much of the flush out or evaporated, put it on a vacuum and let it sit for 3+ hours until I was convinced there were no leaks, and finally began charging the system.
Because of some rust and a previous owners trigger happy spray painting I was advised by a friend to leave some of the o-rings be, but I did replace them at the compressor and dryer.
Our disappointing results were as follows:
Too much pressure on the high side, a little over 200 while running.
Too little pressure on the low side. Pegged at zero while running. One part that I didn't replace, (kicking myself now because several people mentioned that I should, including some on this list), was the expansion valve.
So the theory is that if the expansion valve was plugged or gunked up, the compressor would eventually suck all of the refrigerant out of the low side and pump it into the high side and with no way to flow through the system and back to the low side I ended up with too much pressure on one side and a vacuum on the other.
I'm thinking that a clogged expansion valve be the most likely culprit.
I'm new to this, but does that sound about right?
--
m.
