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Discussion Starter · #1 ·
I tried getting my vintage air to cool. With no luck yet,
Have been talking to the tec from vintage air and hasn't been able to figure it out yet. Everything runs but lowest it has been is 64 degrees. 134A system-- Gen 4 The low side reading on the manifold guages for compressor are -35 and the high side is+40. A good A/c guy told me it was the expanson valve.

Does this sound right???? Signed Ivan Confused
 

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Trifive Automotive Electrical Wiring Expert
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I tried getting my vintage air to cool. With no luck yet,
Have been talking to the tec from vintage air and hasn't been able to figure it out yet. Everything runs but lowest it has been is 64 degrees. 134A system-- Gen 4 The low side reading on the manifold guages for compressor are -35 and the high side is+40. A good A/c guy told me it was the expanson valve.

Does this sound right???? Signed Ivan Confused
Need more info. How long did you vacuum it and how much freon did you put
in? High side way too low. Sounds like a blockage. Is the dryer plumbed i the correct direction of flow? Is the condensor installed upside down? Does the compressor continue to run?
Yes, it has an expansion valve.
 

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VA recommends 6-12 on the low side but everyone else says 20-40. The high side should be 2 X ambient temp + 15 to 20%. Your #'s sound way off, how much Freon did you put in?
I have been fighting a loud growl for months and have done a pantload of reading on these systems. No success yet, for me.
 

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Low pressure on the high side suggests the expansion valve is wide open or failed. if it was blocked it would have excessive pressure. are you sure the compressor is coming on.
 

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Low side - 35 that is in a vacuum. You have a restriction some where or, you do not have enough freon in it. Most of the time the restriction is in the expansion valve. :anim_25: bowtie-trifive :gba:
 

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Discussion Starter · #6 ·
VA not working properly

I have checked all the pressures high and low as recommended And the low side is way to low. Seems like a restriction or bad expanson valve. freon is not going threw the system as it is sappose to. Everything is hooked up right.
Had a repair garage that does air put the freon in, 28oz. as called for. Never has worked since installed. The high side levels out quickly when air and vehichle is shut off, but low side takes about 4 to 5 minutes to level out.
I believe the system is clean with no contamenents in it. I will be having the system evacuated tomorrow to check out the loe side of the compressor to make sure it has vacum. Ivan
 

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-35 on the low side is impossible.

A pure vacuum is -30" of mercury or -14.7 psi. If you are at sea level.

What is the pressure when everything is shut off? S/b 80-100 psi high and low.
 

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I have checked all the pressures high and low as recommended And the low side is way to low. Seems like a restriction or bad expanson valve. freon is not going threw the system as it is sappose to. Everything is hooked up right.
Had a repair garage that does air put the freon in, 28oz. as called for. Never has worked since installed. The high side levels out quickly when air and vehichle is shut off, but low side takes about 4 to 5 minutes to level out.
I believe the system is clean with no contamenents in it. I will be having the system evacuated tomorrow to check out the loe side of the compressor to make sure it has vacum. Ivan
I just installed my Gen 4 system in my 57 and it took me 3 times of evacuating and re-charging the system to get it too function properly.

As far as i am concerned the 28.8 oz that V.A. recommends is incorrect, now it might be because my hoses are shorter or god knows what, but the first two times i installed the 28.8 OZ they recommend, the system was over charged and the pump would just cycle off & on because the pressure was threw the roof on the system.

The third time i installed two 12 OZ cans and just a kiss from the third one and my Low & High pressures were just about perfect and she blows cold air at 41-43*'s

Sounds like you may have a different problem, but just wanted to give you the heads up on the 28.8 OZ being to much for my system.

Here is a link to the hell i went threw trying to get my A/C working correct for a week straight..... http://www.trifive.com/forums/showthread.php?t=108780

:anim_25:

Rick
 

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Just a couple of thoughts for you...freon is a DuPont trademark name for R-12 and R-22. The new refrigerants are isecon trademarks R134A etc... If you have low high and low low side while compressor is running...either compressor is not creating a dif (no pump) or...the TXV is wide open...you can check this with a thermometer in the Evap and one on the suction line at the compressor. See if there is any superheated vapor. If not...TXV is not creating a low side.

Other than that...use the TP charts and manufacturer recs for the system and the refrigerants used.
 

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Discussion Starter · #11 ·
not cooling properly

reply to Rick L. When I got the - 35 on the low side it was because the guages I use have 4 settings on them .. I wasn't reading the mercy chart but the 134A numbers which the man from Vintage air ask for.
 
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