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Discussion Starter #1
static 85/85
running, my low side is 35psi. high side does not move from static reading.

  • new txv valve
  • new dryer cylinder
I have done vaccum for 1 hrs. It held it fine. I added 21 oz. as indicated. Ac compressor comes on and runs nonstop, fans on but no cold. also, by the txv non of the 2 pipes are cold

It can only be compressor? or the valve inside it that is not serviceable. or maybe one of the tubes have some built in filter that is clogged? does the focus use txv AND orifice tube?

2016 focus rs 19,000km
 

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I have a few thoughts.

1. Its impossible for the situation you have to happen. If you've got a pressure differential and youre drawing down the low side, the high side will have to go up to some degree.
2. That being said, im suspecting maybe an AC equipment issue as far as your current issue goes. Have you tried running the AC with all equipment removed from the car? I've personally have a set of gauges bypass internally which obviously made the AC not work due to equalizing pressure.
Also, on the same topic, if your machine is severely under-filling the system then a similar situation could occur.
3. If you had a blockage, low side would travel near a vacuum high pressure would spike very high.

Try it again with the ac machine off the car and see what happens before you dig any deeper.
 

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Discussion Starter #3
I have a few thoughts.

1. Its impossible for the situation you have to happen. If you've got a pressure differential and youre drawing down the low side, the high side will have to go up to some degree.
2. That being said, im suspecting maybe an AC equipment issue as far as your current issue goes. Have you tried running the AC with all equipment removed from the car? I've personally have a set of gauges bypass internally which obviously made the AC not work due to equalizing pressure.
Also, on the same topic, if your machine is severely under-filling the system then a similar situation could occur.
3. If you had a blockage, low side would travel near a vacuum high pressure would spike very high.

Try it again with the ac machine off the car and see what happens before you dig any deeper.

thanks. its odd indeed i have no cold with machine off the car. will try adding some more but shouldnt have to. just to see what happens.

do you know if their is a built in filter in ac tube ?
376995
 

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You can temporarily overfill the system to rule out a scale issue with the machine. Typically what happens is high side pressure will go into the 200s and 300s (depending how much you overfill)with an overcharge condition which you dont want to maintain, but it can help diagnose whats going on here. You will have cool air for a short time then the charge will get warm due to the excessive pressure. Do this and see what pressure results you get.

To answer your earlier question, Typically a TXV system does NOT have an orifice tube because the expansion valve IS the orifice that drops the charge pressure into the core.
 

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Is your AC clutch engaging? I accidentally tugged on the plug thats in the cabin, drivers side footwell near the right side of the pedals (iirc.) The car wouldnt blow cold AC air, just warm ambient air (this was in the summer.) Reconnected that switch and AC was back. Probably not your issue but real easy to unplug and reseat just to rule out.

this post has a picture of the connection:

any DCT's?
 

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Discussion Starter #6
compressor engages.

no dct when I read codes with the Cobb accessport.

today I add some more r134 to check.
 

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Discussion Starter #7
added more but high side doesnt move more than 5 psi after adding 20% above indicated charge capacity.

low side 30 35 psi hugh side 90psi its 24celcius.

tried turning clutch by hand and its very hard to turn.
 
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