AC Charge Problem (High Low, 0 psi High)

[adamj]

Really stumped here, looking for some tips and advice on getting my ac working.

Here's what I've done:
- new compressor
- new evaporator + orifice tube
- new condenser
- new accumulator
- new r134a adapters
- lines flushed with ac flush
- new o-rings all around
- rear evaporator flushed, replaced TXV
- measure oil added to each component, ac compressor turned and lubricated prior

I pulled vacuum for an hour and let it sit, no leaks.

So everything is brand new and clean.

When I went to charge the system after pulling vacuum, I got low pressure building on the low side, but the high side would not change, it stayed at 0 psi. High side would not budge, so I added another can and still nothing. I am adding to the low side port and the compressor is engaged properly.

Any ideas? What's wrong, bad compressor? Some blockage?
From what I've read, a blockage would have a very high high-side pressure, haven't seen much info on high low and low/0 high.

 

[foamypirate]

I would lean toward a bad compressor if you aren't making any pressure on the high side. If left alone, do the low and high side equalize to the same pressure?

 

[adamj]

I was afraid it might be a bad compressor, but it is brand new from Four Seasons, and it's not a reman unit, so I am skeptical on that, but it could be possible I guess. Any other way to test the compressor is working properly?

If left alone, the low and high sides do not equalize, does that throw a red flag for something?

 

[foamypirate]

Yeah, the high and low side should be equalizing when left alone. It seems odd that the compressor would engage and not create any pressure on the high side at all. Now that I'm thinking about it, are you positive your high side gauge is working? Maybe it's just a bad gauge set. You can always do a "feel" test on the high side while the compressor is engaged. If the discharge line from the compressor to condenser is hot, then the compressor is probably working fine, and you have a bad gauge.

 

[adamj]

Ok, I have access to another gauge set, I will compare the two.

 

[yevgenievich]

What are low side pressure when compressor is on vs off? If it starts high and the drops down then high side should have pressure going up

 

[bucket]

I agree that it sounds like the high side gauge is simply not reading. How many cans were added? It's going to hold around 4 lbs of r134a, so if you only got a can or two in there then it's not going to get cool at all.

It's also very important to make certain that your clutch fan moves plenty of air at a hot idle.

 

[adamj]

Just to close this out, the problem turned out to be the compressor. I bought a new one again (different brand this time) and I now have cold air!

 

[74 Shortbed]

Glad to hear it all worked out..

 

[Cuba]

Glad to hear it worked out also... but even more glad you came back to close the thread!! lol

 

[Honky Kong jr]

Sweet!