Brand new setup, compressor not sucking down

[texas240]

New here trying to figure out my a/c system. I have a 1993 volvo 245 with a 2004 chevy Lsx v8 swap. I am using a brand new Acdelco compressor that is used on this engine.

New parts:
A/C compressor
Condenser
Dryer
orifice tube
new hoses from the condenser to compressor
7oz of PAG 50 that came with the compressor

Used:
Original Evaporator
Pusher fan
Volvo 960 radiator puller fan

The issue at state is that the system is not sucking down any freon. I am jumping the compressor switch at the dryer to get the compressor to come on and I have a base idle of 1200 rpm when doing this. I have flushed the system a handful of times, no blockages. Hard to think that a new compressor is bad but I was able to vacuum the system down to 30 hg and hold it there over night.

Any help or advice is greatly appreciated it.

[bohica2xo]

Did you pull a vacuum on the system before charging?

[GM Tech]

I'd guess from here that you have a valve on your can or gage set not opened-- "sucking down" is tough to decipher-- I'd say a suction pressure of "xxx" may be easier for us to understand-- it won't suck down while charging- it will actually show positive pressure of 50-60 psi until can is empty- then drop to about 30 psi when operating....

[texas240]

I'd guess from here that you have a valve on your can or gage set not opened-- "sucking down" is tough to decipher-- I'd say a suction pressure of "xxx" may be easier for us to understand-- it won't suck down while charging- it will actually show positive pressure of 50-60 psi until can is empty- then drop to about 30 psi when operating....

System won't suck any thing from a can. Im getting 110 psi at the low side and 0 at the high side but I can't get the system to actually take any freon into the system as a whole.

I hope that makes sense

[texas240]

Did you pull a vacuum on the system before charging?

Yes

[mk378]

Zero on the high side suggests that one or both of the manifold hoses are not coupling to the car properly. Any pressure you put in the low side should blow through the check valves in the compressor and appear at the high side even if it is not running. Some couplers have a knob on the top that must be turned to open the shrader valve after coupling to the car fitting.

When you evacuate, at first only open the high side valve to the vacuum pump. Watch for the low side gauge to go down. This is pretty good proof that you are actually connected to the car and evacuating it rather than just evacuating the manifold. Then open both valves and let the pump run for a while to develop full vacuum.

Start the charge as liquid with the engine off. This will put enough pressure in to close the switch so that you can complete the charge as gas through the low side. Jumping the switch is not necessary or recommended since it leads to running the compressor dry.

Edit: Also since this is a custom build, consider the possibility that the compressor is plumbed in backwards-- i.e. suction port connected to the high side.

[bohica2xo]

The first step with a system in vacuum should be adding as much of the charge as you can - as liquid with the engine off.

Jumpers sell compressors. Running a compressor with no refrigerant in the system for half an hour is often the end of it.

Sounds like you have service coupler issues - the system may not even be evacuated properly. You should deal with the coupler issue first, then evacuate the system and start over.

[texas240]

The first step with a system in vacuum should be adding as much of the charge as you can - as liquid with the engine off.

Jumpers sell compressors. Running a compressor with no refrigerant in the system for half an hour is often the end of it.

Sounds like you have service coupler issues - the system may not even be evacuated properly. You should deal with the coupler issue first, then evacuate the system and start over.

That was one of the first things that we considered a possible problem, second was maybe a faulty orifice tube. Haven't had a chance to actually do anything today. Hopefully tomorrow I can put these good thoughts, ideas into use and get some answers or closer to the answer then a solution.

[texas240]

PROGRESS!!!!

Did the following steps as a few members told me. After fidgeting with the low side quick release fitting on the low side fitting I was able to get it to work on my other set of harbor freight cheapo gauges/manifold. Put 12oz of freon in and started the car then put another can in equalling 24oz then some where around 2-4 more ounces in. I was able to get the temps from the vents down to 59º but no cooler. When I give the are some throttle the air coming out of the vents warms up to whatever they feel like getting.

Low side pressure 55psi
high side pressure 400+ish

High side seems rather high to me.

Any ideas?

[GM Tech]

Mist the condenser with a garden hose- if pressures come down , you have an air flow across the condenser issue- as in blockage or bad fan or fan clutch.