Refrigerant not being pulled in - please advise

[LunarFox]

Hi all,

I just joined this forum hoping to get some help with an A/C recharge I've been working on the past few weeks. The vehicle is a 2001 Mazda Protege 2.0L.

It was completely evacuated so I could remove the the evaporator unit to fix a cracked body seam behind it, and now I'm having problems recharging the system.

I started out by pulling vacuum down to -29 inHg for over an hour, and it held overnight so it doesn't appear I have any leaks. I hooked up a can of R134a and purged the line of air, started the engine with A/C on and opened the Low side port to start filling. Pressure jumped up to ~70 psi and stayed there, but compressor wouldn't engage. After consulting the service manual, Mazda recommends filling half-way (300g of 600g total) through the High port with engine off first, which I was able to do by putting the can in warm water to help the refrigerant flow in. This was enough to get the compressor clutch and fan to engage, but even with compressor on I can't get any refrigerant to flow in through the Low port. The compressor clicks on and off sporadically and the High gauge climbs up to ~110 psi, at which point the compressor stays on for good, but the Low side pressure doesn't budge and refrigerant doesn't flow in. I tried putting the can in warm water again to help the gas move but that just increased the Low side pressure to around ~110 psi as well.

That was hours ago, and now that the vehicle has been off for some time both gauges read ~65 psi or so.

What's going on here? Why are both sides reading the same values?

Something appears to be stuck somewhere, either in the open or closed position, I don't know A/C systems well enough to make sense of it. Possibly a faulty expansion valve? Clogged condenser? Broken compressor?

Please advise. Any and all help is appreciated!

[Dougflas]

Sounds as if the low side hose connector is not connected into the system. Remove the gauges and bleed them. Make sure the hand wheels are closed. Connect the low side to the system. Do you have pressure? You should see a static pressure.

[LunarFox]

Yes, there is static pressure being read by both gauges. The connectors are engaged, I'm sure of it.

Both sides read the same, around 55 psi at the moment. It's around 50°F right now.