I'm sure our air conditioner is leaky. There is some dried out dye around the service port. It cycled way too fast so we went to look at it.

Reading the volvo documents it seems they want to rely on empty, vac and fill several times for every procedure. I do not have the ability to recycle the gas at home so there must be another way.

90 psi static pressure and when it cycled on it went down almost to vacuum then clicked off.

So we added two 12 oz cans and it's kind of cool now at 45psi but something still wrong.

Before I add another can I wonder how I can see the high side pressure. Then I learned that the sensor on the condenser should report the high side pressure to the engine control. I should be able to use obd2 live data or VOL-FCR to see this parameter while the engine runs. Has anyone used this and was it useful?

If we have to open it then I will look first at the expansion valve. I have no idea how the dye residue got on the service port and don't know if it was from a professional or the "GAS + DYE + LEAK SEAL GLUE" in the can at walmart. If there is glue in there then maybe it is stuck at the expansion valve. We can hear it hissing for a minute after shutdown as the pressure equalizes and i've never heard one so loud before.

But I think I need to see the high side pressure, I think we put 650 grams in it and the capacity is around 900 or 1000. I want to check this out before dumping more gas in.

 

The only way to do this right is to evacuate the system and let the air pump pull a vacuum. See if you can hold a vacuum. If not, you have a leak, likely the evaporator core.

Pushing gas in it does not solve the problem. The leak will get worse. You'll have to remove the dash. Good luck.

 

Hey Tony. I ended up using the VOL-FCR software to read the high side pressure through the ECU. The A/C still works since I did the "top off" nonsense six months ago.

I will start a leak diagnosis whenever it needs gas again. This month I just fixed the vacuum solenoids so the air conditioner should be available all the time. We will see when the season turns warm.

Someone has taken the evaporator apart before, they did not replace the foam seal at the firewall. If I take it apart I am going to replace all the rings and other seals too.