Low Side Pressure High But Cools WELL!

[tperk1000]

04 F350 Diesel

Had a leak...replaced O ring at evap / accum connection ..fixed leak.

At same time decided to replace orifice with next smaller size. Old orifice was extremely difficult to remove ....probably because it was installed BACKWARDS! .....by yours truly about 4 months ago.

Put all together, evacuated and charged by weight. Now low side pressure at 75 ambient is 100 psi....about double what is should be. Ford diagnostic procedures suggest that the orifice o-rings are missing / defective. There were definitely o-rings on the new orifice.

What is really baffling me is that the vent temperature in the cab is 38 DEGREES!!!...so the system is cooling well.

Sooooooooo...do you think I have anything to worry about? My tendency is to let it ride.

[Nacho]

Is your lowside properly connected and coupler secured?. Try rotating a secured low side coupler and see if the gauge reading drops. It is not possible to have a 38°F vent temperature with a suction pressure of 100 PSI. You have a gauge problem.

[tperk1000]

Thanks,

My gauge set is old and I have to fool with it constantly due to bad seals and a defective cut off valve on the high side. Although I am pretty confident that the low side is 100 psi (because the gauge returns to exactly zero when disconnected), I am going to buy a new gauge set and see what it says. Vent temp is definitely 38 degrees.

Hopefully you are right and the low side reading is incorrect.

[lanceman73]

Nacho on the right path. It's that or your schrader valve isn't working properly.