Tractor A/C pressures R134a

[alldodge]

Trying to determine the correct pressures for my Kubota M9540 tractor. The cab filters are clean and so is the radiator and condenser. Looked into the duct work and the damper doors look to be working correctly, and it does go into cab air recirculate.

Pressures on a 85+ degree day is 50 psi on the low and around 250 on the high at idle. When the rpms go up, the low side goes down maybe around 30 and high stays about the same.

Air is cool but never cold, and on a hot day, it gets way to warm in the cab.

Anyone think the pressures are ok?

 

[Scott Danforth]

your pressures are right where they are supposed to be at 85 degrees, maybe a touch low when you bring the RPM's up

http://acprocold.com/faq/r-134a-system-pressure-chart/

 

[alldodge]

That's the chart I was using, still not cooling well. I poster on Orange Tractor Talk posted a link to the work shop manual and its fairly close. Shows readings to be taken at 1500 rpm and low (21 to 28 psi), high (185 to 242 psi)

Don't know but the caps were missing when I bought the tractor so someone has been messing with it. They may have induced some air in it. Hope I don't need to evacuate, vacuum and recharge