Superhogult

The complaint was ac system inop. I could see the compressor engagefor a split second. I found the system wave very overcharged. I pulled 6 pounds out and the system calls for 3 pounds. I put three pounds back in after a 10 minute vacuum with a leak test for another 10 minutes. The low side would drop to 5 pounds and shut off the compressor. The high side was around 250-275 and engaged the fan at 300. I thought the expansion valve was sticking and not allowing refrigerant to pass as should. The dryer looked old so I replaced it at the same time as a service. Now the low side is a little higher “10-15 psi” but still to low. The temp out off the vents read 58-60 degrees. 

2 hours ago, 1965 said:

Really I know enough to get by, I know everything needs to be clean, pull a good 30 minute vacuum. Would think low side should be around 25 to 30 & high from 250 to 280 range. Also thought engine fan was supposed to run any time air conditioner compressor was on.

The fan will engage when the ac high pressure switch closes for condenser cooling. When pressure is below the 300 the fan will not be on. 

From what I have experienced on other tractors the high side is in range but the low side pressure is very low. I usually see pressures around 40  psi. 

The blower has an issue cutting out and the relay getting very hot. I traced the issue to the selector switch on the hvac panel. But I have removed the blower and cleaned and tested the motor. The evap has a skin of ice on one side looking at it with the panel off. It doesn’t freeze up solid but it does form on the copper tubes on the side of it. 

Also before I put the expansion valve in the low side would drop down to 5 psi and the compressor would kick off. Now it runs none stop at 10-15 psi and has a wiggle in the gauge reading.  Not sure if that means anything 

Ok I will check the radiator assembly as well as evap. Will the evap have some ice on it while running or should it be cold and wet? 

The high side pressure climbs to 300 and the fan kicks on and the high side immediately drops to around 150psi. Isn’t the an indication of good air flow across the condenser?

What about the very low low side pressure? 

Hey all I have a 99 ch613 I’m trying to get the ac right on this thing. While at 1k rpms the evaporator will start to freeze up. The high side pressure is around 275 and the low side keeps dropping to around 10psi I just changed the expansion valve and dryer. Could I be looking at a plugged evaporator?