JD 3720 Air Conditioning line pressures?

JDneophyte · Aug 2, 2012

Well.......we're still good with the new "maintenance" required after every mow/usage. The key is blowing out the back filter and condenser after every use. As it's dry, our mows are very dusty.....so at about 3 hours of usage, it's all the system can take before needing a full clean out.

DP Property · Aug 3, 2012

Wow I am having this very problem and I have been doing lots of cutting lately so I cleaned out the condenser and that screen today with just a hose at regular pressure was afraid to blast it with a powerwasher and bend fins also cleaned airfilter several times might be time for a new one. I used to notice little water dripplets at the rear sides of where the cabin airfilter is where those two lines are on each side. I am guessing those lines are for moisture drainage but I don't notice that anymore and the ac has not felt as cold also seemed like sometimes it would feel great and then other times did not matter if switch was on ac or defrost cool air felt the same but not cold. I guess I am having the same experience that you all are having. I did not pull the battery today but will do so in the future. How do you know when your system is overheating and shutting down> and in the manual it says the ac clutch can jam if the tractor is in storage what is the ac clutch? There is a round unit to the right of the condenser it felt awful hot today is this part of the ac system? Thanks Guys.

JDneophyte · Aug 3, 2012

The round unit on the right of the condenser is the dryer (captures any moisture that is in the refrigerant lines). You can check and see if the a/c is on after turning it on in the cab, then checking that the compressor is on (you'll see it engage after turning system on). If it doesn't, then likely the system has overheated (there is a high pressure switch that automatically shuts the compressor off when the system is overloaded).

Clean every thing out (behind the battery, then behind the turbo cooler (the small silver radiator on the top of the condensor....loosen the lower bolts to get behind it with an air compressor or pressure washer on low).

This absolutely was the problems i was having.....and it took a John Deere Mechanic to figure this out. Its just a bad design on otherwise a fantastic machine.

DP Property · Aug 4, 2012

Is it normal for the dryer to get very hot?
Wow you guys were not kidding I had already cleaned it when I pulled the battery, thank you for all the help got to love this forum!