4430 ac

All,

Put in new lines through cab and some under cab 3 years ago. Also, new expansion valve and dryer. Vacuumed and put in 134a. At same time a thermal switch. Has been working fine for 3 yrs till recently and now the compressor will not kick on.

Not having gauges on hand I tried adding 1 small can r134a from walmart from just the pressure in can. . Still no luck with compressor coming on. That was attempted with tractor running and cab fan and cab ac switch on. Also, had the compressor manual valve open for low side.

Have checked continuity between b and c on thermal switch and it has continuity. Tried a new spare thermal switch and it did not start compressor either.

With key on, fan on, and ac switch in cab on there is 12 volts showing as coming in to middle c wire where thermal switch plugs in.

I tested compressor clutch by jumping to battery and it comes on.

Took a gamble and added 1 can of freon by jumping clutch to battery. Then shut manual low side valve. Then put thermal fuse back in. Compressor still does not kick on.

Question: could these be 2 bad thermal switches showing good continuity between b and c?

ANY GUIDANCE WOULD BE APPRECIATED.

Start checking where you are loosing the power,,The yellow wire in front of the upper right side of the radiator is the compressor wire, unplug it and check for power,,then check the yellow wire under the fight front corner of the cab...sort of seeing what you have and what you don't have, there is a pinch point where the wire comes past the left side of the radiator, they pinch in between the ac lines,, I re-route them under the radiator plate to get away from that pinch zone...

If you have 12 volts coming in it should work assuming the thermo fuses are good . Look at the bottom of the fuse to see if there is a bump on it . If it does then its no good .

There is 12v at the middle wire where thermal fuse goes. It is the b wire, think I erroneously called it c earlier. So it looks good to there.

The new thermal fuse looks fine, don't see a bump, and continuity shows good. The old thermal fuse Also shows continuity, it has no bump, but does have a slightly darker place in middle bottom. Again the new fuse 'looks' fine.

Well if you have 12 volts there it must be the fuse, or connection,,or a ground problem....I have thought about wiring a low pressure limit switch into them, but they are pricey,,that fuse thing they use is not a good idea..

AP Air offers a "compressor clutch saver relay kit". Have found wiring on some tractors being old and poor connections don,t send enough amp's to click clutch on. Since you have juice down to your fuse and can hot wire clutch, I suspect you have a voltage/amp problem.
Automotive parts stores have relays and harnesses also and you tube shows how to wire them.

I want to get hooked up with AP air,,The Deere AC parts are getting to be unreasonably high..a friend of mine that use to work Deere parts said that they got most of the AC parts from AP air...then marked them up to the Deere price, said it made them much more money on the parts.

If you need contact info my email is open. They have a extensive inventory on all makes and very good quality.

not sure who handle ohio but the guy who is the dist. for ag-parts also handle ap-air call ag parts at 800-445-6698 they well get you to right dist..