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Discussion Starter #1
ok, heres a question for you ac wizards. AC not working and thought it needed a charge, plugged onto the low pressure side and it said 130 psi. Bleed the pressure off to 110psi and started swather, pressure slowly started to build. So do I have a low pressure switch that pooched?

Hehe help!!
 

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Im assuming the engine was running, AC on? What do you mean slowly started to build? Higher than 110?

Does it work at first startup and then stop working, or never works? Intermittant or nothing ever?

Can you hear ac compressor click on with it not running and keying it on?
 

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Discussion Starter #4
Ya the condenser never comes on. Bled it down to 90psi then started engine, it slowly started to build. Had a low pressure switch go on the tractor once wondering if its the same thing.
 

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I edited my post, said condenser instead of compressor i realised.

Engine off pressure dont tell you much, outside of letting you know theres no major leak.

Forst you want to see if the compressor will click on without it running. Just key it on, and turn ac on and off (fan must be on) and have someone stand next to it and hear for the clutch engaging and disengaging. If nothing, you have a switch, wiring, or compressor issue.

If you hear the click, but compressor does not come on when running right away, then yes probably a pressure sensor-low or high. If it comes on until you get warm and then cuts out, dirty condenser.

Im not familiar with that tractor, but some newer deeres also have a evaporator frost sensor that will shut it down when bad.
 

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The low pressure switch will only stay open if the pressure is to low on the suction side. There is a high pressure switch on the other side that will stay open if pressure to high. You can pull the plugs on these sensors and put a jumper wire across the connection. Bear in mind that these are safety switches and would only do this in trouble shooting. Not saying there was an over charge of Freon but you would likely find 130 psi on both sides of the compressor if it is not running. You should see the low side drop as the compressor cycles. If it doesn't cut in I would say there is a temp control switch, open or shorted wiring or fuse blown to the compressor clutch or bad compressor clutch. If you can see or hear the compressor cut in I would strongly guess the pump is failing or failed if the low side pressure doesn't drop. Air in the system will also keep the low pressure side high with little or poor cooling. This has been my experience.
 

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Discussion Starter #7
yup was the low pressure switch
 
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