A/C Problem
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A/C Problem
I finally finished installing the A/C in my 86 F-150. The problem that I have now is that the compressor is cycling too much.
At idle, there is no problem, the low side runs at a steady ~40psi.
When the motor is running above idle, the pressure drops quickly until it reaches about 25 where the pressure switch shuts off the compressor. When the compressor is off, the pressure builds quickly to about 45, then the compressor turns on and the cycle starts again. Each cycle is takes about 5 seconds.
I'm thinking that the orifice valve is partially plugged. Anybody have any ideas before I tear this @#$@! thing apart again???
At idle, there is no problem, the low side runs at a steady ~40psi.
When the motor is running above idle, the pressure drops quickly until it reaches about 25 where the pressure switch shuts off the compressor. When the compressor is off, the pressure builds quickly to about 45, then the compressor turns on and the cycle starts again. Each cycle is takes about 5 seconds.
I'm thinking that the orifice valve is partially plugged. Anybody have any ideas before I tear this @#$@! thing apart again???
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A/C Problem
It is a R-12 system which was switched over to R134. Is the pressure switch adjustable? What is the acceptable minimum pressure on the low pressure side?
Like I said, everything looks fine at idle, but it cycles quickly at higher RPMs.
Like I said, everything looks fine at idle, but it cycles quickly at higher RPMs.
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Joined: Apr 2000
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A/C Problem
you should have 40 psi at idle on low side and 225-250 on high side. this will vary with underhood temperature . i just got the info off of this site recently. scroll down this conference for my entry with question about stalling after ac conversion.
to adjust pressure, pull off connector at pressure switch on accumulator and you will find a slotted screw. most recommend 1/8 turn counterclockwise. ultimately it is best to put in switch for 134a.
to adjust pressure, pull off connector at pressure switch on accumulator and you will find a slotted screw. most recommend 1/8 turn counterclockwise. ultimately it is best to put in switch for 134a.
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A/C Problem
The compressor should come on until the low side pressure hits about 40 psi, then the pressure switch will disengage the compressor until the pressure drops to 25 PSI at which time the compressor will engage again till it hits 40 PSI . The low side should not run steady at 40 PSI unless the engine is at idle and the outside temp is very high, but as soon as you bring up the rpm it should hit the 40 psi cutout pressure and cycle off the compressor.
If it is cycling too fast, there are two things that can be wrong that I know of. Too little freon and or a bad pressure switch. I just went thru the former on my car 1 month ago. Plenty of freon but quick cycling.
Hope this helps. Walt
If it is cycling too fast, there are two things that can be wrong that I know of. Too little freon and or a bad pressure switch. I just went thru the former on my car 1 month ago. Plenty of freon but quick cycling.
Hope this helps. Walt
