Couger1968
Dazed and Confused
What pressure should I set my AC low pressure switch. It is adjustable, I am retrofitting 134a. Thanks
AC pressure switch
- Thread starter Couger1968
- Start date
Don W.
Stab it and steer it
Re: AC pressure switch
Funny, I just found this out doing the conversion a few weeks ago. We had a machine hooked up to see the pressures. Don't ask the numbers, sorry. (70 low 140 high? can't remember) What I did was to back out the screw two turns. Oops, didn 't work. Back in 1/2 turn, perfect. Watch the compressor clutch. At idle (not sure if that matters) AC on full cold, high fan, compressor should run about 50% of the time. Key word "about." But that's where I ended up and it works great.
Initially the clutch would just cycle on and off. That screw did the trick.
HTH
Funny, I just found this out doing the conversion a few weeks ago. We had a machine hooked up to see the pressures. Don't ask the numbers, sorry. (70 low 140 high? can't remember) What I did was to back out the screw two turns. Oops, didn 't work. Back in 1/2 turn, perfect. Watch the compressor clutch. At idle (not sure if that matters) AC on full cold, high fan, compressor should run about 50% of the time. Key word "about." But that's where I ended up and it works great.
Initially the clutch would just cycle on and off. That screw did the trick.
HTH
Couger1968
Dazed and Confused
Re: AC pressure switch
I read somewhere 20-21 psi for conversion. I also tried using a variable orifice tube, and don't think its going to work.All it does is cycle on and off, doesn't cool at all. I turned pressure switch so the pump stayed on a little and my pressure dropped to 0. When it clicked off it would raise. I think I am going to have it switched back to stock. I could be the wrong one ,but it was the one rock auto said. I accidentally over charged it anyway with 36oz . I thought I had the can turned off. I was told to use 32.
I read somewhere 20-21 psi for conversion. I also tried using a variable orifice tube, and don't think its going to work.All it does is cycle on and off, doesn't cool at all. I turned pressure switch so the pump stayed on a little and my pressure dropped to 0. When it clicked off it would raise. I think I am going to have it switched back to stock. I could be the wrong one ,but it was the one rock auto said. I accidentally over charged it anyway with 36oz . I thought I had the can turned off. I was told to use 32.
Don W.
Stab it and steer it
Re: AC pressure switch
The amount of refrigerant should be on a sticker somewhere. I was just saying what worked for me. The pressures I mentioned would be system pressures. I don't see how you could have 0 unless the system is empty. Pull the system down (recycle) and remove the expansion tube, It's in the lower smaller line going into the evap. Should come out with a pair of pliers. There is a screen with it, check that it's clean.
The amount of refrigerant should be on a sticker somewhere. I was just saying what worked for me. The pressures I mentioned would be system pressures. I don't see how you could have 0 unless the system is empty. Pull the system down (recycle) and remove the expansion tube, It's in the lower smaller line going into the evap. Should come out with a pair of pliers. There is a screen with it, check that it's clean.