AC pressure switch question. (1 Viewer)

[ROFF]

With all the AC woes I decided to just replace everything. Started out with a low charge of R12, then the expansion valve clogged. Found a bunch of gunk in there. Then evidence of a leaky evap. Ive been down this road before. Replacing little crap until eventually it would have been better to just replace it all. So thats what I'm doing. Replacing all but the hoses which are fine.

Ordered it all from Coolstream, they are super helpful so big thanks to them.

So about the pressure switch, Ill grab one from Toyota but is it dependent upon refrigerant used? Its R12 now but may or may not go with 134. Does it matter with the pressure switch? Probably just needs a bit of pressure right?

Thanks
Brandon

 

[flintknapper]

With all the AC woes I decided to just replace everything. Started out with a low charge of R12, then the expansion valve clogged. Found a bunch of gunk in there. Then evidence of a leaky evap. Ive been down this road before. Replacing little crap until eventually it would have been better to just replace it all. So thats what I'm doing. Replacing all but the hoses which are fine.

Ordered it all from Coolstream, they are super helpful so big thanks to them.

So about the pressure switch, Ill grab one from Toyota but is it dependent upon refrigerant used? Its R12 now but may or may not go with 134. Does it matter with the pressure switch? Probably just needs a bit of pressure right?

Thanks
Brandon

Hi Brandon,

I am not familiar with the 60 series but I do know a little about A/C systems. I would highly suggest you flush your lines before reusing. You are correct to replace the other components. Many folks learn this the hard way....so you are certainly not the first.

If it were me...I would not convert to R134a. R12 is going to work better in your system and while it is fairly expensive...the refrigerant is still available from certain online sources..(though you are supposed to be certified to purchase it).

As concerns pressure switches (I believe your model Cruiser has high and low pressure switches as opposed to a single binary switch) but either way you are fine using R12 or R134a. Pressure is pressure. It's just that R134a has a greater specific volume than R12 so you would use about 80% the capacity of R12 if converting.

But the switch(s) would work the same. IF the system falls below about 25-30 psi the low pressure switch will cut the compressor off. Alternately...if the system reaches about 380-400 psi (a rarity) the high pressure switch will cut the compressor off.

IF you happen to have a single switch...it would be binary switch which simply provides both functions.

Good luck with your repair.


Flint.

 

[ROFF]

Thanks Flint. I will probably keep it R12, I have some still but I will use r12/r134 oil in case I do switch it over. We may be heading to warmer climates so I figured I better replace the whole system and have some piece of mind. Dont mind not having AC most of the time, but when going to work in work clothes, its sucks.

Ill be grabbing a pressure switch tomorrow hopefully.