A/C compressor always running

[edboyce1971]

I have an 87' 4.0 renix with an A/C that has been converted to 134. I replaced the compressor, drier, hoses, expansion valve and had both coils leak tested. Flushed the system and put a vaccum on it and charged to correct pressure. I works and blows fairly cold but the compressor does not cycle on and off it pretty much just stays on. Also I feel like it should be colder. What controls the cycle of the compressor? I think it might be crapped out.

[90xj06]

i don't think its supposed to cycle on and off. there is a valve that regulates the freon so it don't freeze over. was the new parts for r-134a if not it was because it was designed for r-12 it wound be as cold using r-134a.

if the compressor cycled on and off before it was because you where low on freon.

[edboyce1971]

All of the parts I bought were for 134.

Ed

[langer1]

It is cycled by the low pressure switch the switches are different for R134a and R12 because the pressures are different.

[90xj06]

yes they are. r-134a run higher psi than r-12. but he said that all the parts where for r-134a so i would imagine the switch is. isn't it mounted to the drier?

[90xj06]

apparently your supposed to vacuum out the old r-12 but i said screw it if it works it works. and it gets coooold.