A/C questions

[meatloaf]

My AC had stopped cooling... yesterday I pressurized it nitrogen, leaked checked, pulled a vacuum & then filled with oil and 2.5 cans of Freeze12, but if does not cool... compressor does come on, etc.

I was in a hurry when I was doing it so I did not spend a lot of time diagnosing. I was noticing that after I would put in a can of refrigerant, the pressure on the gauge would go up and then would start to drop to a vacuum. Why? The low side is the bigger diameter hose, and the port is a few inches away from the compressor, correct?

Truck= 92, 22RE

Did I miss something?

Thanks in advance,
ML

 

[Michael Hanson]

The compressor has marked on the case hi and lo incase someone has modified the hoses or colors. Does that help? MIke

 

[meatloaf]

No mods, I've had this truck since new...

 

[Michael Hanson]

Why freeze 12? Did you flush the system first or just pull a vacuum?

 

[meatloaf]

Freeze12 was the only this I could find at a reasonable cost and no I did not flush. I thought that freeze12 and r12 were compatible? I did run a little nitrogen first and then vacuumed.

 

[Michael Hanson]

You are probably better at this than me,but I hear good and bad about freeze 12. My a.c. supplier in Irving always recommends a full flush when changing between 12,-freeze and 134a.Also changing out the dryer too. Just a thought. MIke

 

[meatloaf]

I am no better... Do you know how to or what to flush it with? I do have a new filter/drier whick I have not installed. I was thinking of doing the r134 conversion but figured I'd try the freeze12 idea first...