AC blowing warm air

[emdoller]

It's been a while since I used my AC but it is blowing hot air.

I've fixed many AC systems on old Chevrolet cars that used R12 and understand the fundamentals. My NSX is a 95 and has r134.

My questions:

1) should I simply try adding more r134 and see what happens?
2) do I need to jump the low pressure switch to add it?
3) should I simply follow the standard r134 temp vs pressure curves?

Or

4) should I pump the system down and start fresh adding the proper r134 by weight?

Ed

 

[nigel]

Option four !
Replace the Filter / Drier as well.

Cheers
nigel

 

[emdoller]

Option four !
Replace the Filter / Drier as well.

Cheers
nigel

Thanks. That's what I thought. I'll check the low and high side pressures before I pull it down just to see where I'm starting from. I'm not worried yet that there's a serious leak as the car is 22yrs old and has never had an AC issue. I'm surprised it lasted this long. I'll order a new dryer as well.

Ed

 

[nigel]

You need to replace ALL the o-rings in the system so they will hold the higher R-134 pressure.
Not to worry, they're not hard to get to.

Cheers
nigel

 

[mastaf]

My AC was also blowing hot air. So after performing various tests, they had to take the dashboard out. please, see the clogged arteries and lungs of the system with your own eyes.

 

[robertcope]

Well, that's horrifying.

 

[mastaf]

I know. :redface:
I wonder if I need to do some other things while the dashboard is already out there.

 

[emdoller]

To close this out, I measured the pressures of my low and high side and they seemed ok. I then played with the CCU and determined it would only blow on high. Took out the board and sent it to Brian K. He had it back to me in three days and the system is working fine.

Ed