AC blowing warm air

1996 Riv AC is blowing only warm air. Clutch seems fine and not sure how to proceed to fix problem, short of taking her to an air conditioner shop. Is there a write-up and if so please give link. Thanks for any help!

its probably one of the hvac vent actuators. There are 3 units under your dash on the center column. There are a lot of posts about it on this forum. usually a gear or motor goes bad and it needs replaced.

Depends if it's blowing warm in all the vents, or only on one side of car. If only one side, it's the actuator/door. If blowing hot both sides, probably the AC clutch. If not blowing at all, or cutting out, it's either the blower motor or more likely the blower control module (easy fix).

It can also be an undercharged A/C system - it tries to cool but the entire evap doesn't get cold if the charge is wrong (high or low). Even with working actuators an incorrect charge has caused lopsided cooling.

What do you notice when you change the temp from 'hi' to 'lo' (approx. 90 to 60)? Do you hear/observe the blend door(s) change?

Have a shop check your pressure or get the self-test unit and one or more cans of R134A. I've seen where the pump won't engage with insufficient pressure.

BatMobile wrote:

1996 Riv AC is blowing only warm air.  Clutch seems fine and not sure how to proceed to fix problem, short of taking her to an air conditioner shop.  Is there a write-up and if so please give link.  Thanks for any help!

The problem is it might be one of several problems.

The AC system leaks down over time as the refrigerant molecules are small enough to evap out of the hoses over time. It takes a long time, and you are about due. When this happens, the AC clutch quits engaging for no apparent reason. Just take it to an AC shop and have them evac/rinse/refill the system and it will be good for say another decade or so.

The actuators... arrgh... depending on which parts bucket yours were pulled out of when the car was built the main gear in each actuator may be metal or plastic. The plastic ones crack over time and then the blend doors won't move. The actuators are a little fiddly to replace but do-able without taking the entire dash apart. I suspect you already found the writeup by now. Suggest you get the replacements off Amazon.com or rockauto.com. By the way -- a junkyard-bought actuator is a good bet, if you look in somewhat older GM cars you can find the actuators with the metal gears (junkyard will have access to the Hollander cross reference). The internals were more or less interchangeable and in my experience the older ones with metal gears did not break much. The ones with plastic gears will run for a while with a cracked main gear.

Please don't take this the wrong way BUT "the clutch looks OK" is tough for me to understand without seeing the clutch in operation. The Riv AC runs darn near all the time when the control head is in AUTO mode. Turn on the AC and look at the compressor, see if the clutch is slipping (you might hear a scraping metal sound when clutch is engaged, maybe faint, or a sound like a bell or cymbal when disengaged and engine running). Clutch is replaceable without evacuating the system if you are a contortionist.

SO...

- if the clutch is engaging either the system is under/overcharged or one or more actuators have failed.
- if the clutch is not engaging the first thing to check is, is there enough refrigerant in the system? You may prefer to have a shop do this because the "leak stop" and other junk additives that comes in the little cans isn't good for your system at all. They can check it for leaks with a sniffer, if you have not monkeyed with the system or wrenched the lines then there are not likely any leaks.
- if you do need an evac and refill be sure to replace the orifice valve with either the fixed or variable version. Variable is somewhat better.

Albertj

I recently recharged my AC (it was blowing only warm air) and discovered it works great... on the passenger side. And now that the clutch is engaging (it wouldn't when it had no charge), it does the ringing bell thing when it's disengaged. So it definitely needs the actuator and the clutch.

Good luck fixing one problem only to discover like eight more.

Thanks for all the helpful input and I will have hubby check further. Last he told me was that now the converter (?) wasn't working either.