Air Conditioning Issue - What could it be?

Hey everyone...new Outback owner here. Just bought a 1997 Outback which has an air conditioning issue and was browsing the web to see what the possible problems could be and stumbled across this site. Given I wrote as a condition of sale the dealer would repair the A/C this question is more informative and to say hi to the group. Returning to the Outback family after a three year hiatus when I traded my previous 1997 for a BMW X5. Love the Outbacks and happy to have rejoined the family again.

 

Situation: 1997 Legacy Outback with 166K miles, 2.5L engine, auto transmission. A/C does not blow cold air. System has adequate refrigerant, at least it was topped off while I was closing the deal, and the A/C compressor clutch does engage when the A/C button is pressed. However the air does not cool as expected. Movement of the temperature lever does change the air temperature from cool to hot so I assume the heater and blend doors are working. No unusual noises or sounds come when the A/C compressor engages. Everything appears to be normal.

 

I have some vehicle repair experience and know the basics of them so I'm wondering what might cause the problem. Since the dealer has stated they will repair the air conditioning I won't be doing the work myself. However I am curious and I want to ensure I understand what the potential causes are as I don't want them to try an pull the wool over my eyes. I will post the fix to this forum (I hate going to a forum, finding the exact problem I'm experiencing, and no solution is provided) but in the mean time...any thoughts?

 

Some additional information:

 

The vehicle appears to have had the drivers side head gasket replaced (seems to be common on these older Subaru's) along with the belts and a number of other items. Dealer also provided me a 30 day / 1,000 mile power train (engine and transmission) warranty...I'll be taking it to my mechanic for an inspection within the next couple of days as I think the idle is a little rough (my father, who owns a 2001 Forester, doesn't see it as a problem).

 

Thanks all!

I think the 97 has a receiver dryer on the left side of the radiator (about the size of a RedBull can). If the system is working you should be able to see some flow in the sight glass on top. That will verify flow. You should not see any bubbles in the freon. If you see bubbles the charge is low.

Doesn't apply to you in this instance, but if you have to repair your A/C check your local community college. When the A/C went out in one of my cars I took the A/C course and repaired mine in class for half the quoted prices.

Follow up: Had the air condition repaired today. It appears there was a problem with inadequate refrigerant in the system. I wasn't there to observe the repair however my friend stated the air conditioning guy did something with the low and high pressure valves and then added some addition refrigerant. It sounded a lot like what the mechanic (he is not an air conditioning specialist) did on Saturday.

 

In the end it appeared to be nothing more than inadequate refrigerant because the air is much cooler and inline with what I would expect from air conditioned air. The weather temperature is a lot cooler today than it was on Saturday so it's difficult to say how effective it is at cooling but it's an improvement over what it was.

 

Thanks for the feedback David E. Looks like you were on the right track.

If there wasn't enough Freon in the system the compressor wouldn't even kick in. On my 96 L everything seemed to work, the compressor would kick in but when I would touch the high and low pressure lines they both were hot. The compressor ended up being the problem, the shaft inside broke and wasn't pumping Freon.

If there wasn't enough Freon in the system the compressor wouldn't even kick in.

This was my thought as well. However I observed the mechanic, the one who charged the A/C system the day I purchased the car, fill the system with refrigerant and then the compressor began to engage (where it had not before). I can't explain it however I surmise the system wasn't adequately charged to cool but sufficiently charged to allow the compressor to engage. One thing I do know is the system is cooling a lot better after the A/C guy worked on it yesterday compared to how it performed after the mechanic worked on it Saturday.

 

With that said the weather temperature was cooler yesterday than on Saturday when I bought the car. So there is the possibility it could just be cooler due to the cooler weather. But it does exhibit the cooling behavior I would expect from a properly working A/C system. However I did tell the dealer I'm not signing off on it until it warms up again (it's snowing and in the 30's today whereas it was in the mid 70's on Saturday) and I can confirm.

If you have to take it back in make sure they completely evacuate the system, verify it holds vacuum, then put the freon back in. If there is air in the system from being opened for some reason you can add freon to get the compressor to kick in and will get some degree of cooling, but not as much as it was designed for.

If you have to take it back in make sure they completely evacuate the system, verify it holds vacuum, then put the freon back in. If there is air in the system from being opened for some reason you can add freon to get the compressor to kick in and will get some degree of cooling, but not as much as it was designed for.

This sounds like what may have happened on Saturday. I believe the system was recently opened as it looks like there was some work on the engine. The drivers side head gasket looks as if it was replaced. Would this require opening the A/C system? Might be a good idea for me to take it to a qualified shop to have the system evacuated and the recharged.

In your first post I thought you mentioned the compressor did kick in.

In your first post I thought you mentioned the compressor did kick in.

That is correct. Which is why I was surprised when the fix was to add more refrigerant. From what was described of the "repair" it sounded a lot like bleeding the system. It appears there is the possibility the system could have sufficient refrigerant to allow the compressor to engage but insufficient to provide adequate cooling.

 

One additional point to mention: I did not observe the compressor cycling after the initial compressor clutch engagement. With the A/C switch off the compressor clutch was disengaged. When I put the A/C switch in the on position the compressor clutch immediately engaged. However no cooling was observed nor did I observe the compressor cycle. It's my understanding once the system has begun to cool the compressor will cycle off to keep the system from freezing. In normal operation it cycles on and off in order to maintain the temperature.

 

Unfortunately we've had another round of cold weather so I haven't had an opportunity to test the system on a warm(er) day. I did have my friend inform the dealer I do not consider this repaired until I've had an opportunity to test it on a warm day.