AC Compressor or low freon

[dragono]

Hey all, in a bit of a pickle. Went to start my ac on a warm day and she’s just blowing cold.

Now I consider myself a pretty good backyard mechanic as this is the second one I’ve rebuild from previously wrecked. In any case, depressed both the high and low side and verified there is r1234 still in the system. However no idea of how much, I also ran a system test that showed the evap temp only dropping to 60 ish degrees on that warm 80 degree day. I’m hoping my compressor didn’t die over the winter randomly and that I’m just the owner of a slow slow leak. I’ve also hooked up the ac tools and managed to get 130psi on the high side and 20 on the low side with system on full blast. Just thought I’d throw this up on here before I throw parts at this thing before summer hits. The damage was to the front and the condenser was replaced after the accident with no other components being removed from the ac system. Also it was vacuumed down and maintained vacuum before being charged. Last summer once it was charge it worked great btw.

Send help lol.

 

[oddball]

Most likely a leak. I'm not familiar enough with r1234 yet, but 130/20 sounds pretty low.
First step will be finding the leak. You can do that yourself or hire it out. Might need to inject some dye then use a UV flashlight. It'll be a very, very slow leak, most likely from one of the connections that came apart to replace the condenser.

Well, the other possibility is the compressor. It's a fancy variable displacement unit, controlled by a solenoid. The wiring might be messed up or something going wrong with the compressor and it's not getting beyond minimal displacement.

One way to check this out is to evacuate the system with a real machine that weighs how much comes out. Then you'll know if it was a leak or a compressor problem.
r1234 is still a PITA for the DIYer.

 

[dragono]

General update in case anyone ever reads this post, I rigged up the most Janky evacuation machine i could. Pulled the compressor out of a dehumidifier i hadn't used in years. Purchased a refrigerant tank off amazon, this was the most expensive piece ($80), and got some fittings from lowes to plub it all together.

Plumbing it all up was a nightmare because who knows 1/4 MIP from 1/4 FIP from 1/4 Flare from 1/4 compression so there was a learning curve. But long story short once i got it all connected i managed to get a whole 2 ounces out of the system. Tank weight was 16lbs 8 oz and completion it was 16lbs 10oz. After i was done i depressed the low side connection on the car and felt vacuum so i know shes empty.

Being that the car was in a front end collision im going to guess the seals connecting the condenser inlet and outlet are janky. I almost wish the leak were worse so it'd be easier to find but this one is going to be a bit of a bear to find so i'll just replace o rings and if it still leaks after that i'd say there's a hole in the condenser that smaller than the tip of a needle.

 

[dragono]

Follow on update, My shradder valve on my low side line was leaking. I should say i lost the dust cap when i first rebuilt and though to myself. Whatevs, so word to the wise keep the valve covered.

I will say adding refrigerant to this "smart" system is harder than older cars. I'll caveat this by saying its 45 degrees out so my garage was only at a balmy 60 are so. After vacuuming down the lines again i added refrigerant and set the system to cold and max air as youd do in an older car.

However, it was taking a mighty long time to add refrigerant. I suspect this is because, although the compressor is "on" is a variable swash plate type and the system is either reading something along the lines of . Its already cold enough so no need to compress any more and ofcourse if the compressor isnt compressing real hard its harder to pull in fluid from the low side. To bypass this is my case i just had my AUTEL run a compressor test that forces compressor on and full swash plate engagement. Pull the fluid right in after that.

If i didnt have the fancy scan tool, i suspect the only way to trick the system into doing it under such ambient conditions would be to heat up the engine bay and turn off re circulation mode so it pulls in warm engine bay air.

Or just wait till its a hot day and it should mimic a normal clutch type compressor. In any case the dust cap part number for the low side is so i plan on ordering the part since its all of $10.

Part number is: 97811H9150​

 

[Clearly Canadian]

Same issue (warm air coming out of AC) on my 2018. They did some initial troubleshooting ie replaced seals and topped up refrigerant. That bill was ~$500 (Canadian) and covered by extended warranty. I paid a $100 deductible only. But it didn't solve the problem.

So they ordered and installed a new compressor with an eye watering repair cost of $1100 labour and $1200 for the part. Like whatttt.

 

[Clearly Canadian]

By the way my mileage is 60,000 km so it's still a baby.

 

[djerickd]

Follow on update, My shradder valve on my low side line was leaking. I should say i lost the dust cap when i first rebuilt and though to myself. Whatevs, so word to the wise keep the valve covered.

I will say adding refrigerant to this "smart" system is harder than older cars. I'll caveat this by saying its 45 degrees out so my garage was only at a balmy 60 are so. After vacuuming down the lines again i added refrigerant and set the system to cold and max air as youd do in an older car.

However, it was taking a mighty long time to add refrigerant. I suspect this is because, although the compressor is "on" is a variable swash plate type and the system is either reading something along the lines of . Its already cold enough so no need to compress any more and ofcourse if the compressor isnt compressing real hard its harder to pull in fluid from the low side. To bypass this is my case i just had my AUTEL run a compressor test that forces compressor on and full swash plate engagement. Pull the fluid right in after that.

If i didnt have the fancy scan tool, i suspect the only way to trick the system into doing it under such ambient conditions would be to heat up the engine bay and turn off re circulation mode so it pulls in warm engine bay air.

Or just wait till its a hot day and it should mimic a normal clutch type compressor. In any case the dust cap part number for the low side is so i plan on ordering the part since its all of $10.

Part number is: 97811H9150​

Was this fix still holding good? Did you replace the valve as well?

Mine is blowing HOT now. so starting the troubleshooting process..