07 S60 AC Help - Hot air/cycling compressor

[soulvoid21]

I just tried letting some pressure out before starting the car to be safe, then started it with the AC running and continued to let some out until the low side went under 40PSI. Now I'm getting basically no cooling on either side. Drivers is hot and passengers is pretty warm. High side pressure is way too low too.

Photos of current gauge readings at 73F and 30% humidity, and the R134 that I'm using.

Will recheck once I have my scan tool shortly.

[soulvoid21]

Got access to my scan tool finally, but unfortunately it doesn't read the pressure switches. I assume this would be under the CCM? Because I can read that entire module and others, but I didn't see anything about AC pressures or switches.

I can see evap and cabin air temps, both of which look to be reporting normal. When I first start the AC system, evap temp drops a little bit to 27C, but will climb up to 32C or even higher than cabin temp after a bit, which is exactly what it feels like coming out of the vent. Cold on passengers and then hot after a little bit with the above pictured pressures.. I won't add anything more to the system until we get somewhere with this info.

In the wave graph photo, from the start AC was turned on. Turned it off for the flat spot and then turned it back on. You see it drop a little bit in temp but then go right back up.

[yanga001]

I found the pressure data under live data in ECM on my scanner (Foxwell Scanner). Should be buried somewhere in there as even VOLFCR did it for my 1998 V70. Not sure where icarsoft keeps it.

Seems like how my system ran when undercharged. Is your compressor cycling when this data was captured (I am assuming it was).

Lets list all our data again:
You have no leaks
You have a new condenser and dryer on there
Evap is original
The heating effect of the HVAC is exactly what would happen to mine (08 S60) when it was low charge (my compressor was fine, had a bad leak at the condenser). I have seen an XC90 which had full charge but could not build up pressure due to a bad compressor, therefore it could not cool.

You have replaced the compressor, however you had 1-2 stints where the compressor locked up. Not saying their is damage but we cannot eliminate the compressor as a failure point now.

You have charged the system up to 40-45PSI low side but noted very low high-pressure measurements with your gauges.

The compressor has locked up due to overcharged

No codes means the pressure switches are not in the danger zone. I am surprised there was no stored code for the compressor lockup.
----------------------------------------------------------------------------------------------------------------------
What we have not eliminated:
partial blockage in the evaporator

The pressure data could help if you could find that.

[soulvoid21]

I will do my best to check every area of the scan tool after dinner, or even reach out to the manufacturer of the scanner if necessary.

[soulvoid21]

Checked the scan tool and it does show AC pressure, along with some other items. Video below showing activity with the same charge as previously stated.

[yanga001]

That is odd...

It is reporting close to 130psi (893 kpa) when the car is off which seems to be okay according to some online sources. I believe mine were in the 600-780 kpa range when off but i do not recall the exterior temperature it was at. I cannot check mine now as it is 5C out here in canada.

Link to charm.li on AC operation
https://charm.li/Volvo/2007/S60%202.5T% ... on/Design/

When compressor is on, your high pressure line drop off significantly and it seems that is when you are reporting the air "heating up" coming out. The high pressure is reportedly low which coincides with this observation. At around 24C it should be about 1000kpa according to R134A charts.

So what we have, if i read correctly is the following:
Low side pressure should be around 40psi which is correct for R134A at this temperature
High side pre-compressor activation is around 700-900kpa which appears to be normal for the given temperature.
High side post-compressor activation is <200kpa which appears to be extremely low, and is a problem.

So we have low pressure normal, high pressure low situation.

The car is making the call for the compressor to activate according to your code scanner, so that is good.
We know the CCM is not blocked by a code and is attempting to activate.
By feel you say that the sides are somewhat cold at the start and then heat up.
Your EVAP is not iced up as the temperature sensor (if correct) is leaps and bounds above freezing (in your previous post).
Your car also doesnt get cold enough to cause rapid ice up based on what we have read.

I am hesitant to say its a blockage as you get partial performance and have replaced multiple lines. It is possible so id recommend another test as linked at the bottom. I dont know if a feel test will work in our cars.

You are also able to get some cold which means it is partially functional, but not optimal. Therefore it cannot be a full system blockage. Your car holds charge so no leaks.

If i had to guess based on this then it seems to coincide with a poorly compressor.

I have done reading before where excessive oil buildups can "replace" the refrigerant and cause poor performance. I do not know if that is a factor here as you have changed out a fair number of parts already where oil would collect.

===================================================================
Additional data could be collected via this method maybe (feel test)
https://restomodair.com/blockages-in-a- ... m-circuit/

This link provides some stats but its for a low refrigerant situation
https://www.swedespeed.com/threads/air- ... re.196199/

[soulvoid21]

That is odd...

It is reporting close to 130psi (893 kpa) when the car is off which seems to be okay according to some online sources. I believe mine were in the 600-780 kpa range when off but i do not recall the exterior temperature it was at. I cannot check mine now as it is 5C out here in canada.

Link to charm.li on AC operation
https://charm.li/Volvo/2007/S60%202.5T% ... on/Design/

When compressor is on, your high pressure line drop off significantly and it seems that is when you are reporting the air "heating up" coming out. The high pressure is reportedly low which coincides with this observation. At around 24C it should be about 1000kpa according to R134A charts.

So what we have, if i read correctly is the following:
Low side pressure should be around 40psi which is correct for R134A at this temperature
High side pre-compressor activation is around 700-900kpa which appears to be normal for the given temperature.
High side post-compressor activation is <200kpa which appears to be extremely low, and is a problem.

So we have low pressure normal, high pressure low situation.

The car is making the call for the compressor to activate according to your code scanner, so that is good.
We know the CCM is not blocked by a code and is attempting to activate.
By feel you say that the sides are somewhat cold at the start and then heat up.
Your EVAP is not iced up as the temperature sensor (if correct) is leaps and bounds above freezing (in your previous post).
Your car also doesnt get cold enough to cause rapid ice up based on what we have read.

I am hesitant to say its a blockage as you get partial performance and have replaced multiple lines. It is possible so id recommend another test as linked at the bottom. I dont know if a feel test will work in our cars.

You are also able to get some cold which means it is partially functional, but not optimal. Therefore it cannot be a full system blockage. Your car holds charge so no leaks.

If i had to guess based on this then it seems to coincide with a poorly compressor.

I have done reading before where excessive oil buildups can "replace" the refrigerant and cause poor performance. I do not know if that is a factor here as you have changed out a fair number of parts already where oil would collect.

===================================================================
Additional data could be collected via this method maybe (feel test)
https://restomodair.com/blockages-in-a- ... m-circuit/

This link provides some stats but its for a low refrigerant situation
https://www.swedespeed.com/threads/air- ... re.196199/

I'm leaning towards a damaged compressor as well. Even the refrigerant lines in the engine bay, the low side would get ice cold and sweat like crazy with original system. But now, even the line going from compressor to evap doesn't get that cold. It's cool to the touch, but not as cold as I'd expect. And the hot side from evap to condenser doesn't get warm at all, same with the condenser itself. Barely any heat at all. I will do another feel test based on the info you linked above, very helpful ways to check for blockages.

The compressor also does not seize until the engine is put under load, but I've had it seize up about 5-6 times if I recall correctly. The compressor is noisy as I stated before. Nothing insane, but it's definitely louder than the factory unit. As I add R134 though, it definitely gets louder and louder too.

But our XC90's compressor is also somewhat noisy and I'd say makes similar sounds, that system is factory and works totally fine.

I'll test for blockages tonight, but seems like I should start planning for another compressor and have my mech add 1000g right out of the gate, instead of having me attempt to add more by feel.

[yanga001]

Here is my data for a 25c day.

One shows the ac off at 693kpa

One shows ac on at 1500rpm with 1033kpa


One shows evap temps sub 10c with 1500rpm and ac on. The first photo I took was when I just turned on the ac.

IMG_8379.jpeg (667.09 KiB) Viewed 395 times

IMG_8375.jpeg (456.43 KiB) Viewed 395 times

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IMG_8377.jpeg (646.94 KiB) Viewed 395 times

[soulvoid21]

Here is my data for a 25c day.

One shows the ac off at 693kpa

One shows ac on at 1500rpm with 1033kpa


One shows evap temps sub 10c with 1500rpm and ac on. The first photo I took was when I just turned on the ac.

IMG_8379.jpegIMG_8375.jpegIMG_8376.jpegIMG_8377.jpeg

I've already got the 3rd replacement compressor, and it's going back to my mech on May 15th. They're going to pull the old, inspect it for damage, check again for blockages and debris (specifically paying close attention at the evap being it's original), and then are going to straight add 1000g (2.2lb) of refrigerant per the dealer, instead of doing 1.54lbs (or 700g). If it still seizes again or still has weird pressures, we're going to replace the evap.

I did confirm they added 2oz of oil to the condenser when that was replaced, both times because they are not pre-oiled. Compressor comes pre-oiled so nothing should need added. No original oil was removed either, except for the oil in the original condenser obviously.

They were also adding refrigerant in US pounds, not grams. Granted, it shouldn't matter as long as you convert the numbers correctly, but they're going to put their AC machine into metric and do it in grams this go around.

[jonesg]

that icarsoft scanner looks very nice, the software is more logical then vida.