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The A/C is barely cooling and I'm racking my brain trying to figure out the next step to figuring out the issue.
The temp delta was 15 degrees F from ambient(90 degrees F) low side was 56psi and high side was 135 psi. I added about 1.5 pounds of refrigerant and the delta only increased to 20 degrees, low side was 64psi and high was 220psi. The fans increase in speed as the high side pressures increase which tells me the high side pressure/temp sensor is working and there's liquid at the high side port. It's acting like it's still undercharged or the expansion valve is partially stuck open flooding the evap...which would kind of make sense given the low side pressures are elevated and the temp delta sucks.
Are these systems designed to run at really high head pressures or are there and known issues that present with similar symptoms?
I didn't take the line temp exiting the evap but its cool but not cold enough to sweat if that's helpful.
second picture is a chart I Found online… first picture of my gauges at 95 F outside .. I added about 12 Oz and my low Pressure came up to 45lbs and High pressure was 190…the air temp at the vents was 49F
My 2011 GL550 will freeze you .
I would think you have a blockage in the system
Last edited by vesiadog; Yesterday at 06:36 PM.
Reason: picture
WIS states to completely evacuate the system and fill with a specified amount of oil, and a very specific mass of refrigerant.
in my experience 9/10 ac systems leak out refrigerant over time so adding small amounts in several increments until desired temps and delta p is achieved also works, if you don’t want to or are unable to follow WIS method.
Why it leaked in the first place and where that leak is should be evident if you add some dye to it.
second picture is a chart I Found online… first picture of my gauges at 95 F outside .. I added about 12 Oz and my low Pressure came up to 45lbs and High pressure was 190…the air temp at the vents was 49F
My 2011 GL550 will freeze you .
I would think you have a blockage in the system
Thank you for the reference, do you remember the rpm level the pressures were checked at? Are you referring to an air or refrigerant blockage? I'm thinking txv could be stuck open flooding the evaporator. The low side would read high since there's very little cooling occurring
WIS states to completely evacuate the system and fill with a specified amount of oil, and a very specific mass of refrigerant.
in my experience 9/10 ac systems leak out refrigerant over time so adding small amounts in several increments until desired temps and delta p is achieved also works, if you don’t want to or are unable to follow WIS method.
Why it leaked in the first place and where that leak is should be evident if you add some dye to it.
I'll follow the WIS method and use a leak detector once the no cooling issue is nailed down. It's just really odd that there was so little change in temp over a broad range of pressures.
Yesterday, 12:30 PM
