AC not leaking, compressor running, but no cold air
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Joined: Mar 2005
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From: America
1999 C43 AMG, 2005 E55 Wagon
AC not leaking, compressor running, but no cold air
99 C43. AC isn't leaking. It's holding 95 PSI when off, and when engine on and AC on "LO" it reads 45psi on the low side and 290psi on the high side. If anything, the system has too much freon in it. Ambient temp is 80F.
AC unit indicates 14bar, so it's seeing pressure too. But I can't get cold air. AC unit reports evap temp is 94F (which is accurate, judging by how warm the air is coming out of the vents).
My theory currently is that the expansion valve has clogged. I know when the system is working normally you should see the high side pressure build, then drop, then build again, then drop, and repeat over and over; this is how the system causes the evaporator to become cold. But mine builds up to high pressure and just stays there.
Am I correct in presuming it's the expansion valve? Another weird issue: my aux fans never run. Sometimes I see them start to turn but they barely turn for a few seconds and never spin up to full speed. Car will get pretty hot (100C) in traffic if it's warm out and I'm in traffic.
And the million dollar question: is the expansion valve ALWAYS a complete dash-out procedure like it was on my 1994 C280?
And if someone has a better idea as to what the problem is, i would LOVE to hear it.
AC unit indicates 14bar, so it's seeing pressure too. But I can't get cold air. AC unit reports evap temp is 94F (which is accurate, judging by how warm the air is coming out of the vents).
My theory currently is that the expansion valve has clogged. I know when the system is working normally you should see the high side pressure build, then drop, then build again, then drop, and repeat over and over; this is how the system causes the evaporator to become cold. But mine builds up to high pressure and just stays there.
Am I correct in presuming it's the expansion valve? Another weird issue: my aux fans never run. Sometimes I see them start to turn but they barely turn for a few seconds and never spin up to full speed. Car will get pretty hot (100C) in traffic if it's warm out and I'm in traffic.
And the million dollar question: is the expansion valve ALWAYS a complete dash-out procedure like it was on my 1994 C280?
And if someone has a better idea as to what the problem is, i would LOVE to hear it.
