AC pipes icing up
Thread Starter
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
AC pipes icing up
I read some other posts about this issue on what seems to be this cause/remedy.
Seems like after about an hour of running at cruise the AC system operation goes down to about a 10% efficiency that is hardly no vent output, a faint gurgling sound and barely cool at lowest temp setting. When I stop and inspect, the larger pipe across the firewall with large brass fitting (I need to look up the proper names) and the smaller line with the ports on it are solid ice. Once the ice melts or if I turn off the AC while driving for about 15 minutes and cycle it back on it starts to work ok again. For normal short runs, the AC gives no indication of a problem and will freeze the occupants set at 77°F. Albeit I live in a very humid environment, seems like I'm see more frequent fogging of the windshield over the defrost vent with the AC on.
I've also noticed there is a difference in the general tables for the specific ambient temperature provided on the refill instructions vs. the tables in the FSMs.
What do you all suppose is the issue here?
Seems like after about an hour of running at cruise the AC system operation goes down to about a 10% efficiency that is hardly no vent output, a faint gurgling sound and barely cool at lowest temp setting. When I stop and inspect, the larger pipe across the firewall with large brass fitting (I need to look up the proper names) and the smaller line with the ports on it are solid ice. Once the ice melts or if I turn off the AC while driving for about 15 minutes and cycle it back on it starts to work ok again. For normal short runs, the AC gives no indication of a problem and will freeze the occupants set at 77°F. Albeit I live in a very humid environment, seems like I'm see more frequent fogging of the windshield over the defrost vent with the AC on.
I've also noticed there is a difference in the general tables for the specific ambient temperature provided on the refill instructions vs. the tables in the FSMs.
What do you all suppose is the issue here?
Thread Starter
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
The table on the refill bottle says for example a 90°F ambient temperature, the low side should read 45-55 psi, for a 86-95°F ambient temperature the FSM says for above 50% humidity low port pressure should be 30-35 psi. That's quite a bit of difference if you ask me, wonder which is correct?
Yeah I need to take it to an AC service place...I'm one that likes to have an idea what the problem is before taking it in. LOL
Yeah I need to take it to an AC service place...I'm one that likes to have an idea what the problem is before taking it in. LOL
Thread Starter
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
Yeah not having much luck with AC systems, the house AC is doing the same thing as of late last night. Froze up solid no air coming out vents and pipes froze. AC guy this morning said low on freon so they have to wait for it to melt then they can service it. So wow even after several hours it's still froze. You'd think in this heat and humidity it wouldn't last! So both my system are low on freon. They said my cars' AC is probably low too I asked them just for grins.
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