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mrein3 · 10-02-2006, 08:29 PM

LOTS of people take the vacuum controlled valve out and put an in-line, manual one in. That works the best but on a day like today here in MN I had my heat on going to work and the air on going home. The vacuum controlled one is better for that.
Do you have the factory vacuum pod that bolts to the ac box on the outside of the firewall? Is it broken? I had a car once that had a leak in that pod. It behaved like you describe. Colder with more vacuum. Almost hot without.

A POA system always has the compressor engaged with the AC on.

I think if you solve the vacuum issues you'll get cold air from all vents.

Did you get your fan speeds all squared away?

10-02-2006, 08:29 PM	#2
mrein3 Registered User Join Date: Feb 2000 Location: Center City, MN, USA Posts: 3,254	Re: 72 A/c Air Conditioning Troubleshooting LOTS of people take the vacuum controlled valve out and put an in-line, manual one in. That works the best but on a day like today here in MN I had my heat on going to work and the air on going home. The vacuum controlled one is better for that. Do you have the factory vacuum pod that bolts to the ac box on the outside of the firewall? Is it broken? I had a car once that had a leak in that pod. It behaved like you describe. Colder with more vacuum. Almost hot without. A POA system always has the compressor engaged with the AC on. I think if you solve the vacuum issues you'll get cold air from all vents. Did you get your fan speeds all squared away? __________________ '70 cab, '71 chassis, 383, TH350, NP205. '71 Malibu convertible '72 Malibu hard top Center City, MN