Heater control valve for '72
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,818
Likes: 470
From: Wichita Kansas
Heater control valve for '72
I won't presume instructions will come with the purchase of this part, and I was not able to find it in the AIM and the '72 Service Manual so I must ask. Where is the vacuum source for this part and what exactly makes it work? I want to replace the gate valve that I hurriedly installed years ago with the correct application. Thanks 
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,818
Likes: 470
From: Wichita Kansas
Unbelievable
I won't presume instructions will come with the purchase of this part, and I was not able to find it in the AIM and the '72 Service Manual so I must ask. Where is the vacuum source for this part and what exactly makes it work? I want to replace the gate valve that I hurriedly installed years ago with the correct application. Thanks
Team Owner
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From: Southbound
Cruise-In II Veteran
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
For vehicles WITH that valve, the vacuum signal to it comes from the little distribution manifold mounted on the left side of the heater control in the lower console. One of those manifold outlets is fed out thru the firewall to control that water shut-off valve.
I'm pretty sure that the A/C vehicles had them, but don't know about the others.
I'm pretty sure that the A/C vehicles had them, but don't know about the others.
Drifting
Joined: Aug 2006
Posts: 1,729
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From: Scottsdale Arizona
I have a 72 and on the passenger fender well there are two dimples where the shut off valve was mounted previous years. I purchased one and the found out 72 did not use one I guess you could still mount and use it.
Advanced
Joined: Jun 2013
Posts: 56
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From: Ontario, Canada
This is interesting that in 71 there was a wh-strip vac-hose per Alan that was used for this valve. But in 72 the vac-hose and valve were removed and do not exist. The design was changed and GM removed it. I'm wondering if it was not effective so GM just removed it all together????
Derrick
Derrick
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Safety Car
Joined: Apr 2006
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From: BC
I think this is for AC cars only as it would require a shutoff. My 69 BB is non AC and doesn't have one. It sounds like a really good idea for summer but I don't think there is a place to hook it up on the non AC console heater/vent control.
Advanced
Joined: Jun 2013
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From: Ontario, Canada
I've not driven my 72-Air car in the summer so I cannot comment on the heat inside. I've only read about how hot these cars are here on this forum.
So is it a MUST to put a manual shutoff valve in the heater core line or do you just go with how GM designed it without one?
thanks Derrick
So is it a MUST to put a manual shutoff valve in the heater core line or do you just go with how GM designed it without one?
thanks Derrick
Team Owner
Joined: Jan 2006
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From: Crossville TN
If your car doesn't have a shut-off valve, then you SHOULD add one to cut off hot water flow to the heat exchanger [heater] in times of warm weather. A simple brass in-line ball valve (90* turn lever) will get the job done. You can insert it into either heater hose line running along the right inside fender housing. Putting it near one of the hose hold-down clamps would keep it from moving around. Paint it 'satin' black and no one will even notice it.