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Heater always on


Sep 5, 2001
Clovis, CA
1971 Onterio Orange BB Covert
My '71 with factory A/C blows hot air from the vents unless the a/c is on. I have checked the blend door operation and adjusted the cable (door seems to work just fine), checked vac. at water control valve and it is normal, replaced water control valve, verified that all doors are operating properly. Anyone have ome ideas?:confused


I completely disconnected the heater hoses and removed them all together. This of course means you will never have heat but I dont need it where I live. I have heard of others putting a shut off valve in the heater hose so no water flows to the heater core. When winter rolls around just manually turn the valve to let the water flow again.
I did the same thing if you don't use it get rid of it,,But the fan still circulates the air. I remember reading in a thread that you can cut a wire in the harness and the fan will no longer run all the time but it will turn on when you run the air or the fan......Hmmm now where did I see that???
I've got a 77 that I've had for two weeks that does the same thing. Trust me, it's not fun in August in Atlanta and unfortunately I found out the hard way. It started to rain and I had to put the T-tops back on. Talk about an oven.

Until I can figure out how to fix it right, I plan to follow the instructions in Eric's link this weekend and see if I can get the temp in the car lowered for the last hot weeks of the year.

Cc, my fan doesnt run unless I turn it on. Possibly the last owner fixed that, or maybe it depends on the year of the car.
I can tell you that installing a heater shut-off valve really makes a difference. My interior temp is down well over 20 degrees during the summer. I don't really drive it in the winter, but I have the options to easily open the valve and have heat. For this reason, no need to remove the heating system.

Also, my fan runs all the time. There is a wire to cut to shut the fan off until the switch is placed in the medium or high position. I have the directions but need to find them.




To turn blower off instead of lowest speed:
Locate under hood, on pass. side at blower resister box, the wire at bottom of 4 wire T nearest pass side, dk. brown on 77. One can disconnect & bend that one connecter down & reconnect. This is fast & reverseable. Of course you could remove wire from connecter, esp. if you will be doing this often.
I started doing this years ago to save wear on blower motor, less noise w/ blower off & key on.
Don't need low anyway!

It seems everyone agrees on the addition of a shut off valve. Thanks
My father even had to fix his '82. He used a manual shutoff valve in the heater feed hose. Seems like an odd thing to engineer into a car sold almost anyplace in the US.

Steve :w

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