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Old 02-28-2016, 11:46 AM   #1
Thundarr
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Heater Control

I've got a stock setup with AC and the temperature control never quite seems to completely shut off the heater valve. Similarly the AC system checks out, but never quite gets cold. It seems like the AC is fighting the heater.

I have already replaced the Heater valve and check to make sure it is getting vacuum to operate. My next step might be to change out the panel control to make sure it is passing on the full vacuum to the valve. I guess I could just put a manual ball-valve uder the hood to shut down the hot antifreeze to the heater core in the warmer months.
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Old 02-28-2016, 12:31 PM   #2
Wrenchbender Ret
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Re: Heater Control

There is a housing under the dash with a flapper in it. It is notorious for the flapper coming loose. That might be the problem or part of it.
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Old 02-28-2016, 12:33 PM   #3
Grumpy old man
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Re: Heater Control

^^
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Old 02-28-2016, 03:33 PM   #4
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Re: Heater Control

Thanks, I'll check the diagram.
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Old 02-28-2016, 04:47 PM   #5
LockDoc
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Re: Heater Control

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Also may have a mouse nest in it keeping the diverter door from working....

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Old 02-28-2016, 07:44 PM   #6
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Re: Heater Control

Got it fixed.

Let me explain for some other future poor soul, who messed something up while trying to fix something simple.

After changing out all the old air vent lines, I re-positioned the cable for floor/defrost diverter controls with too much bend. I straightened out the path so now the lever on the control slide panel had its full travel. Because it wasn't able get to its intended end, it kept the temperature control from fully extending so it wasn't fully closing the vacuum line to the heater control valve.

In essence, it wouldn't let the valve shut off the flow of hot water through the core. So in a way, it was a control issue.

Many thanks!
Thundar
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Old 03-03-2016, 12:15 AM   #7
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Re: Heater Control

Quote:
Originally Posted by LockDoc View Post
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Also may have a mouse nest in it keeping the diverter door from working....

LockDoc
OMG, you too? I just took a clump of floor insulation and kleenex out the other day. LOL

I have a broken lever, and other issues to work on, project #89.
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