AC/heater control mod

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Jan 2, 2013 | 08:36 AM

trekbasso

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Fleet Mechanic

Joined: Dec 2010

Posts: 1,546

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From: Wellington, Co

AC/heater control mod

Okay, so a weird time of year to do this, but was simple and cheap. I spliced into the red vacuum line, and I don't have heat except heater position on down. I expected the left side of dial to be cool, but thought the heater/vent position would still be warm.?? Did I splice the wrong vacuum line? If I read correctly, the white line will do only the max ac position, and I was hoping for cooler vent and regular ac also.

Thanks.

Jan 2, 2013 | 09:04 AM

Supercab

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Joined: Feb 2000

Posts: 5,373

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From: Palm Bay, Florida

I did the RED line on mine a few years back and everything on the LEFT side of the OFF position is COLD, and non-adjustible.

On the RIGHT side of OFF everything is WARM ans IS adjustible.

-Hope I've helped you...

Jan 3, 2013 | 08:28 AM

trekbasso

Thread Starter

Fleet Mechanic

Joined: Dec 2010

Posts: 1,546

Likes: 9

From: Wellington, Co

Thanks Supercab. I am thinking of adding a vacuum switch, put it back to stock when I want more control. Otherwise I guess it is okay.

Jan 3, 2013 | 08:39 AM

mueckster

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Joined: Jun 2003

Posts: 8,298

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From: Damon (South East Texas)

Quote:

Originally Posted by trekbasso

Thanks Supercab. I am thinking of adding a vacuum switch, put it back to stock when I want more control. Otherwise I guess it is okay.

I have an electrically operated vacuum switch that I was going to use for that same purpose. I ended up scrapping that idea. If you make the gtg this weekend I can bring it, if you're interested. It could be tied into the a/c compressor control of the switch and use a full time vacuum source. That way it only closes the heater valve when the a/c is on.

Jan 3, 2013 | 08:43 AM

trekbasso

Thread Starter

Fleet Mechanic

Joined: Dec 2010

Posts: 1,546

Likes: 9

From: Wellington, Co

Not a bad idea, to at least look at it. I was thinking of a simple off/on, put the vacuum source back to stock when I want different control.
Thanks Roland.

Jan 3, 2013 | 02:20 PM

jeffreyt

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Joined: Jun 2010

Posts: 2,555

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From: Longview, TX

I still haven't quite understood the need for this mod/fix. Every one of these trucks I've been in has colder air than any other (minus a Mazda protege I had in highschool that blew ice out the vent). Have I just had good luck, or am I missing something?

I understand how the lines are ran and how the door blends and all, but I can rarely run the temp **** all the way left as it is. Maybe I'm just acclimated to the heat lol

Jan 3, 2013 | 03:19 PM

trekbasso

Thread Starter

Fleet Mechanic

Joined: Dec 2010

Posts: 1,546

Likes: 9

From: Wellington, Co

Basically it is up to personal preference. All other vehicles I have seen have some sort of heater control valve in the engine comp, cutting off the flow of coolant. I like running vent a lot, and before the air felt warm when it was 65-70 outside. This is because the air is picking heat up from the heater core, because hot coolant is always in the core. Cut off the heat, core cools off, cooler vent temp., and that means colder ac also.