Use of the heater

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tlake
Posts: 476
Joined: Wed Feb 03, 2010 6:33 pm
Location: WA

Use of the heater

Post by tlake »

According to the 1976 owner's handbook you are supposed to use the fresh air fan when the heater is in use. I assume this is so air can blow over the heater core and stop it getting too hot.

As I said before, the heater on my 1976 e12 with factory a/c, still works when the a/c is on, if I want it to. However, while it is still running with the a/c on, the fresh air fan has cut out, but the a/c fan (console blower) is running. Note that early a/c cars had separate controls for the a/c.

So, is it ok to run the heater and a/c simultaneously given the a/c fan (console blower) is still running and blowing cold air behind the dashboard :?: I know this sounds like one of those letters people used to write to Smokey Yunick in Popular Science car tech section (Say Smokey?), but what do you think :?: :lol:

The reason I would want to run both heater and a/c together, is that in winter I like to use the a/c to stop the seals drying out, and that's more pleasant to do in cold weather with the heater on.
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Mike W.
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Re: Use of the heater

Post by Mike W. »

At worst I'd run it with the vent open as I've done often over the years with the blower motor itself off, without any thought of A/C. On the subject of it, I wouldn't worry about not using it for a while, the swashplate compressors are pretty robust and IMO the weak link of the A/C is more the condenser getting hit by a rock and springing a leak.
Mike W.



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tlake
Posts: 476
Joined: Wed Feb 03, 2010 6:33 pm
Location: WA

Re: Use of the heater

Post by tlake »

Mike W. wrote: Mon Jun 20, 2022 8:28 pm At worst I'd run it with the vent open as I've done often over the years with the blower motor itself off, without any thought of A/C. On the subject of it, I wouldn't worry about not using it for a while, the swashplate compressors are pretty robust and IMO the weak link of the A/C is more the condenser getting hit by a rock and springing a leak.
I do the same, I use the heater with the vents open, and even when the fan motor is off you still get the hot air flow from the footwell vents with the car in motion.

I wasn't so much worried about the a/c hardware as the seals drying out. I have known people that during winter didn't use their a/c only to find they needed a regas because the seals dried out. In mild climates people running around in winter with the climate control shut off completely, and a window down.

The last time I recharged was back in 2007, so it has held gas probably from regular use. I have noticed that in some car handbooks it says to run the a/c about 10 minutes a month to stop seals drying out.
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