Mon Sep 13 2010

Pilot / pax heat control

So this evening, I decided to work on a modification to the heater plenum. My friend, Tom Webster has mentioned to me in the past that in order to get the passenger side hot enough to be comfortable, his feet were roasting. Apparently the heater opening is located such that most of the heat blasts out of the pilot side. You can see the cutout in the firewall, and the incoming air is actually directed at a 45 degree angle right at the pilot side louvres which makes the situation worse. So, he recommended that I add some method of shutting off the louvres on the pilot's side. BTW, it's probably obvious, but I haven't gotten around to bending these louvers outward yet. I'll do that sometime later.

So, I took the part down the basement and started cutting out cardboard templates of different concepts. Here's one with a pivot point down at the bottom. In the center position (as shown), both sides get as much air as possible.

...and here it is with the pilot's side closed off. Err...sort of. Ok, not really. This isn't gonna work.

Maybe if I move the pivot point to the right somewhat?

Maybe not.

Hrm...pivot point at the top? I'm not real keen on how it covers part of the passenger side.

...but it does a pretty good job of covering the pilot side when pivoted over.

This quarter circle covers the pilot's side well, but there's no where to pivot it to.

What if I made a collapsible fan shaped thing?

That kinda works, but I bet it'll be flimsy as heck and probably rattle around a lot.

Maybe a simple rectangular block. In the center, it covers about a third of both pilot and passenger side louvers.

...but does a good job of blocking the pilot side vents when slid sideways. Well, except for the one on the side (you can just barely see it at the right side of this photo.

Hrm...what if I cut angled slots that kinda match up with the louvers. This would be full blast open.

Sliding it to the left about a half inch closes it off...well probably 90% closed...except for the louver on the side. Hrm, this gives me an idea. If I designed it so that it was in the closed position when slid to the right, I could cover off the side louver as well. Let's give that a try.

I blackened the portions of the louvers which will be bent outward to make it easier to see this next attempt.

Here it is in the open position. Decent air flow through all louvers although the one on the side won't have as direct a path as before.

When I slide the contraption 1/2 inch, it covers probably about 90% of the three front louvers and all of the side louver. Schweet! This should be pretty easy to make, also. Took about two hours of noggin' scratchin' to come up with this, but I really like the solution. Next step will be fabrication!