My friend Tom had once mentioned to me that the heat coming out of the heater louvers on his RV-7A wasn't evenly distributed between the pilot and passenger. Once when he took a trip with a passenger, in order to keep the passenger's feet warm enough, his feet were roasting.
Since I'm highly motivated to make our -7A as comfortable as possible for the wife (increased comfort level = more likely to fly) and since I know her feet are always cold, I thought this is a problem I should address. Thus, I decided to make a modification to allow directional control of the heat coming out of the heater manifold.
After thinking through several iterations, I decided on a sliding plate which would cover (or open) the louvers on the pilot's side. Here's what I came up with:
The open position:
The closed position:
Although the closed position doesn't block the front louvers completely, I'd estimate they're about 80% blocked and the one on the side is completely blocked.
The slider didn't operate smoothly at first, so I sprayed it down with LPS-2 and now it works pretty well. I'm sure this could be improved to make the motion smoother, but it should work well enough.
Also note the bellcrank mechanism. That added quite a bit of complexity, but I decided to go with it for two reasons:
It's a little hard to see how it works in the pictures, so here's a little video of the setup in action.
Take care,
Since I'm highly motivated to make our -7A as comfortable as possible for the wife (increased comfort level = more likely to fly) and since I know her feet are always cold, I thought this is a problem I should address. Thus, I decided to make a modification to allow directional control of the heat coming out of the heater manifold.
After thinking through several iterations, I decided on a sliding plate which would cover (or open) the louvers on the pilot's side. Here's what I came up with:
The open position:
The closed position:
Although the closed position doesn't block the front louvers completely, I'd estimate they're about 80% blocked and the one on the side is completely blocked.
The slider didn't operate smoothly at first, so I sprayed it down with LPS-2 and now it works pretty well. I'm sure this could be improved to make the motion smoother, but it should work well enough.
Also note the bellcrank mechanism. That added quite a bit of complexity, but I decided to go with it for two reasons:
- I wanted the default position (with the control knob pushed in) to be open. But since the control knob will be entering this heater manifold from the right side, I needed to reverse the operation of the slide baffle so when you push the control knob in, it pulls the slider.
- Also, I wanted the knob travel of this slider to be pretty much the same as the travel of the heater box. Since the heater box travel is about 1 3/16", and this slider only needs to travel about 1/2 inch, I needed the bellcrank to change (increase) the stroke.
It's a little hard to see how it works in the pictures, so here's a little video of the setup in action.
Take care,
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