Cabin Heat for an AeroVee - looking more promising

[mike.smith]

Mike,
Even with that setup I rarely have the firewall valve open all the way. Usually, the control cable is only out about 1 inch to heat my cabin

In my last test, closing down the firewall valve half way made the temperature DROP precipitously. So I was not able to create more heat by closing down that valve. Just the opposite. It's going to take a lot of flights with lots of different settings to see where the dust will settle. I also have a feeling based on my tests that to get the best heat for a given temperature would require changing the opening at the baffle. Colder OAT, smaller opening. Higher OAT, larger opening. So it may not be possible to "fire and forget" one baffle opening size for the winter.

[pappas]

That is really weird that we are getting such different results with the same set-up. One might say...baffling??

Maybe you should try opening the engine baffle pivot valve all the way and fab a way to temporarily close some of the muff outlet holes. (alum tape?). Restricting the muff outlet holes may keep air in the muff longer and possibly keep more heat. I bet it would be worth a call to Dave at Custom Welding. I am pretty sure he would be happy to help.

[pappas]

Mike,

I have the firewall and floor insulated and carpeted. Sonex B plastic trim panels on each side of the seat. No insulation on fuselage walls forward of the seat. I did sew up a baggage compartment and a divider which closes off the back of the cabin from the fuselage. The divider and sling did make a noticeable difference for me. Without insulation, you may never get the results I get. That would be too bad cuz heat is nice.

I agree, building a Sonex light is important for most of us. I never intended to put 2 people in this one so I packed mine with equipment, insulation, paint, 2-inch foam seats, 5-inch tires and lots of avionics. It is heavier than my last Waiex. I have to guess that makes a difference in this heat thing.

[mike.smith]

Mike,
I agree, building a Sonex light is important for most of us. I never intended to put 2 people in this one so I packed mine with equipment, insulation, paint, 2-inch foam seats, 5-inch tires and lots of avionics. It is heavier than my last Waiex.

That's the great thing about experimentals, right? Make it fit your personal mission! :-)

[OneTallShort]

Isn't the difference between your two setups that Lou has a turbo, and the other bird is normally aspirated? Anouther 20 hp of restricted pipe temperature could make all the difference in generated heat.

I have a turbo that I haven't started yet. My plan for heat was to use the exhaust pipe after the turbo, but I may be rethinking my plans. Especially with Lou's Lou's results...

[pappas]

I completely forgot that Mike is running normally aspirated. It seems reasonable to me that the 4 into 1 set-up could reduce the rate that the exhaust flows through the heat muff in our two applications. That would mean less heat transfer to the air directed to Mikes cabin than mine.

Restricting the flow exiting the muff could be the best bet. Probably a balance needs to be achieved that keeps the air in the muff for the longest possible time and still supplies enough flow, (perhaps reduced), to the cabin to make a difference. Maybe for Mike, that would take longer to heat the cabin than my set-up does but still may work.

[pappas]

Mike,
I have been thinking about your tests. If the measured temp at your heater outlet is 60 degrees with an OAT of 18 degrees, (a 42 degree difference), you are definitely getting 60 degrees into the cabin. But, as your cabin has so little, or no, insulation, the cabin itself can't keep the heat.

I would be interested to see what happens if you simply tape up a few pieces of old carpet to the firewall, (as much of it as you can cover anyway), the floor and side walls forward of the spar tunnel and place a piece of cardboard or tape a piece of old carpet behind the seat to block off the aft fuselage. That might be a pretty good source of data. Also, weigh all of the pieces. Who knows!