Al, Do you know what the 7 X 7 heater core came out of??

Bill B 

Hey Mark;

We've been looking at the same things with our install.  We talked to our exhaust guy, and he feels that with the exhaust temps that these rotaries have, that it might not be a good idea, (the muff).  Next step was hot water, plumbing, and a heater core inside some where, which was sort of a negative idea.  We kept all of our cooling lines exterior, so that a coolant leak wouldn't happen inside at about 10K feet, and 200+ knots, not a good scenario.  J.C. Whitney has a small electric heater that has some possibilities, so we are looking into that and some other ideas.

Greg Ward

Greg;

Having studied that option in the past; I’d suggest you save your time – unless you want to add another alternator.  For effective heating you’re going to need more than 1000 watts.  For a 14 volt system that’s over 70+ amps.

I don’t consider it a risk to run some relatively small diameter, high quality, heater hose (5/8”) into the cabin to a small heater core.  I have a 7” x 7” heater core, and it puts out at least 1500 watts, or more. See Mcmaster-Carr silicone hose, part #5296K12.  Pressure test your system each annual to about 35 psi.

Al G