Cabin heater coolant diagram

[Birdseyeview]

Larry, in reference to your diagram in Post #9. Is this the way Kitfox recommends you plumb the coolant lines? (i.e. in parallel to the main coolant radiator).


==
Michael

The Rotax diagram that I modified (in post #9) reflects the way my build manual instruction say to plumb the cabin heater. I've never seen a diagram published by Kitfox that shows the cabin heat exchanger included.

[avidflyer]

I have the heater installed on my new Kitfox 4 build, and here is what I did. As the heater core has 1" fittings, I ran through the firewall, through the heater core, back out through the firewall and then to the radiator. I am using a thermobob, but rigged up something that doesn't allow the thermostat to close completely, so I'm not using the bypass line. JImChuk

[avidflyer]

A bit further along. JImChuk

[bbs428]

Do you already have a heat exchanger? What engine? Hard to give you a diagram without knowing your system.

Kitfox has the whole setup for sale, or you can go really experimental and get an auto heater core, a shut-off valve, hoses and a fan for a lot cheaper and fabricate away! My setup was under $150.00. A bit more if you go with a more powerful fan. Pc fans don't move a lot of air tbh.
All the hose connections are on the other side of the firewall. No wet feet! lol.

I'll see if I have a pic of it all complete. Do a search and you might find something better to go with!

Good luck.

Attachment 31529 Attachment 31530 Attachment 31533

Just an update on the effectiveness of my heater setup.
I flew in 35 deg. cool morning autumn air and was pleasantly surprised that it really did a nice job. I have a valve on the engine side of the firewall connected to a choke-style on-off knob. The 4 high-speed computer fans do a nice job without too much noise or amp. draw. The electrical switch is just on-off with all four at full power when on. You can vary the amount of coolant flow to vary the heat output. I thought about some kind of air diverter, but the center console does a nice job dispersing the heat in the cabin.

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[patrick.hvac]

+1 for the thermobob.
I'm in Canada and use of an oil T-stat as well as coolant t-stat is pretty much mandatory.
Priority one is making sure oil and coolant temps are above minimums.
The thermobob bypass line goes to my heater core. Kitfox uses a Setrab 50-616-7612. PWM controller on the fans adjusts the temp (no isolation).
I have seen situations where using the heater cools down the bypass enough that I can run out of heat from the engine so that needs attention in flight.
Seal up the tail which sucks the heat out like a vacuum. I am aware of some that use an insulated divider behind the seat to keep the heat in too.