Cockpit Heating

Kitfoxes use a coolant radiator and fan for cabin heat.

Sean Griffin wrote:

"The liquid heater core ones under the instrument panel are impossible to bleed the air out as they are highest point of the liquid cooling system, terrible design and prone to getting air trapped."

Impossible? More likly a doable pain in the rear, that only occurs about every 2-5 years - on a par with the 5 year rubber replacement.

If the occasional  bleedings of the system is the only negative, there must be a host of positives - do tell?😈

And if one used teflon lines instead of rubber, as I did, it's even less of an issue.

All

Rotax only states use of hot airbox (Rotax supplied) for carb heat.  The use of any cabin heating system is up to the OEM or builder.  The conventional systems in piston aircraft are exhaust heated air directed to the cabin via a duct and control butterfly, similar to air cooled engines.  Many Rotax powered aircraft have used hot coolant passed into a controlled small heater core with a 12 volt fan.  The design is not specified by Rotax and would be something each OEM or builder would have to confirm suits the aircraft type.  

Pros of exhaust heat type, fast heating, engine cooling air flows without a fan.  ( in most cases)   Cons, risk of CO2 issues with any bleed air or cracks. Complex installations. 

Pros of coolant heat type, no risk of exhaust CO2 issues.  Cons, may not heat up fast enough for some users. Hose plumbing and airflow.  Use of a fan mandatory for heat to circulate. 

Your pick really. Just my opinion. 

Cheers

With the coolant (or oil) based heating systems, is there the potential for engine overcooling that must be managed? and if so how?😈

Hi Mike,

"And if one used teflon lines instead of rubber,...."

How does "Teflon" hose make the job of air removal (bleeding) any easier? 😈