Cabin Heat for Aerovee

[mike.smith]

Back in 2015 I started a thread about getting heat from the Aerovee to the cabin. I have been through several iterations of a single heat muff on the exhaust (with various materials inside), and various inlet/outlet sizes. Nothing has worked. I get zero heat coming into the cabin. I've heard 1 or 2 people indicate they have heat that works, but I've never actually seen any photos or web pages that show such a thing. If anyone has a WORKING cabin heater that draws heat from an Aerovee (or other VW) I would really love to see some photos and explanations. At this point, ideas are not so helpful; I'm hoping to get information about a working system.

Thanks,

[MichaelFarley56]

Mike,

I haven’t started installing it yet, but I do have the Airward exhaust heat shroud that I’m planning on installing in the next few weeks. Like you, I’m hoping to get at least some engine heat through the system to make winter flying more tolerable. My father’s homebuilt has a nearly identical setup and it will heat his cabin very well, so I remain a little optimistic something will work.

If you were to guess, do you think it’s an airflow issue through the system or simply a lack of sufficient heat being generated? I’d like to think that, even on our smaller aerovees, there’s sufficient heat from the exhaust pipes to give some cabin heat!

Do you have any pictures of your setup, such as where you installed the divider box on the firewall and how you ran SCAT hoses?

Don’t give up; I’ve been talking to a Hummelbird H5 owner in northern Michigan and he gets great cabin heat from a VW engine the same size as ours. His claim is there needs to be proper airflow exiting the cabin which will draw air through the heating system. An interesting theory at least!

[mike.smith]

If you were to guess, do you think it’s an airflow issue through the system or simply a lack of sufficient heat being generated? I’d like to think that, even on our smaller aerovees, there’s sufficient heat from the exhaust pipes to give some cabin heat!

Do you have any pictures of your setup, such as where you installed the divider box on the firewall and how you ran SCAT hoses?

Don’t give up; I’ve been talking to a Hummelbird H5 owner in northern Michigan and he gets great cabin heat from a VW engine the same size as ours. His claim is there needs to be proper airflow exiting the cabin which will draw air through the heating system. An interesting theory at least!

I've only heard rumors of a working VW heater; never ever seen one.

Anything is possible, but I've spent 4 years experimenting. I have tried all sorts of air flow configurations, minimizing and maximizing intake and outflow orifices, trying different materials inside the muff, etc. Nothing seems to work. That's why I don't think "ideas" helpful anymore. Only a demonstrable functioning system would convince me I'm not chasing a non-existent Sasquatch.

[lutorm]

An 80hp engine puts out about 80hp = 60kW of heat through the exhaust. That is a crapload of heat, so the problem can't be "not enough heat available", it has to be in how the heat is extracted. It's possible the exhaust needs to be routed through a more efficient heat exchanger than just a straight pipe.

[Gordon]

More Heat..........?

A question I have is.......how are you guys feeding the heat muff?

With the RV's.....mine included....I riveted a 2" flange to the back side of the back baffle, then a Scat hose feeding the heat muff. At 180 mph cruise it pumped a lot air through the system. On my RV-6 I had 2 heat muffs, one on each side, it worked pretty well...I live in Canada. In the summer I removed the one muff and blocked off that inlet.

The other issue may be the air is just not hot enough.
Aircraft Spruce sells a "Turbo Heat Cabin Heat Muff" p/n 05-15249. This is a "quality piece", the can is .063 and it has 10 internal heat transfer tubes. This WILL give you hotter air.

Gordon.........Hummel 2400......Onex

[lutorm]

I know the canard guys also put an oil cooler inside the cabin and blow air through it... That's of course heavier, more complex, and puts pressurized hot oil near your body, but it's a pretty efficient way of getting heat into the cabin.

[WesRagle]

Hi Guys,

My thoughts. The standard cabin heat solution has three draw backs.

1) The cooling drag generated by taking on cabin heat air is always present whether cabin heat is needed or not.
2) During warm weather, when cylinder head cooling is needed most, cabin heat air is generally dumped in the low pressure area of the cowl reducing cylinder head cooling.
3) Not enough heat.

On Sonex #664 I mounted an oil cooler to the engine side of the firewall with top and bottom plenums fabricated from 0.025 aluminum. The plan was to route the output air from the oil cooler to a heat muff and then on to the cockpit for cabin heat. As it turned out I didn't need the heat muff. The heat from the oil cooler alone was enough temperature and volume for OAT down to about 20 Deg. F. That's as cold as I ever flew here in north central Texas.

So, for extreme cold, perhaps the oil cooler to heat muff setup would be a viable solution. As a bonus your airplane will be faster due to re-purposing cooling drag you already incur.

YMMV

[pappas]

This is an old thread but I thought I would put this up for anyone else that may be looking for cabin heat.

I called Dave at custom Welding Products in Las Vegas. He makes a line of heat muffs that he markets through Aircraft Spruce. The aerovee exhaust pipes are aviation non-standard so I asked if he could make up a muff for the turbo on my Waiex B. Sure enough, it was in the mailbox a week later.

I installed it using a Stainless heat valve with an, inside the cabin, cable attachment, also from spruce. I was thinking that such a small short heat muff on such a small exhaust pipe would probably be anemic but it gets cold in the winter at 9,000 feet so I figured I would try it.

Holy cow! This thing puts out so much heat that I don't pull the cabin heat cable out more than 3/4 of an inch! I adjusted the opening in the back of the engine baffles to 1/4 the size I thought it would take to get good flow.

If you guys want heat....your search is over.

www.customweldingproducts.com

Lou Pappas
Glendale, AZ
Waiex B turbo....among others.

[mike.smith]

If you have any pictures of your installation I'd love to see them. I took my heat muff and scat tubing out this past summer since I never got an ounce of useful heat even after many designs. How much did the muff cost?

[GraemeSmith]

Encouraged by Mike a couple of weeks ago to not waste too much time on this - and with remembrances of the lack of heat in our childhood VW Bug....

So far my solution is long johns and a new pair of flannel lined pants, an extra memory foam pillow to sit on (Job Lot - open package, slightly dirty pillow - $2) and taking my shoes off. In straight and level with the plane trimmed out - I can slip my feet under the rudder pedals and rest them on the warm firewall.

I did notice Mike sporting one of those electrically heated jackets.

--

Also seriously interested in pictures of Lou's installation.