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Heater question

bob888

Well Known Member
It seems the main problem people have with heater on the RV10 is too much heat. If so, is there a mixing chamber that has a control to allow mixing cooler air into the system like I have seen on some production planes? Has anyone a different solution?
 


A couple of possibilities.

It all depends how high you want to fly and in how cold of outside airtemps you want to fly in..

On my IO 540 Rocket, during the summer, I remove the outer skin from the heat muff and bypass the heat muff totally with the heater air coming directly from the aft engine baffle direct to the firewall. This is lots of heat right up to 12K in the summer for me. If you do this you MUST remove the outer skin from the heat muff, otherwise your exhaust will over heat inside the muff section. You might not even need a heat muff at all using this method, depending on where you fly and how high. The last oil change before winter I put the muff skin back on and re plumb the scat tube through the muff.


Alternatively, you can use oil cooler dump side air and this does two things. One it restricts flow to the oil cooler in colder ambient air temps, like most of us need to do to fly in the winter months, to keep out oil temps at 185 or above. It also reduces cooling drag losses.

When you need more oil cooling in the summer you do not need cockpit heat, and are then just dumping the oil cooler heat as normal, out the cowl exit.

Ask G IKON to post a photo of his setup from his RV 4 in the UK.

Best Of Luck!
 
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I have no issues with the heat in my -10 during summer flying. I used the aftermarket SS heat-valve boxes which seem to seal up pretty good when closed.
 
My experience is you can crack the heat open just a little and open air vents to do the fine adjustments if needed. Non issue imo.
 
This may give you some ideas-----------

http://www.nwacaptain.com/heatcool.html

We put one of these on my buddies Cozy MKIV. I don't care for it simply because the "cool" air is coming from inside the cowling. It doesn't seem to bother my buddy but I get nauseous after a while from the smell of the engine compartment. I think it would be great to install a NACA on the cowling and use 2" Sceet for the cool fresh air intake of the mixer.
 
I've talked with many of the early RV-10 builders about tunnel heat issues in their RV-10. I did line my tunnel with fiberfrax and I do have carpet covering the tunnel. I've not experienced any tunnel heat issues that others have experienced. It may be because I have insulation on both the inside and outside of the tunnel.

The nice thing is on days like we've been experiencing, I can wear a t-shirt and shorts and be comfortable flying in the cabin. The problem is that I would probably freeze to death, before I can pull the RV-10 out and get the engine started. I typically open the front about 1/8"-1/4" and the back about 1/2" when flying with two people. With people in the back, I've got to close the back down to about 1/4"
 
My solution was to install a single heat valve, driven from one heat shroud. The second shroud is removed from the muffler. The installed valve supplies heat to the rear outlet, which is actually under the front seats, and gives us plenty of heat at altitude with surface temperatures down to about 30 F. Below that, you will need to bundle up a bit, but no big deal, and I don't fly that much when the temp. is a lot below freezing. I have a layer of fiberfax as a thermal break between the valve and firewall, and no issues with a hot tunnel.

The traditional approach to cabin heat just doesn't sit well with me.....we rob cooling air from the engine, and most of the time just throw it overboard, creating excess drag. In the RV-10 with dual heat valves, the flow conflicts and waste heat gets bounced right onto the fuel pump on it way out of the cowl. There are so many things wrong here. With one valve, you are wasting some cooling air in summer, but less, and with one valve you aren't throwing heat onto the fuel pump. Less scat hose back there helps with access, and might help in accelerating the flow out of the cowl too. The more I think about it, I may take off the one heat muff I have, and just dress warm!
 
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