Author Topic: Exhaust Sys & Htrs  (Read 9630 times)

Doug Johnson

Exhaust Sys & Htrs
« on: November 26, 2011, 04:36:52 PM »
I don't know about anyone else, but the few times I flew at -40 I had trouble staying warm and the one time I carried a passenger in the rear at that temp she practically froze, in fact we landed enroute to switch passenger positions.

I put a second muff on the other side and intended to run a duct under the floor to the rear seat but it never got completely figured out. If I remember correctly I was having problems going under the floor so I was looking at a plastic or fiberglass oval duct about 6"X1/2" that laid beween the seat on top of the floor. That project barely got started.

I do remember I had problems finding the exhaust pipe for the other side that was set up for a heater muff. so when I found this I thought I would post it.

I did get the combination insulating and sound deadening material completely installed but never found out if helped enough to eliminate the need for a rear seat heater. I put 2" of sound barrier on the firewall, 1 1/4" on the floor 3/4" on the rest including in the doors and the rear bulkhead and overhead above the headliner on the outer skin.

Doug

For larger view open attachments.



« Last Edit: November 26, 2011, 04:52:49 PM by Doug Johnson »
Doug

Delcourt Aviation

Re: Exhaust Sys & Htrs
« Reply #1 on: November 26, 2011, 07:24:47 PM »
I saw a GO480 on a non Helio aircraft a few years ago that used the same exhaust as a 295 so I dont see why this wouldnt work for the Helio crowd. They had welded additional flanges on the exhaust bracketing the aft cylinder risers on either side of the engine. They then fabricated new heater shrouds to fit these new flanges and plumbed the hot air to additional firewall fittings they had installed. The owners, who were from Alaska and knew about cold weather flying, stated that this mod turned the plane into a very comfortable winter flier.

                                                                                                                                                                                David

Ken Berger

Re: Exhaust Sys & Htrs
« Reply #2 on: November 27, 2011, 06:38:20 PM »
I find that my H-295 runs too hot for general flying here in the Pacific Northwest, especially in the front seats.

The ad below to the Acorn Welding is of interest to me because I haven't seen the heat muffs for sale.  I had a devil of a time finding heat muffs about three years ago and sure would have liked another source, especially if their prices are reasonable.
Ken

Doug Johnson

Re: Exhaust Sys & Htrs
« Reply #3 on: November 29, 2011, 05:10:45 PM »
I find that my H-295 runs too hot for general flying here in the Pacific Northwest, especially in the front seats.

The part about especially in the front seats, was why I wanted a separate duct going to the back seat. I had noticed at around -20 that if you got it comfortable wearing your cold weather gear that the back of your neck got cold and if anyone was in the back seat they had better be dressed as if they were outside on a calm day.

I had another concern as well, and that was maintaining a fireproof firewall when I looked at my heater I realized that I had a 3" hole in it with only a little thin piece of aluminum in front of it. All that work I'd done to keep the firewall fireproof did little with this big hole for the heater.
 
I mentioned this to David and he told me the Cessna had a pretty nice heater but it has a rubber flapper that isn't fire proof. The best one in his opinion is the system that Maules use. They don't use rubber seals and have a sliding door the totally shuts off the air from the engine compartment and if duplicated in stainless would be fireproof.

Anyone have a picture of a Maul Heater. I have a picture of a heater in a Branham helio that I was looking at not what I wanted but it was good for ideas it looked like it used two seperate heat muffs.
Doug

Delcourt Aviation

Re: Exhaust Sys & Htrs
« Reply #4 on: November 29, 2011, 07:26:20 PM »
I like the American Champion design as well, few moving parts, no rubber, and if you made it out of stainless it would be pretty nice. Another option if you want to go hog wild is a combustion heater like the one from C+D Associates. Plenty of room in the tail for the heater. It would eliminate relying on the engine for heat. I have put them in under field approvals for aircraft that didnt come with one. The Cessna 195 and 170 use them and the Helio cabin is larger than those. The C+D model does not have AD problems like the old Southwing or Janitrol units. Preheating the cabin before start up is pretty comfy...

Ken Berger

Re: Exhaust Sys & Htrs
« Reply #5 on: November 29, 2011, 11:38:36 PM »
Don't all H-295s have a heat tube and vent going to the rear?  Mine sure does.  It goes from the bottom of the firewall with a stainless sliding door along the belly under the floorboards and then up to a vent pointed back at the rear center of the two front seats.

Is there a desire to get heat even further back?
Ken

Doug Johnson

Re: Exhaust Sys & Htrs
« Reply #6 on: November 30, 2011, 07:25:12 AM »
Ken,
C/n 1233 certainly didn't have the tube you speak of and the few other Helio's that I was able to look under the floor boards I certainly didn't notice one at the time. What you speak of is what I wanted to do. But didn't see  a good route. I only wanted heat to the middle seat area because I only had a passenger in the sling seat once in the winter in 8 yrs.

I hope you have pictures if not maybe when you do your next annual you can take some.

Was this possibly a series 1400 option I wasn't aware of.

For preheating the cabin I had a 1500 watt infrared Automotive preheater you used to be able to get those at most any automotive store in Alaska. I had a Tanis preheat system with a heat pad on oil pan and batteries and cylinder htrs on a timer. I had the cabin preheat wired to plug into that, I would go out the night before and set it to turn on a couple hrs before it was time to fly.

In my winter emergency gear I carried a couple of Gasoline Blowtorches and and a length of stove pipe. I still have a brand new one that's never been used.

Doug
Doug

Delcourt Aviation

Re: Exhaust Sys & Htrs
« Reply #7 on: November 30, 2011, 11:28:29 AM »
One thing that is very common up here, and something we have done to N295SC, is modify the rear heat that Mr. Berger is refering to. We installed a flange coming out of the floor and installed a 4 foot length of SCAT tubing so whoever is in the rear of the plane can put the heat wherever they want, such as window defrosting, etc....David.

Ken Berger

Re: Exhaust Sys & Htrs
« Reply #8 on: December 04, 2011, 09:10:31 PM »
Here is a photo of the heater vent that puts heat to the middle row of seats of my 1400 series H-295.  This does not seem to be in the parts manual, but clearly was factory installed because there was a pull control cable for the vent in my original instrument panel and the slide gate is identical in design to all the other vent slide gates.
Ken

mcslo

Re: Exhaust Sys & Htrs
« Reply #9 on: December 18, 2011, 08:48:38 PM »
My 1400 has the tube and duct control up by the firewall that connects to a scat tube the runs to the center, aft edge, of the front floor board.  When I got the plane, the tube was just kind of laying there... I ended replicating the output vent.  I'll see if I can find a couple of pics of it. Here is a similar one (I don't think it's in a Helio) but same idea.

Doug Johnson

Re: Exhaust Sys & Htrs
« Reply #10 on: December 19, 2011, 05:29:59 PM »
My Helio was the last 1200 built before the U-10D contract and there was no scat tube going to the rear seats. I was upgrading to a 1400 and if I had seen one of those heaters to copy I sure would have copied it.

I imagine there must be a few more Helios without backseat heat.

Just out of curiosity I would like to see pictures of the routing under the floor and control box arrangement at the firewall.

Doug
Doug

Delcourt Aviation

Re: Exhaust Sys & Htrs
« Reply #11 on: December 19, 2011, 06:05:57 PM »
Hey Doug, if you have a fax I can send you the civilian and military parts catalog break down.


Doug Johnson

Re: Exhaust Sys & Htrs
« Reply #12 on: December 19, 2011, 11:42:24 PM »
Unfortunately I don't have a fax. I have a scanner that I used to use in place of a fax but it won't work any longer since I've upgraded the latest version of windows.
 
I also used to have an H-295 parts catalog with all the exploded views and a U-10D repair manual and parts catalog. I could never get anything for the 1400 series. When I sold my Helio I let the Parts catalogs and manuals go with it.

I hope you are not implying that I was overlooking a backseat heater in one of the manuals that I had. If I was let me know.

Are any of these manuals available on CD?
Doug

Delcourt Aviation

Re: Exhaust Sys & Htrs
« Reply #13 on: December 20, 2011, 11:07:50 AM »
Sorry, I'm not smart enough to imply anything.......I'm sure you didnt overlook anything. As far as I know, none of this is available on CD. The only source I can think of is Essco, and those are only reprints of the originals. I'm sure I'm not the only one who wishes the current owner of the Type Certificate would do something with it.


Doug Johnson

Re: Exhaust Sys & Htrs
« Reply #14 on: December 20, 2011, 07:18:45 PM »
Seriously, was I overlooking a backseat heater in one of the parts manuals?

I wish someone would turn loose of a copy of the Helio mods.

Doug
Doug