Janitrol heater

[Paul462]

Yeah, you're right - there probably aren't that many crashes caused by combustion heater malfunctions. Maybe it's the psychological aversion to the scenario - drifting peacefully off to sleep under the influence of carbon monoxide somehow doesn't seem as bad.

Of course, electric heaters risk electrical fire, and muff heaters risk carbon monoxide poisoning (although a good digital read-out carbon monoxide meter with alarm would mitigate that risk). I wonder how these three heater options compare in terms of crashes per 100,000 hours flown? Maybe combustion heaters are actually safer than muff-type heaters?

[rmorris]

Sorry, but I just don't understand the thinking by Cessna engineers, nor why no one has made a modification through field approval or STC to remedy it.

The reason a combustion heater is necessary on most twins is simple - the engines are out hanging under the wings, so very inefficient to try and pipe that excess heat through an exhanger into the cabin. Our engines are not out under the wings- we have one right in front of us - just a like a single engine design.

On single engine airplances it is a simple process to set-up a heat exchanger type system, no extra fuel or flame needed, to get heat into the cabin. You still have to have proper carbon monoxide detectors and sound exhaust system checks done under any system. Why not just heat the Skymaster the way a single engine plane does it?

Has anyone ever tried to use a mod that gets nice engine heat into the cabin and eliminates the combustion heater?
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Washington Dispensaries

[hharney]

The normal aspirated Skymaster has the heat exchanger feature. Only the Turbo and the P models use the combustion heater.

[rmorris]

Originally Posted by hharney

The normal aspirated Skymaster has the heat exchanger feature. Only the Turbo and the P models use the combustion heater.

I'm ?? guessing ?? it has to do with trying to heat exchange at flight levels, but what about lower? Seems that the turbo should be able to be set-up with a heat exhanger and then switch over to combustion if for some reason you get high and exchanger doesn't function.

Anyone out there ever tried to set up a turbo or p with heat exchanger type heat in lieu or in addition to the combustion model?
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Puma

[JeffAxel]

Originally Posted by rmorris

I'm ?? guessing ?? it has to do with trying to heat exchange at flight levels, but what about lower? Seems that the turbo should be able to be set-up with a heat exhanger and then switch over to combustion if for some reason you get high and exchanger doesn't function.

Anyone out there ever tried to set up a turbo or p with heat exchanger type heat in lieu or in addition to the combustion model?

never tried this, but the P210 uses heat off the exhaust thru a heat exchanger. Worked fine down to -30 or so in my experience. Simple and lightweight. I wonder why Cessna didn't change to this on the later models?? The C&D heater works well though.

[Kim Geyer]

The T337H has a heat exchanger and only uses the heat from 2 cylinders. I guess it works good because the pilots don't whine about being cold.
Kim

[Paul Sharp]

I replaced the heater in my T337B two years ago with an O/H'd one from Janitrol ("Kelly Aerospace" now) and it was just under $2K through Harold Haskins (Dothan, AL). It was a totally new core and parts so while it was an "overhauled" heater it really is new now. I pulled the old one out and put the new one in and then my A&P's finished up one dififcult part of the process that was giving me some trouble and signed it off (less than $200). I spent half a day getting it out and half a day getting the new one back in. For certain steps of the in and out process it was really a 2-man job, and I had a good friend help for a couple of hours.

I can't get too excited over that endlessly quoted line "why light a fire" in the airplane for heating stuff. The heater works fine, it does the job, and if the other type had worked well at the time they designed the T's and P's I suspect they'd have used that instead. My A/C is certificated to 33K feet, and it needs a good heater when you get high and cold.

[rmorris]

Originally Posted by Kim Geyer

The T337H has a heat exchanger and only uses the heat from 2 cylinders. I guess it works good because the pilots don't whine about being cold.
Kim

Kim,
You suppose there is a way to convert to the 337H set-up and eliminate the Janitrol heater?
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NASH 600 SPECIFICATIONS