Preheater

I also leave a cube heater in the cabin w/ a t-stat cube on both products.

Doesn't it fog up/ice up as soon as you pull the plane out of the hangar?

That's what happened to me when I tried pre-heating the cabin. The heater
melted all the water that had frozen into the carpeting after the last
flight, and then when I pulled the plane out into the cold -- whoosh! It
all condensed on the windows, and instantly froze!

Took a long time sitting there with the defroster on before I could
depart... ;-(
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Say Jay, isn't it also time for the annual "To hand turn the prop or not
to
turn the prop before starting a cold engine party" ?

Nope. You absolutely, 100% convinced us all of the lunacy of THAT old
wive's tale...

:-)
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay Honeck wrote:

Doesn't it fog up/ice up as soon as you pull the plane out of the hangar?

A propane pre-heater will definitely do this. Combustion of propane produces
inordinate amounts of water vapor.

George Patterson
If you're not part of the solution, you can make a lot of money prolonging
the problem.

I have a Red Dragon that I put into a leather case (with a hole on the side
for the air output and another for the input). I also can fit 2 portable
propane bottles in the case. On the wall of the case, I put two bolts that
the power leads clip to. After that I carry a little coleman 12v power
source that clips on the bolts outside of the case.

It'll preheat maybe 5 or 10 times with the bottles and power before
recharge. I throw it in the baggage area in the winter and it weighs about
30 lbs.

It's invaluable for XC trips in the winter.

--
remove underscores to email


"Tony Roberts" wrote in message
...
Hi
I'm looking for a preheater for my 172.
I don't have a power source near my tiedown.
I don't own a generator.
Because of all of the above I'm looking for a propane powered preheater
but I can't find one.
Any recommendations? Any reason why I shouldn't buy a propane one.

Victor J. Osborne, Jr. wrote:

The Reiff is owner installable
w/ an A&P signoff.

They all are.

Roger Long om wrote:

: Remember that the cylinders are designed for efficient transfer of heat from
: metal to air and work that way in reverse. After prompting by our A&P, I
: started looking critically at oil temperature and concluded that the 20
: minute preheats we were getting from the FBO's big blower were not doing
: much for the oil deep down in the pan. There is a lot of thermal mass in
: the engine. As our A&P says, "Have you ever tried to thaw out a frozen
: turkey on Thanksgiving morning?" The oil sump is at least that massive.

I designed my own preheater a couple years aog. It's a 35,000 BTU propane
"utility" heater with some adapters and clothes drier ducts. My 12V to
120V inverter runs the fan, and my airplane footlocker holds the preheater,
inverter, propane bottle, and the wing covers (and about 4,000 other things
that I should throw out...)

I fashioned a device that plugs into the cooling air exhaust behind the
nosewheel on my Cherokee. 20 minutes of heat raises the oil temp from
0F to 50F as measured by a thermocouple attached to the dipstick.
A couple more minutes on each side of the cowling cooling air inlets to
warm the cylinders, and I'm done.

Don't forget the the electric oil sump heaters are between 250 to 500 watts,
and my propane heater is about 10,000 watts (W = 0.29 * BTU). You'd
expect 40 times the heating power to reduce warm-up times.

--
Aaron Coolidge (N9376J)

Jay Honeck wrote:
Good idea. Although (and this debate seems to happen here every year about
this time) I wonder if pre-heating, and then NOT pre-heating (without
actually flying the bird) doesn't actually generate condensation as the warm
metal cools, thus inducing corrosion?

I just let it stay warm all the time, whenever the temp drops below 35
degrees. And I usually fly twice a week.

I tend to avoid the yearly debate, but I did think about your scenario for
a while, and I came to the conclusion that it's about the same as a timer.
Consider this situation... You get a string of non-flying days where it's
30 deg at night, and 45 deg during the day. Your cube will turn the
heater on every night, and let it cool during the day. You're effectively
getting the same situation that you're trying to avoid with the timer. I
figure that turning my heater on once a week (early Saturday morning) in
anticipation of flying on Saturday will probably be a reasonable
compromise.

-- Jay

__!__
Jay and Teresa Masino ___(_)___
http://www2.ari.net/jmasino/ ! ! !

Checkout http://www.oc-adolfos.com/
for the best Italian food in Ocean City, MD and...
Checkout http://www.brolow.com/ for authentic Blues music on Delmarva

We used an electric fan heater in the planes when I was in
Stockholm. It was thermostat controlled and was on all the
time the plane was in the hangar (if the last person to fly
remembered to plug it in). No problems with misting up at
all.

Paul

"Jay Honeck" wrote in message
news:7MVpb.108620$e01.372593@attbi_s02...
I also leave a cube heater in the cabin w/ a t-stat cube on both
products.

Doesn't it fog up/ice up as soon as you pull the plane out of the hangar?

I tend to avoid the yearly debate, but I did think about your scenario for
a while, and I came to the conclusion that it's about the same as a timer.
Consider this situation... You get a string of non-flying days where it's
30 deg at night, and 45 deg during the day. Your cube will turn the
heater on every night, and let it cool during the day. You're effectively
getting the same situation that you're trying to avoid with the timer. I
figure that turning my heater on once a week (early Saturday morning) in
anticipation of flying on Saturday will probably be a reasonable
compromise.

True. Your solution probably makes sense for where you live. Your
temperature scenario only occurs around here during the fall and spring --
and I don't even have the cube plugged in yet. (Of course, right now the
plane is down, having the interior panels re-done over in Clinton -- so it's
in a heated hangar!)

In another few weeks, however, the temperatures will fall below 40, and
mostly stay there for the next 10 weeks or so. From that point on, the
heater will be on basically 24/7.

But, if we get one of those rare winter warm ups, where it jumps into the
40s or 50s, the cube takes care of shutting off the heat.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay Honeck wrote:

Of course, the rub is turning the danged thing on 3 hours in advance.
Didn't someone rig up a "cell-phone-on/off-trigger" for their pre-heater
last year?

I remember thinking it was way cool, for those who don't have a hangar
with
electricity. (If you have a hangar, the best trigger, IMHO, is the
temperature-sensitive cubes. They go "On" at 35 degrees, "Off" at 40
degrees...)

My club has been looking at preheating solutions, and I wonder if this would
fit. But there are some aspects about this solution about which I'm a
little unclear.

First, we're speaking of an electrical system that's powered by a portable
generator, right? So the "on/off" mechanism would have to switch the
generator on/off, right?

Is temperature really the right solution? I kind of like the cell-phone
idea. It seems inefficient to keep the engine warm against bitter cold
that's so bitter nobody's willing to visit the airplane.

More than inefficient, though: what about fuel for the generator? If the
generator is on for "a while", won't it eventually run out of fuel? That
would be an annoying thing to learn only when one wanted to fly and found a
cold aircraft when a warm one was expected.

Is there some commercial source for cellular on/off switches? Or did
someone ever post instructions for building one?

Thanks...

Andrew