Heater Output for Ranger

[Chessieretriever]

Hallo Folks,

A couple of weeks ago we travelled from Houma, LA to Mount Pocono, PA direct with our little Ranger. We filed and got 17,000ft (Rajay Turbo) and were doing great until the temperatures dropped to the point of freezing the two of flying. The heater could not keep up with the heat loss to ~10F OAT. We had to decend to 11,000ft to continue due to human temperature limitations (see http://flightaware.com/live/flight/N92AV/history/20111209/1601Z/KHUM/KMPO). Does anyone make a more powerfull heater for this bird? I find the efficiency/speed combination of our little backup plane unbeatable even compared to our Rocket. Please advise if you know of something that allows us to fly N92AV more in the colder months of the year.

Cheers/O

N92AV and N9154W

[Hank]

I've flown my regular O-360-powered Ranger without any heat problems at all, other than making myself too hot. My lowest departure so far was 8ºF, but I didn't think to check the OAT after climbout. I've also gone into Arnold Palmer in winter, arriving after dark for supper, only to find the ramp freshly plowed and the snow 8' or more deep. Even my wife was warm, and I think we took our coats off enroute due to temperature. Often we use about halfway on Cabin Heat, with the fresh air vent cracked to cool it off some.

So I hate to say it, but methinks you have a problem. Did you make sure all outside vents were closed? the scoop, the footwell vents, the cabin air knob, and the big lever under the throttle quadrant? Are your heat vents inboard open? There are valves there that if closed will direct heat to the windshield for defrost, one on each side of the center. Mine are black, nice and easy to see under the panel. :-)

[Guest]

Yip, mine is a cooker to.   -11 F 

[Z W]

Same with mine, down to 0 degrees F.  Check your fresh air vents - especially the overhead.

[Hank]

It could also be a defective/cracked heater box under the cowling, or a broken/disconnected/torn hose from the heat box to the firewall.

You should have LOTS  of heat!

[N33GG]

Ditto... my 68C will run you out of the cockpit.

[Shadrach]

The center vent on my F would literally burn you if you left your hand in front of it with full heat applied.  I suspect that the there is an issue with the heat exchanger. I'm not familiar with the RayJay set up, but I'd start with the exchanger.

BTW, 1,100mile in under 5.5hours is pretty sweet...

[jwilkins]

When I bought my first Mooney ('62 M20C) the seller (from Alabama) kept a blanket and a piece of flexible 3 inch plastic dryer vent in the plane for his wife. She would bundle up in the blanket, put one end of the heater hose on the heater output and stick the other end under the blanket.

Moving the plane to upstate NY I needed a better heating solution. We did the following:

1. Replaced the door seal (helped a little)

2. Replaced the missing aluminum tape on the spar behind the seats, the various opening inside the nose wheel well, on the firewall seams to the nose gear housing, and under the side panels. Over the years the tape had been removed for inspections, or just fallen off and had not been replaced. This produced a significant difference in keeping the cabin warmer. The area behind the seats over the spar is supposed to be taped up to reduce air infiltration. There was residue showing where the tape had been, but no tape.

3. Replaced the rudder pedal control rod boots. This made a huge difference. The front of the boots were torn out and acting just like fresh air vents. If you looked at them the boots looked OK but they were completely open towards the firewall. I bought some inexpensive leather scraps from a local shop so that I would not have to find certified FAA certified material for fire burn. The new boots were fairly easy to sew up, but a real pain to install with the very small screws around the perimeter.  I recently found the cardboard pattern for the boots if anyone would like it so you can perhaps make the new boots before you remove the old ones.

4. Checked to make sure the cables were adjusted properly to open the heat door vent. A slight adjustment was made to open the door completely. We couldn't tell any difference.

After all this the heater would heat the cabin too much if you did not add significant cold cabin air to the heater air. 

Having said this, my C did not have a Turbo charger. If you check the comments about the M20 Turbo kits, one frequent comment was that the early kits resulted in poor cabin heat. I do not rememebr any comments about Ray Jay conversions so I do not know if the same issue applies.

 

Jim

 

 

[jwilkins]

I forgot about the radio stack cooling vent...

On the '62 C the co-pilot vent had a control that would open the vent to originally provide air to the radio stack. Sometime over the years the 1 inch hose to the radio stack had been relocated to make an additional vent for the co-pilot. There was a lever up under the panel (just inside from the vent) that could be used to close off the vent for the winter. It was not easy to get to, and not marked for open / closed, but you sure knew if it was open in the winter.

One time after cleaning up the seals and boots I left Bedford MA in -15F. We plugged in the sump heater, had the FBO preheat the engine, and put a quart of oil in boiling water to heat it up before adding it to the engine, as well as heating the cabin with a small electric heater to get the instruments warmed up. I followed the very cold start instructions in the POH, including flipping the prop over by hand. The engine started immediately, ran great, and the heater kept the cabin cozy warm back to KSDC. I don't remember the OAT at cruise, but I do remember the cabin was nice and warm.

Jim

 

[Mooneymite]

Two parts of the problem: is there enough heat coming in, or is there too much leakage?

When it comes to the "enough heat" part of the question, I had a Mooneymite that had a very weak heater. The Mooneymite crowd told me the fix was to take the heater box apart and wrap a "screen door spring" (yes, like you get at a hardware store) around the exhaust pipe thus increasing the heated surface area inside the heater box.

Obviously, this is not an "approved" fix, but something similar might increase the efficiency of your heater if you can figure out how to make it legal.

And if you work for the FAA, I have no first hand knowledge of any of this!

[KSMooniac]

I've had my J at -20 deg in high altitude cruise and had ample heat in the cabin.  I suspect the Rajay mod results in a less-capable heat exchanger.  Is there still a muffler in the exhaust system?  I've also read of a similar complaint with the M-20 system, and there is or were supposed to be a fix made for that, but I don't know what it might be.

You might consider a small electric heater that can be run from the 12V outlet, assuming it won't draw too much current.

[Rocket_Driver]

Quote: Chessieretriever

Hallo Folks,

A couple of weeks ago we travelled from Houma, LA to Mount Pocono, PA direct with our little Ranger. We filed and got 17,000ft (Rajay Turbo) and were doing great until the temperatures dropped to the point of freezing the two of flying. The heater could not keep up with the heat loss to ~10F OAT. We had to decend to 11,000ft to continue due to human temperature limitations (see http://flightaware.com/live/flight/N92AV/history/20111209/1601Z/KHUM/KMPO). Does anyone make a more powerfull heater for this bird? I find the efficiency/speed combination of our little backup plane unbeatable even compared to our Rocket. Please advise if you know of something that allows us to fly N92AV more in the colder months of the year.

Cheers/O

N92AV and N9154W

[rob]

I flew from Memphis to Wichita today in my 65 M20C and at 6000' the OAT was about -13C. My heater wasn't keeping up either. There are definitely some places where air is coming in, but the bulk of the issue seems to be a lack of heat. The air coming from the vents was warm enough, but the flow of it wasn't very strong. I've looked at the parts manual, and I'm a bit at a loss for why this would happen.

A flight shortly after in a similar E model demonstrated that my heat isn't up to snuff. Any suggestions on what to check?

[jetdriven]

make sure that slide valve on the firewall opens fully.  Make sure the SCAT or SCEET tubing from the muffler is good-no leaks.   Our J BLASTS air out the coneter console vent.  Cracking it open makes it 100 degrees.  Full heat would probably melt the interior plastic.

[Hank]

Pulling the Cabin Heat knob in my C opens the slider around the muffler; to actually get warm air into the cabin requires opening the vent below the throttle quadrant. Warm air comes out there [a lot!]. There are also two pipes under the panel, one on each side, with individual shut-off valves. Closing these valves sends the hot air up to the windshield as defroster; open them to heat the inside knees of both front seats.

I typically run the Cabin Heat knob 1/2-2/3 open, and the Cabin Vent knob beside it 1/4-1/2 open to modulate the temperature. Even here in Ohio in the winter. Closing the vent slider below the throttle quadrant [next to the Carb Heat] greatly reduces the flow of warm air, down to a trickle. Opening it all the way will run us out of the plane.

[rob]

Quote: Hank

Pulling the Cabin Heat knob in my C opens the slider around the muffler; to actually get warm air into the cabin requires opening the vent below the throttle quadrant. Warm air comes out there [a lot!]. There are also two pipes under the panel, one on each side, with individual shut-off valves. Closing these valves sends the hot air up to the windshield as defroster; open them to heat the inside knees of both front seats.

I typically run the Cabin Heat knob 1/2-2/3 open, and the Cabin Vent knob beside it 1/4-1/2 open to modulate the temperature. Even here in Ohio in the winter. Closing the vent slider below the throttle quadrant [next to the Carb Heat] greatly reduces the flow of warm air, down to a trickle. Opening it all the way will run us out of the plane.

[Hank]

Here's a picture of the other control; the Cabin Heat and Cabin Vent knobs are both on the panel.

No, I can't read the labels, either. The slider on the left is Carb Heat--it is Up for OFF. In this photo, the other vent knob is on the right, and it's all the way Down for CLOSED. Raise it up some, and if the Cabin Heat knob is pulled out, lots of very warm air will begin to gush out just above it.

Don't know how the earlier C's are done, but this is my '70 model. Johnson-bar-equipped planes will necessarily be different, as it will be in the way of this.

[JaredDavis]

Rob,

Does page 10 of the 65C POH help?

I'm not sure how my deflectors are set.

(Please excuse the typos)

"Cabin heat is obtained from a muff which surrounds the engine exhaust manifold. From this muff, a flexible duct transmits heated air to a junction box on the aft side of the firewall on the copilot's side. Cool air is also ducted to this junction box from the flush air scoop on the right side of the plane. The warm and cool air entering the junction box can be individually controlled to provide the combination required for the desired temperature. From the junction box, air is ducted to the pilot and copilot's feet, windsheild defroster, rear passengers' feet, and to the baggage compartment.

Deflectors are provided on the pilot and copilot outlets which can be used to direct the air flow in the desired direction or to provide individual volume controls. When these deflectors are in the neutral or "off" position, the air flow is forced to the windshield defrosters and to the aft outlets.

"

Jared

65 C

[rob]

That's basically my understanding of how it works. I'll just have to track down why there isn't more pressure forcing the air out of the vents. I do believe that someone has removed the aft outlets in my particular system...