Aimable Heat Duct?

[ZuluZulu]

Oh no.  I'm turning into the crazy mods guy aren't I.  First the ceiling light panel, now this.  Pressing on...

Coming from trainer Pipers, I'm actually quite impressed how well my Mooney puts out heat.  It gets nice and toasty in there, which my passengers appreciate more than me, and my trusty Sensorcon helps make sure it's safe.

However, I have some notes.  The vent shoots hot air horizontally right over the top of the fuel selector.  Switching the fuel tanks every 30 minutes requires manipulating a scalding-hot metal lever.  It would also be nice to be able to aim the heat up a bit, especially toward the copilot's seat.  

Has anyone ever tried coming up with an aimable vent solution for this duct?  @DonMuncy, may I bribe you?

[carusoam]

Put that in the file for @Davidv as well... (heated fuel selector valve). 

Hot air is naturally forced over the aluminum handle of the selector valve...

Best regards,

-a-

[Hank]

2 hours ago, ZuluZulu said:

Oh no.  I'm turning into the crazy mods guy aren't I.  First the ceiling light panel, now this.  Pressing on...

Coming from trainer Pipers, I'm actually quite impressed how well my Mooney puts out heat.  It gets nice and toasty in there, which my passengers appreciate more than me, and my trusty Sensorcon helps make sure it's safe.

However, I have some notes.  The vent shoots hot air horizontally right over the top of the fuel selector.  Switching the fuel tanks every 30 minutes requires manipulating a scalding-hot metal lever.  It would also be nice to be able to aim the heat up a bit, especially toward the copilot's seat.  

Has anyone ever tried coming up with an aimable vent solution for this duct?  @DonMuncy, may I bribe you?

Let's trade Mooneys. My louvred heat vent is in the same location as yours, but my fuel selector is between my feet.

The cabin heat is so effective that even when I lived in Ohio, I generally pulled the Cabin Heat knob only halfway, and ran just about as much Cabin Vent (fresh, subfreezing air) to minimize pilot and passenger sweat. Never had a challenge switching tanks with the heat on.

Now in Alabama, I generally just use a touch of heat, because it can get cool at altitude even in summer. Maybe it's the short pants making it feel cooler? My neighbor drives his golf cart around the neighborhood in bermudas and flip flops year round, adding a windbreaker when needed . . . . .

[ZuluZulu]

1 hour ago, Hank said:

Let's trade Mooneys. My louvred heat vent is in the same location as yours, but my fuel selector is between my feet.

The cabin heat is so effective that even when I lived in Ohio, I generally pulled the Cabin Heat knob only halfway, and ran just about as much Cabin Vent (fresh, subfreezing air) to minimize pilot and passenger sweat. Never had a challenge switching tanks with the heat on.

Now in Alabama, I generally just use a touch of heat, because it can get cool at altitude even in summer. Maybe it's the short pants making it feel cooler? My neighbor drives his golf cart around the neighborhood in bermudas and flip flops year round, adding a windbreaker when needed . . . . .

My chief passenger likes it as warm as possible.  Meanwhile I'm down to just a T-shirt.  Trust me, that fuel selector gets HOT.

[jaylw314]

6 hours ago, ZuluZulu said:

Oh no.  I'm turning into the crazy mods guy aren't I.  First the ceiling light panel, now this.  Pressing on...

Coming from trainer Pipers, I'm actually quite impressed how well my Mooney puts out heat.  It gets nice and toasty in there, which my passengers appreciate more than me, and my trusty Sensorcon helps make sure it's safe.

However, I have some notes.  The vent shoots hot air horizontally right over the top of the fuel selector.  Switching the fuel tanks every 30 minutes requires manipulating a scalding-hot metal lever.  It would also be nice to be able to aim the heat up a bit, especially toward the copilot's seat.  

Has anyone ever tried coming up with an aimable vent solution for this duct?  @DonMuncy, may I bribe you?

 

I think @Hank has the right idea--open up the cold air vent as much as possible, and just open up the cabin heat as much as necessary.  Better to have a hurricane of warm air than a trickle of scalding hot air on your fuel selector handle!

 

[ZuluZulu]

Thanks for the thoughts, everyone, but the aforementioned chief passenger is not going to accept a solution that is basically "less heat."  I really meant it when I said I was looking for a way to aim the flow of air.

[Hank]

3 hours ago, ZuluZulu said:

Thanks for the thoughts, everyone, but the aforementioned chief passenger is not going to accept a solution that is basically "less heat."  I really meant it when I said I was looking for a way to aim the flow of air.

I bought my wife a small blanket, warm and fuzzy, embroidered with her name and the Vintage Mooney logo. It's about half of a regular blanket, so she actually has two. It's small enough to use in the plane and in the car. Got itmseveral years back at a pre-Christmas craft show, in a color that goes well with the seats. It allows me to reduce the heat some, but I still leave her in control of the two knobs (they are behind the right yoke anyway).

[jlunseth]

I use a glove or even a piece of paper to move the switch. When it is that cold I have a pair of bicycling gloves that will work a touch screen, and I use those for start-up, working the GTN 750, so if I really need to I can put a glove on to switch tanks, but I have found that for the brief moment you are switching, even a plain piece of paper let's you do it. I suppose you could get something made that would fit inside the heat vent, but there is nothing for it to hold onto in there, straight sheet metal. Most of the time I do what the others have suggested, mix the air. You can put the same amount of heat into the cabin with high heat at low to medium volume, as mixed air at a higher volume. However, up here in the winter it reaches the point where it just doesn't cut it. I have flown in temps so cold the windows frost over and stay that way with the heater on high and no vent, you need all you can get.

I agree, the heater is pretty good, although when the temps fall into the minus F range it doesn't always keep up. The main problem is the footwells, which are forward of the heat vent. Warm woolen socks help, and sometimes long johns, just a light pair is all that is needed.

[ZuluZulu]

Guys: I very much do appreciate the feedback, and these are good ideas to solve other problems, but my question was not "how do I make the air less hot" or "what can I use instead of the heater."  (I have blankets in the plane too.) The specific question was, what might I use to direct where the air is going.   Any ideas?  I might just buy some random pieces of metal and plastic and start experimenting.  Was hoping someone might have had the same crazy idea as me.   

[Bartman]

I would be concerned about the fuel selector being so hot you cannot touch it. Not so much because of fire risk, but deterioration of the o-rings, seals and the mechanism itself. My J has a butterfly valve that is flush with the outlet and I can completely close or use to direct up and down. It was made that way but maybe you could do something similar. I do not have a picture. 

[laytonl]

Now, to actually answer your question.   it would probably be easy to make a fiberglass angled joint to direct air upward.  Lee

[warren.huisman]

I find I get plenty of heat from the duct in the middle, but my feet freeze because the heat duct is so far back (relative to my feet).  I have wondered if something could be fabricated to direct heat forward towards my feet.

[carusoam]

Experiment away with a pair of eyeball vents and a sheet metal box...

PP thoughts only, check in with your mechanic...

Best regards,

-a-

[81X]

On 2/3/2021 at 8:47 PM, warren.huisman said:

I find I get plenty of heat from the duct in the middle, but my feet freeze because the heat duct is so far back (relative to my feet).  I have wondered if something could be fabricated to direct heat forward towards my feet.

This is the problem I have as well, icy feet when it’s really cold.  Some kind of vent directing at least some air up there sure would be nice!  

My wife will move her seat all the way back during cruise and put her feet basically in the heat vent.  Happy wife!  
 

My Cherokee 180 had vents all the way up by the firewall that would almost melt your shoes. 

[Hank]

5 minutes ago, 81X said:

This is the problem I have as well, icy feet when it’s really cold.  Some kind of vent directing at least some air up there sure would be nice!  

My wife will move her seat all the way back during cruise and put her feet basically in the heat vent.  Happy wife!  
 

My Cherokee 180 had vents all the way up by the firewall that would almost melt your shoes. 

Ya'll don't have the footwell pipe with a valve in each side of the pedestal that has to be closed to defrost the windshield or open to run heat? Sorry if it's small, I wanted parts of two pages in ine screenshot. Zoom in as needed.

[ZuluZulu]

If anyone would be interested in having one of these for themselves, please let me know.  I'm looking into it.

[Tom 4536]

On my K the fuel selector gets too hot too touch bare-handed. When I push the heat control to the closed position I still get a lot of hot air. Is this typical of the K or do I have a problem? With the heat control in the off position and the vent full open I still get warm air through the vent near the fuel selector. In the winter I need to fly with heat off, vent open. In the summer the plane is way too hot. Is it safe to just plug the heat outlet or does air need to flow through that vent to prevent the heating system from overheating. A deflector with a shutoff like used on cars would be helpful.

[jlunseth]

@Tom. No, that does not sound right. I don't know the architecture of the system, but there must necessarily be a door of some kind in the heat duct, upstream of the junction with the vent duct, to allow mixing hot air into the vent air. That is what happens in my aircraft. If I close the heat off (push the heat knob all the way in, to be clear), I get cool air at whatever the OAT is coming in through the vent. Or I can close the vent and the heat and get nothing. Sounds like something is not working correctly. However, it is true that the fuel knob gets very hot when it has heat blowing on it.

Amend that a little. I looked at my POH. There is a diagram under CABIN ENVIRONMENT. It shows fresh air being brought in through the heat tube around the muffler to warm it, and then being routed to a "mixer box" where it can be mixed with fresh air also brought it to the mixer box. There is a "hot air dump" out the bottom of the mixer box which appears to be a way to get rid of unneeded hot air. I deduce that your mixer box is not working correctly. You could probably plug the vent, but remember, that air is really hot, what do you want to use that won't get overheated or even catch fire. Not a fire expert, but I do know that there is a phenomenon where the ignition point of organic materials can be lowered significantly by long exposure to high heat. Pyrophoric carbonization. I would have your A&P fix your mixer box, safer and then you get to choose heat versus ambient air.

[Tom 4536]

19 minutes ago, jlunseth said:

@Tom. No, that does not sound right. I don't know the architecture of the system, but there must necessarily be a door of some kind in the heat duct, upstream of the junction with the vent duct, to allow mixing hot air into the vent air. That is what happens in my aircraft. If I close the heat off (push the heat knob all the way in, to be clear), I get cool air at whatever the OAT is coming in through the vent. Or I can close the vent and the heat and get nothing. Sounds like something is not working correctly. However, it is true that the fuel knob gets very hot when it has heat blowing on it.

Amend that a little. I looked at my POH. There is a diagram under CABIN ENVIRONMENT. It shows fresh air being brought in through the heat tube around the muffler to warm it, and then being routed to a "mixer box" where it can be mixed with fresh air also brought it to the mixer box. There is a "hot air dump" out the bottom of the mixer box which appears to be a way to get rid of unneeded hot air. I deduce that your mixer box is not working correctly. You could probably plug the vent, but remember, that air is really hot, what do you want to use that won't get overheated or even catch fire. Not a fire expert, but I do know that there is a phenomenon where the ignition point of organic materials can be lowered significantly by long exposure to high heat. Pyrophoric carbonization. I would have your A&P fix your mixer box, safer and then you get to choose heat versus ambient air.

Good to hear that I am suppose to get cool air when the heat is shut off. My annual is coming up and I will have the mixing box looked at. Thanks

[81X]

6 hours ago, Tom 4536 said:

Good to hear that I am suppose to get cool air when the heat is shut off. My annual is coming up and I will have the mixing box looked at. Thanks

I think you’re supposed to get no air when the vent and heat levers are both in. That’s the way it is in my K. 

[Tom 4536]

Thanks for the info. I get warm air with both closed so something is wrong.

[carusoam]

Tom,

Sound like the hot air valve isn’t closing fully...

or your Tucson cold air is the same temp as the NJ hot air.... 

One of the air valves (some Mooneys) doesn’t close completely, for a reason... 

But, I don’t think it is the hot air... that would make it tough on really hot days, knowing more heat was coming in the cabin...

Look into the air valves in the cabin air system... some have a butterfly valve with rubber seals...  might be time for an upgrade...

PP thoughts only, not a mechanic...

Best regards,

-a-

 

[David Lloyd]

Half the older Mooneys with the fuel selector valve between the knees have a PVC T handle sliding around on the floor.  It is used by us, older, non-flexible types to reach and turn the fuel selector.  Apparently it is needed in newer Mooneys during the winter months.

[skykrawler]

The muffler is at the bottom.

 

[Tom 4536]

That is a great diagram. Looks like my culprit is the gate that shuts off the air from the muffler.

Thank you.