Cabin heat solutions?

[hais]

I flew my O the other day where OAT was -23C. I tried to pull both the vent and heat on, and only heat on - nothing helped. It was so cold that I was freezing even though I had thermal layers on. I had to descend down to 12K where OAT was -11C and somewhat bearable. Next time you catch me complaining about airline X's economy cabin, remind me of this flight :). 

Questions:

1. Is this normal, or is something broken with my O?

2. If normal, do you have aftermarket solutions? 

3. Up at 16K, I was using oxygen - it was so cold it was hurting my nose. Does your built-in O2 get cold? Do you have a solution? 

[BorealOne]

I used to plug the cabin air intakes on the cowling with foam during the winter months. Made all the difference flying in Canada’s far North.

[hais]

22 minutes ago, BorealOne said:

I used to plug the cabin air intakes on the cowling with foam during the winter months. Made all the difference flying in Canada’s far North.

Thanks, will try that. Any issues with air quality or condensation with fresh air limited?

[Schllc]

I’m not sure it’s normal. 
I have been in temps close to that and I couldn’t turn the heater past two notches or everyone would be sweating. 
I would check the hoses connecting the heat exchanger, on both sides. 
the heater on the planes I have had, have definitely had excess capacity. 

[BorealOne]

4 hours ago, hais said:

Thanks, will try that. Any issues with air quality or condensation with fresh air limited?

Not at all. There was still fresh air intake - just reduced by 80% or so - and plenty of air exchange still occurs through the non-pressurized hull.  

[LANCECASPER]

Mooney made a cold weather kit for the Ovation. It's a sheet metal panel that's installed under the cowling.

[skykrawler]

On 11/25/2021 at 6:53 PM, hais said:

I flew my O the other day where OAT was -23C. I tried to pull both the vent and heat on, and only heat on - nothing helped. It was so cold that I was freezing even though I had thermal layers on. I had to descend down to 12K where OAT was -11C and somewhat bearable. Next time you catch me complaining about airline X's economy cabin, remind me of this flight :). 

Questions:

1. Is this normal, or is something broken with my O?

2. If normal, do you have aftermarket solutions? 

3. Up at 16K, I was using oxygen - it was so cold it was hurting my nose. Does your built-in O2 get cold? Do you have a solution? 

You did not say whether you had heat at all.  I've flown the J at 11500 at -30 and the heat coming from the center duct was was good and warm, but not enough to fully heat the cabin.  The fight seat passenger can put a blanket or towel next the the door to reduce drafts.

 

[hais]

5 hours ago, skykrawler said:

You did say whether you had heat at all.  I've flown the J at 11500 at -30 and the heat coming from the center duct was was good and warm, but not enough the fully heat the cabin.  The fight seat passenger can put a blanket or towel next the the door to reduce drafts.

 

The air coming out of vents was not warm at all - it was colder than the cabin ambient temperature. So I closed the vents.

[hais]

7 hours ago, LANCECASPER said:

Mooney made a cold weather kit for the Ovation. It's a sheet metal panel that's installed under the cowling.

Is that for the oil, or for the cabin? 

[LANCECASPER]

1 hour ago, hais said:

Is that for the oil, or for the cabin? 

Good point. I have one in my hangar. I'll post a picture. Oil makes more sense.

[Guest]

From the IPC, here is the oil cooler winter plate.  As for cabin heat, it doesn’t sound normal.  I’d lift the top cowl and make sure all of the ducts are connected correctly.

Clarence

[GeeBee]

I've had situations running LOP where I could not get enough cabin heat. Heck I could not keep the CHT's above 250. Switched to ROP and got the heat I needed.

 

[hypertech]

The only heat is the center floor vent.  If you have the overheads or knee vents on, you are just mixing in cold air.  Under the copilot dash is the mixing valve where the outside and heat air flappers are before being directed to the floor vent.  Open this up and look at it.  A number of them have holes cut in the flapper such that there is always outside air mixed in.  I'm told this was done at the factory out of a monoxide concern (the solution to pollution is dilution...).  Get a Sensorcon and cover those holes up with a piece of baffling or tape.  It helps but the heat for the front row is still not super duper strong.  I often wonder how people fly in the flight levels without their toes falling off.  Also, if you are flying LOP and are cold, switch to ROP, get the EGT's up and you might get more heat.

[larryb]

I’ve been at -40 degrees C and been comfortable in my encore. The heater is very effective.

I’ve never noticed the built in O2 being cold. I have an O2D2 so there is plenty no opportunity for it to warm up on the way to me.

[Guest]

If the circled valve is open, you’re diluting the hot air coming from the engine.  Of the air inlet duct on the left side of the engine cowl is not connected the air flow will be diminished to virtually nothing.

Clarence

 

[N231BN]

To drop the lower cowl on an Ovation one needs to disconnect the air inlet hose for the heater. It most likely didn't get re-connected properly the last time the cowling was installed.

[Ed Hauck]

On 11/25/2021 at 6:53 PM, hais said:

I flew my O the other day where OAT was -23C. I tried to pull both the vent and heat on, and only heat on - nothing helped. It was so cold that I was freezing even though I had thermal layers on. I had to descend down to 12K where OAT was -11C and somewhat bearable. Next time you catch me complaining about airline X's economy cabin, remind me of this flight :). 

Questions:

1. Is this normal, or is something broken with my O?

2. If normal, do you have aftermarket solutions? 

3. Up at 16K, I was using oxygen - it was so cold it was hurting my nose. Does your built-in O2 get cold? Do you have a solution? 

Not normal. Had you preheated the cabin? If so you have a heating problem. I have flown in cold conditions -15c many times and never had a problem.

[Ragsf15e]

13 hours ago, hypertech said:

The only heat is the center floor vent.  If you have the overheads or knee vents on, you are just mixing in cold air.  Under the copilot dash is the mixing valve where the outside and heat air flappers are before being directed to the floor vent.  Open this up and look at it.  A number of them have holes cut in the flapper such that there is always outside air mixed in.  I'm told this was done at the factory out of a monoxide concern (the solution to pollution is dilution...).  Get a Sensorcon and cover those holes up with a piece of baffling or tape.  It helps but the heat for the front row is still not super duper strong.  I often wonder how people fly in the flight levels without their toes falling off.  Also, if you are flying LOP and are cold, switch to ROP, get the EGT's up and you might get more heat.

I’m not doubting the LOP vs ROP heat folks, but the EGTs are higher during LOP, so I wonder why wouldn’t that increase heater output?  Higher EGTs lead to the heater muff and should yield higher heater temps, no?

[Danb]

16 hours ago, M20Doc said:

From the IPC, here is the oil cooler winter plate.  As for cabin heat, it doesn’t sound normal.  I’d lift the top cowl and make sure all of the ducts are connected correctly.

Clarence

Clarence is there a cold winter kit for Bravos as well?

[GeeBee]

1 hour ago, Ragsf15e said:

I’m not doubting the LOP vs ROP heat folks, but the EGTs are higher during LOP, so I wonder why wouldn’t that increase heater output?  Higher EGTs lead to the heater muff and should yield higher heater temps, no?

Which is burning more fuel?

[Ragsf15e]

1 hour ago, GeeBee said:

Which is burning more fuel?

Oh yeah I agree, but I would think that the heat exchanger inside the exhaust just cares about the exhaust temp.  ROP keeps the CHTs warmer but the egt is (a bit) cooler.

[Guest]

8 hours ago, Danb said:

Clarence is there a cold winter kit for Bravos as well?

Not that I’ve seen, nor is there anything listed in the IPC.

Clarence

[201er]

5 hours ago, Ragsf15e said:

Oh yeah I agree, but I would think that the heat exchanger inside the exhaust just cares about the exhaust temp.  ROP keeps the CHTs warmer but the egt is (a bit) cooler.

The hottest cabin warm air temp is not going to be ROP or LOP for that matter. It will be hottest at P.

[carusoam]

OK… Peak is good…

The flame temperature of a match is pretty hot too…

Kind of like measuring the quality of the flame…

One wants to consider the Quantity as well…

Max MP is a must… to convert as much fuel to heat as possible, in a given amount of time…

Then focus on if the heat is arriving to the cabin after that… then staying there…

Once it makes it to the cabin… is there too much cold air getting in from somewhere that it isn’t expected…

Many of The long bodies have a perfed plate for a butterfly valve, that always allows some cold air in…

a Leaky door seal can remove all of the warm air delivered to the cabin…

Really cold air at altitude is hard to combat with an NA engine…. Not enough MP…

Everything has to be working properly at max output to keep things warm… the higher up you go… on a wicked cold day…

Make sure all of the eyeball vents are closed… two up front… and four overhead…

Not being able to close off a cold air supply can become dangerous over an extended period of time….  Dying of exposure while you fly is bad piloting…  

excess cold air entering the cabin is unimpeded… the cabin always vents whatever excess comes in…

The hot air being delivered to the cabin is flowing pretty strongly… blowing very noticeably…

The temperature of the hot air being delivered… is too hot to keep your hand in front of…

+1 for having a good CO monitor…

My M20C easily ran out of heat at altitude on really cold days…

My M20R never ran out of heat up to 12.5k’…

Best regards,

-a-

[GeeBee]

20 hours ago, 201er said:

The hottest cabin warm air temp is not going to be ROP or LOP for that matter. It will be hottest at P.

True that, do you want to be there?