Wanted: Heat!
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Wanted: Heat!
I have been reading with some amusement this morning of "improvements" in cabin heaters after 1952.
You people must be Vikings!
I am a former commercial fishermen with many winters off New England under my belt, but this airplane had brought me to my knees.
My 170 is a 1955 model with all three winter baffles installed. Flight is tolerable from 20 to 30 degrees Fahrenheit, but from the teens on down, forget it.
I flew yesterday in the single numbers (Fahrenheit) and my feet, which almost never get cold, were like blocks of ice.
I have read where some of you have engineered modifications in the name of heat. That is not an option for me; as we say in Maine, I couldn't put a button on an outhouse door.
I used to instruct in a 150 that was so drafty we would stuff a jacket (yes!) around one door on winter cross countries, but other than that we thought nothing of it.
This airplane isn't drafty, it's just cold.
What are my options, other than a magnetic heading of 225 and three fuel stops?
You people must be Vikings!
I am a former commercial fishermen with many winters off New England under my belt, but this airplane had brought me to my knees.
My 170 is a 1955 model with all three winter baffles installed. Flight is tolerable from 20 to 30 degrees Fahrenheit, but from the teens on down, forget it.
I flew yesterday in the single numbers (Fahrenheit) and my feet, which almost never get cold, were like blocks of ice.
I have read where some of you have engineered modifications in the name of heat. That is not an option for me; as we say in Maine, I couldn't put a button on an outhouse door.
I used to instruct in a 150 that was so drafty we would stuff a jacket (yes!) around one door on winter cross countries, but other than that we thought nothing of it.
This airplane isn't drafty, it's just cold.
What are my options, other than a magnetic heading of 225 and three fuel stops?
Jerry Fraser
1955 C170B
Wells, Maine
1955 C170B
Wells, Maine
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Re: Wanted: Heat!
They are all drafty.
Do you have a wool headliner? Lots of cold air comes in from the tail boom. I have a vinyl headliner and I tape up the speaker holes cuz it's like a waterfall of cold air right down on my shoulder. I plan to make bulkheads to better seal that off.
Check your heat muff for obstructions. Maybe a birds nest is blocking the inlet?
Also, your heat valve may be worn out (the flapper valve has baffle material to seal it. If it's old worn and cracked, you could have lots of cold air premixing with the warm air before it hits your toes.
My heat duct inside the plane (1952) gets to about 220 degrees. I'd imagine yours should be the same so check it in flight with a fancy laser thermometer.
Take a strip of paper and close it in your doors to check how well they seal. Check all around. It the paper can call out or has no friction, you're getting cold air there. Don't over do the seals tho as it puts a big load on some very expensive hinges. I used AviationDepot memory foam insulation strips and trimmed it with scissors to the right height for each section of the door.
If all else fails, heated socks and a heated seat cover will work wonders.

Check your heat muff for obstructions. Maybe a birds nest is blocking the inlet?
Also, your heat valve may be worn out (the flapper valve has baffle material to seal it. If it's old worn and cracked, you could have lots of cold air premixing with the warm air before it hits your toes.
My heat duct inside the plane (1952) gets to about 220 degrees. I'd imagine yours should be the same so check it in flight with a fancy laser thermometer.
Take a strip of paper and close it in your doors to check how well they seal. Check all around. It the paper can call out or has no friction, you're getting cold air there. Don't over do the seals tho as it puts a big load on some very expensive hinges. I used AviationDepot memory foam insulation strips and trimmed it with scissors to the right height for each section of the door.
If all else fails, heated socks and a heated seat cover will work wonders.

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Re: Wanted: Heat!
One thing's for sure: There is no way the air coming out of that duct is 120, let alone 220. So we will start there.
Thanks
Thanks
Jerry Fraser
1955 C170B
Wells, Maine
1955 C170B
Wells, Maine
- GAHorn
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Re: Wanted: Heat!
Your '55 model should have plenty of heat, IMO.
I did install a bulkhead above/aft of my rear bagg shelf to stop the airflow from the fuselage migrating into the cabin (which also reduces exhaust and noise ingress.)
Good cabin door seals are a MUST. Also, inspect/repair the entire cabin heater system, from mufflers to heat-valve, to distribution ducts (which have many times been found full of mice-nests in some airplanes.)
I did install a bulkhead above/aft of my rear bagg shelf to stop the airflow from the fuselage migrating into the cabin (which also reduces exhaust and noise ingress.)
Good cabin door seals are a MUST. Also, inspect/repair the entire cabin heater system, from mufflers to heat-valve, to distribution ducts (which have many times been found full of mice-nests in some airplanes.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

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Re: Wanted: Heat!
It sounds between you and David as though I am not getting my full measure of heat via the ducting. Which I don't doubt, I used to fly around in a '57 172 and cabin heat was not an issue.
Assuming there is no nest how should the heater valve assembly look when heat is full on (maximum heated air). I wonder if I am getting the full throw.
Assuming there is no nest how should the heater valve assembly look when heat is full on (maximum heated air). I wonder if I am getting the full throw.
Jerry Fraser
1955 C170B
Wells, Maine
1955 C170B
Wells, Maine
- canav8
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Re: Wanted: Heat!
Check for mouse nest in the ducts.N3548C wrote:It sounds between you and David as though I am not getting my full measure of heat via the ducting. Which I don't doubt, I used to fly around in a '57 172 and cabin heat was not an issue.
Assuming there is no nest how should the heater valve assembly look when heat is full on (maximum heated air). I wonder if I am getting the full throw.
52' C-170B N2713D Ser #25255
Doug
Doug
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Re: Wanted: Heat!
Make sure those winter intake covers are not blocking off the incoming air flow to the muffler. I personally do not use intake air restrictor plates because they can cause problems such as you are seeing. It sounds to me like there is not enough supply air for some reason which in turn will not move the heat into the cabin. Something is restricting air flow somewhere or there is a major leak between the intake scoop and firewall valve. Even if the firewall valve flapper seals are completely gone, you should be getting more heat than you are.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
2023 Best Original 170A at Sault Ste. Marie
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
2023 Best Original 170A at Sault Ste. Marie
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
- 54170b
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Re: Wanted: Heat!
I really like how this heat tube turned out on ____'s 52'
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Re: Wanted: Heat!
It's nice, but I might as well attempt to build the space station as re-create that installation.54170b wrote:I really like how this heat tube turned out on ____'s 52'
Jerry Fraser
1955 C170B
Wells, Maine
1955 C170B
Wells, Maine
- n3833v
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Re: Wanted: Heat!
I found on mine between the firewall and the next bulkhead a short section piece of ducting hose torn. After I replaced it was a different heater.
John
John
John Hess
Past President 2018-2021
President 2016-2018, TIC170A
Vice President 2014-2016, TIC170A
Director 2005-2014, TIC170A
N3833V Flying for Fun
'67 XLH 900 Harley Sportster
EAA Chapter 390 Pres since 2006
K3KNT
Past President 2018-2021
President 2016-2018, TIC170A
Vice President 2014-2016, TIC170A
Director 2005-2014, TIC170A
N3833V Flying for Fun
'67 XLH 900 Harley Sportster
EAA Chapter 390 Pres since 2006
K3KNT
- 54170b
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Re: Wanted: Heat!
My heat box was damage on my 54' so I installed this one and it took me 2 hours to "re create" this installation. I can send you my measurements if you likeN3548C wrote:It's nice, but I might as well attempt to build the space station as re-create that installation.54170b wrote:I really like how this heat tube turned out on ____'s 52'
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Re: Wanted: Heat! UPDATE
I haven't been to the airport this work week but the mechanic I use looked it over and said via email the cabin air valve wasn't open all the way. He rectified things and said "You should be all set."
I do not know whether he was speaking with respect to the cabin controls (which I believed to be set to max) or the actual valve, but I will look it over this weekend and if possible, fly it and report back.
I do not know whether he was speaking with respect to the cabin controls (which I believed to be set to max) or the actual valve, but I will look it over this weekend and if possible, fly it and report back.
Jerry Fraser
1955 C170B
Wells, Maine
1955 C170B
Wells, Maine
- cessna170bdriver
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Re: Wanted: Heat! UPDATE
It may sound a bit counterintuitive at first if you aren't familiar with the system, but for maximum heat in a late B-model, the "fresh air" must be full ON (control pushed all the way IN). This valve is downstream of the heat diverter valve, and it's purpose is to isolate the firewall forward from the cabin in the event of smoke/fire in the engine compartment. When this valve is closed (knob fully out) there will be no air, heated, fresh, or otherwise, getting from the engine compartment into the cabin.N3548C wrote:I haven't been to the airport this work week but the mechanic I use looked it over and said via email the cabin air valve wasn't open all the way. He rectified things and said "You should be all set."
I do not know whether he was speaking with respect to the cabin controls (which I believed to be set to max) or the actual valve, but I will look it over this weekend and if possible, fly it and report back.
I never made a habit of it, but at least once I took off in single digit (F) weather and climbed to -20 OAT and my stock '55 heater kept the cabin warm enough to shed gloves and hat (and at that point I'd lived my entire life south of the Ohio River, so I'm definitely NOT a Viking!

Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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Re: Wanted: Heat!
That's where the controls are set. Flew it yesterday, quite comfortable but the OAT was in the 40s. So I'm skeptical it will be comfortable when it gets cold... so something may be going on... or not. It's going to colder soon, though, so we'll see.cessna170bdriver wrote:
It may sound a bit counterintuitive at first if you aren't familiar with the system, but for maximum heat in a late B-model, the "fresh air" must be full ON (control pushed all the way IN). This valve is downstream of the heat diverter valve, and it's purpose is to isolate the firewall forward from the cabin in the event of smoke/fire in the engine compartment. When this valve is closed (knob fully out) there will be no air, heated, fresh, or otherwise, getting from the engine compartment into the cabin.
I never made a habit of it, but at least once I took off in single digit (F) weather and climbed to -20 OAT and my stock '55 heater kept the cabin warm enough to shed gloves and hat (and at that point I'd lived my entire life south of the Ohio River, so I'm definitely NOT a Viking!)
Jerry Fraser
1955 C170B
Wells, Maine
1955 C170B
Wells, Maine
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