why aren't oil coolers use for cabin heat

[jhausch]

I guess the subject says it all. Would this be safer than exhaust shrouds?

 

[Tom-D]

I guess the subject says it all. Would this be safer than exhaust shrouds?

Because on cold days it never gets warm enough, and on hot days it works too well.

 

[brien23]

When its 100 outside they work hard when its 20 they don't. When you would like the heat and it's cold you would not get very much.

 

[Velocity173]

Some are. Most Velocitys use an oil cooler in the nose. Not as efficient as an exhaust shroud though. Once you get into the 20s it doesn't keep the cabin very warm. Also I know of at least one forced landing from an oil line breaking. It is nice not having to worry about Carbon Monoxide poisoning.

 

[jhausch]

Interesting. thank you all for the fast replies.

in the examples where people are talking about it not getting hot enough on cold days, is it good practice to partially shroud your oil cooler when its really cold?

 

[Velocity173]

Interesting. thank you all for the fast replies.

in the examples where people are talking about it not getting hot enough on cold days, is it good practice to partially shroud your oil cooler when its really cold?

Mine is fully exposed through a NACA vent in the left side of the nose. I guess if I got a partial restrictor that might give me some more heat in the winter. Usually it's only a problem when it's overcast and extremely cold. If its sunny out it's quite comfortable in the winter months.

 

[murphey]

Interesting. thank you all for the fast replies.

in the examples where people are talking about it not getting hot enough on cold days, is it good practice to partially shroud your oil cooler when its really cold?

Depends on the aircraft. For example, most cherokees (PA28 in all its forms) are placarded for an oil cooler cover when ambient temps are 50F and below. Best source is the POH/AFM.

 

[Dan Thomas]

For the typical aircraft piston engine, the total heat energy released by the combustion of the fuel is divided up about like so:

25% to oil and cylinder air cooling, most of that from the cylinders/heads. Not much from the oil cooler, and many smaller engines don't even bother with oil coolers.

25% to useful power to the prop and accessories.

50% out the exhaust.

If we want decent cabin heat, we use the exhaust system. That's where the real heat is found.

Dan

 

[LDJones]

I think the difference is a few hundred degrees sometimes vs. 1300-1500 degrees all the time.

 

[Ted]

I think the difference is a few hundred degrees sometimes vs. 1300-1500 degrees all the time.

Well, more like 700-800 at idle.

Of course, our cars run the heater with about 200 degree coolant, and it works well. But oil works best a bit colder, and the heater doesn't work great that way.

 

[LDJones]

Well, more like 700-800 at idle.

But we are freezing while taxiing and idling!!

 

[Silvaire]

The bottom line is that there are over seven billion people on this planet. Seven BILLION. So if using the oil cooler for cabin heat would work then we'd already be doing that. If you're gonna come up with a great idea to solve an age old problem it's gonna have to be something extraordinary. You've got a lot of competition out there.

 

[SoloEqs]

A leaking oil line or connection could fill the cabin with an explosive vapor, while at the same time making it impossible to see or breathe.

I can't think of a better reason to not use the oil cooler for cabin heat.

 

[Henning]

For the typical aircraft piston engine, the total heat energy released by the combustion of the fuel is divided up about like so:

25% to oil and cylinder air cooling, most of that from the cylinders/heads. Not much from the oil cooler, and many smaller engines don't even bother with oil coolers.

25% to useful power to the prop and accessories.

50% out the exhaust.

If we want decent cabin heat, we use the exhaust system. That's where the real heat is found.

Dan

Yep, I'd like to water jacket my exhaust and run it to a heater core in the cabin rather than have a combustion heater.