Routing Erbespacher (or similar) heater exhaust into engine exhaust?

[alaska7]

I'm looking to fit a heater to my Endurance 35 and am considering an Erberspacher style unit. The engine and fuel tank in the Endurance 35 are in the middle of the boat under the main cabin sole and there is loads of space in the engine bay to mount a heater.. I am wondering if anyone has any advice on whether it is possible to pipe the heater exhaust into the engine exhaust system at all? Is this a crazy idea?
Failing that I have heard that the Erberspacher units waste quite a lot of heat in the form of hot exhaust and was wondering if by running the exhaust from the middle of the boat under the sole all the way back to the transom might be a way of utilising some of this heat for.. well heating Would this be unsafe in any way.. obviously exhaust gasses are dangerous but it would be fully sealed. - could have CO detectors mounted along the way too..
Any help from the wise and learned on here always appreciated
Cheers

 

[sailorman]

most heaters are limited in the exhaust length they will tolerate. suggest you have a search of manufacturers requirments

 

[alaska7]

most heaters are limited in the exhaust length they will tolerate. suggest you have a search of manufacturers requirments

yes this might be a problem.
Maybe if after the initial exhaust at the original diameter the continuing ducting became significantly larger that would get around this?

 

[pvb]

I am wondering if anyone has any advice on whether it is possible to pipe the heater exhaust into the engine exhaust system at all? Is this a crazy idea?

Yes, I think it is crazy. The Eberspacher exhaust should go directly to the outside air. The exhaust gas is hot and could damage the engine exhaust pipe. Then there's the possibility of engine cooling water getting in to the Eberspacher exhaust.

 

[rotrax]

Yes, I think it is crazy. The Eberspacher exhaust should go directly to the outside air. The exhaust gas is hot and could damage the engine exhaust pipe. Then there's the possibility of engine cooling water getting in to the Eberspacher exhaust.

Dead on! The diesel heaters-of whatever make or type- will produce hot gas that would damage the rubber elements of your boats exhaust unless water was flowing in it as it does when the engine is operating.

Unless you have an all metal exhaust its a non starter.

 

[pcatterall]

Cant see a sensible way to pipe into engine exhaust.
Always possible to install some sections of exhaust so they don't touch or get within an inch or so of anything inflammable so maybe under a floor but NOT in a locker where ( for sur)someone will shove something inflammable onto it!! Consider also condensation in a long pipe can be an issue.

 

[pvb]

...but NOT in a locker where ( for sur)someone will shove something inflammable onto it!!

Or, worse still, something which might catch fire!

 

[NormanS]

Or, worse still, something which might catch fire!

My Eber exhaust goes partly in a locker, but it is well, and easily protected by a fixed guard made from s/s weldmesh.
However, for all sorts of reasons, I wouldn't contemplate connecting into the engine exhaust. Back pressure, overheating rubber components etc.

 

[Chris_Robb]

Remember that the intake of air to the heater unless ducted to another compartment, will come from the engine room with perhaps some residual oil and diesel smells.

Its good practice anyway to have the air intake ducted into another compartment, so guarding against a leak of C Monoxide from the unit's exhaust. I note that my professionally installed one does not follow this advice!!!!

 

[NUTMEG]

Recently fitted a recon Webasto and remember the makers installation instructions expressly forbid plumbing the exhaust into the engine system. I was also advised to add a heating air intake pipe to draw air from the cockpit and not from the locker the heater lives in. So I concur with all the advise above!

 

[salar]

Recently fitted a recon Webasto and remember the makers installation instructions expressly forbid plumbing the exhaust into the engine system. I was also advised to add a heating air intake pipe to draw air from the cockpit and not from the locker the heater lives in. So I concur with all the advise above!

Heating air intake needs to be ducted from outside otherwise you increase the condensation inside. Also combustion air needs to be drawn from outside to remover the risk of using up the oxygen in an sealed cabin! Webasto exhausts get very hot, even wrapped in the fibreglass sleeve supplied so it needs very careful routing and preferably short - straight out of the side.

 

[pvb]

Heating air intake needs to be ducted from outside otherwise you increase the condensation inside.

I agree with you - but you'll find there are many here who will disagree, preferring to recirculate cabin air for faster heat-up.

 

[David2452]

Surely this is a wind up?

 

[pvb]

Surely this is a wind up?

Perhaps!

 

[Jabs]

Surely this is a wind up?

I sincerely hope so!

Tony