Diesel heater exhaust penetration through foam core.

[simple]

I'm curious what people have done when running a diesel heater exhaust through walls / floors with a foam core.

Foamular 250 NGX has a max temp of 165F and diesel heater exhaust pipes can hit 400-600F.

On my spacekap build I used a double wall boat through hull fitting. The hole through the fiberglass is larger than the body of the fitting. The whole thing mounts and seals to the outside of the glass with a large flange. This has worked well for that application. I also imagine the glass has a higher heat rating than a foam panel.

A thought I had for the foam wall is to cut a larger diameter hole through the foam 2-3" and insert a sleeve into it which creates clearance around the exhaust pipe running through the center. It could be an uninsulated air gap or I could fill the void with something like exhaust wrap.

 

[simple]

Maybe pack the void with this stuff.
Ceramic fiber insulation good to 2400F and not very expensive.

Amazon insulation link

 

[Joe917]

Keep the heater outside the heated envelope, run the coolant lines through the foam.

 

[simple]

Keep the heater outside the heated envelope, run the coolant lines through the foam.

That makes sense for hydronic. For this I'm doing a hot air application.

 

[JaSAn]

Wall thimble (double wall pipe with flange on both ends); like what is used to route chimney pipe through wall or roof.

 

[andy_b]

Not sure what heater you’re using, but Total Composites sells this flange: https://expeditionupfitter.com/collections/diesel-heater/products/mounting-flange-for-air-heater

I’m using it in my TC camper without any issues.

 

[simple]

Not sure what heater you’re using, but Total Composites sells this flange: https://expeditionupfitter.com/collections/diesel-heater/products/mounting-flange-for-air-heater

I’m using it in my TC camper without any issues.

It's hard to tell from the pictures. Can you fasten the heater to the flange and then fasten the flange to its mating surface?

 

[andy_b]

It's hard to tell from the pictures. Can you fasten the heater to the flange and then fasten the flange to its mating surface?

Exactly. I think they import it from Germany. It is a great solution.

 

[Alloy]

It's called a concentric vent.

Filling the gap with mineral wool (Roxul) is an option.

 

[Alloy]

Keep the heater outside the heated envelope, run the coolant lines through the foam.

If it's starting 2-3 time an hour then having it out in the cold will increase the build up of soot.

 

[Victorian]

Exactly. I think they import it from Germany. It is a great solution.

You are correct. I have been using them for several years on all of my personal builds. They are nicely made and seal/protect the floor and heater from the heat and elements. Selling like hot cakes lately. Out of stock at the moment with new inventory arriving within the next two weeks.