kees vd kooi

thomas rubino wrote:I prefer using a larger brick; the heat-up time inside the riser is reasonably quick.
Split bricks crack  much more easily than a full-size brick.

Perhaps, you could use a metal exhaust pipe externally, making a bypass installation easy.
Once in place, you could brick false walls to cover over the unsightly pipe.

Okay thanks. Then I wil use the full size bricks.

Yes that's also possible, a lot of thinking I have to do now. :)

Het Peter thankyou for the answers.
It's easier for me if we talk on th dutch ecologieforum, so I prefer that.

I have also a little question about the riser firebrick thickness.

Would you recommend a firebrick of 2.17 inch or a 1.18 inch? I think the thinner brick is better to heating up the riser more quickly, but the thicker
one has a better longevity?

The Sidewinder sketchup version of Peter shows a thick brick, but multiple youtube build video's shows thinner bricks. So I'm confused.

Yes that's correct, bricked inside the bell.

It should be possible; on a dutch forum was a guy that made from steel a bypass in the inner chimney, but it was a bit complicated so I prefer to avoid it.

Yes your right, a external flue pipe is much easier but the wife don't like the view ;(

Oke thankyou for your opinion. I'm a little bit confused now because I thought I had read on a dutch forum a post from Peter vd Berg who said if you don't exceed the preferred ISA of 55.97 Sq Ft., it would be possible without a bypass. But maybe this is only meant for a chimney outside the Bell.

Hello I'm Kees from Holland and I'm planning to make a Batch rocket mass heater.

One thing isn't clear for me despite searching a lot on this forum and watching Ytube vids. I hope to get answers here and would be very grateful.

I would build a RMH  based on a 177cm2 riser channel, it would be a sidewinder. (I use the exact measurements who Peter Berg recommended)
All the necessary information I have are from batchrocket.eu and has been applied.
So my ISA should be 5.3 m2, which i calculated exactly like this (innerside of bell is H: 173cm/D: 54cm / W: 90cm. And  minus the fire chamber hole on the front side ofcourse.

My half brick Bell wall under riser level are hard brick stone (18x9x4cm), above that I use Fire bricks up to 1200 degrees (a double layer with superwool between it as recommended)

Now I would build a bricked internal chimney for the exit flue. First the hard stone brick and above riser level the Firebrick to above ceiling of the Bell.

The main question is: do I need to make a bypass in the bricked chimney? Otherwise I have maybe problems with starting up the heater and the smoke coming back in the living room because the internal chimney is too cold.
I prefer to do not because I think i'ts more sensitive for damage.

Thanks for answerring me.