rmh

I am building my first RMH. I would like to know how long can the pipe be? I would like to build a ten foot long bench, but not sure if that would create to much heat loss.

Hello Gaius,

Welcome to Permies...

Like so many trying this out for the first time, there are a lot of questions. Perhaps someone would venture to guess or get into this with the suggested sizes, yet without diagrams, and cross sectional elevation views of the plan, it really isn't something one could answer well. If one of the books and/or videos that are referenced in a "positive light" here at Permies is read and/or watched, I am sure most of your query could be more effectively answered, than what I would be guessing at.

Can you provide photos, and diagrams of your plan?

Regards,

j

I think what Jay is getting at is that it is better not to reinvent the wheel - every variation under the sun has been tried (or at least a huge number of them!) and the best of these have become the recommended designs. Rather than start with a design in mind I'd go and take a good long look through the various resources (videos, books etc...) and then look at your plan with fresh eyes.

It's not the length of the bench that matters, but the size and length of the duct running through it. An 8" diameter system can handle up to about 50', minus 5' for each 90 degree elbow.

Glenn Herbert wrote:It's not the length of the bench that matters, but the size and length of the duct running through it. An 8" diameter system can handle up to about 50', minus 5' for each 90 degree elbow.

Ernie's numbers. Of course, substracting 5 for each elbow.

http://donkey32.proboards.com/post/9290/thread