Matt Hennek

While I've seen some very ingenious hot water heaters heated by rocket mass stoves (i.e. Nick Ritar's), I haven't seen many people use water as a heat mass.  More people seem to tend to gravitate towards cobb as a heat mass.  I think waters high specific heat and ability to efficiently conduct heat would make it an excellent  heat mass for a rmh, but I'd be a little concerned about it's weight.

Since I'm quite a noob when it comes to RMH's, I have a few questions:

1. What's the specific heat of cobb?  Water has a very high specific heat of 4.18 J/g.  I know this will greatly depend on the clay source and ratio of straw to clay, but does anyone know a general estimate?

2. What's the density (gram per cu cm) of cobb?  I've heard Mr. Wheaton mention a few places that it's quite heavy. 


Thanks!

Hi All,

New to the forum.  Looks like a great place.

One question that has been bugging me regarding rocket mass stoves, or any fireplace for that matter is the effect of air intake cooling your home.

When you're operating any fireplace (rocket stove or not), if your air intake is within your home you are effectively creating a vacuum inside your house, pulling cold air into your house. 

Why not put your feed box on the outside of your home and pipe the hot exhaust into your house?  This way the air going into and out of the stove is from the outside and you don't pull cold air into your house. 

You could keep the feed box inside your house for easy access so long as their's a door flap over it and an air intake pipe leading to the outside.

Thanks.

Matt