Cold Air Bypass

In Igor Kuznetsov's double bell theory, based on Groume-Grjimailo's buoyancy theory, the possibility is offered to route cold gases, such as air leaks in the firebox door, directly into the chimney. They would thus bypass the heater. We would like to know how much efficiency we lose if we leave the chimney damper open, and whether we can reduce these losses by using a cold air gravity bypass.

The idea is to do a series of repeat heater runs on a 24 hour cycle, record surface temperatures, see what the effects are of leaving the damper open, and of adding a cold air bypass.

Standing in front of existing firebox, looking down. There is a grate at the rear of the firebox floor. On each side there is a
sloped piece, and in front there is a steel air diverter bar, creating a 1" air slot at the firebox floor.

The right sloped piece has been broken out. A drill hammer is used to drill two 1/2" holes about 4" through
the firebrick and precast channels, into the exit channel of the heater.

Looking from the front right corner of the firebox floor directly into the exit.
The theory is that any cold gases that leak into the heater through the firebox door, ashbox door, etc., will be heavier, and
therefore collect on the floor. The idea is to suck them through this hole directly into the chimney, rather than having them
cool the heater.

Sloped piece replaced, with relief cut into the back to clear the air hole.

Steel air bar replaced.

Test Results

Heater surface temperature curves