Wood Stove with Heat Exchanger

Introduction

This is a hydronic space heating stove where the heat exchanger is located in an openable fire chamber. Identical design may be used to run the Hadden Modern Steam Engine if at full blast. The intent is space heating of 2000 square feet, including hydronic radiators for remote rooms.

Heat Exchanger

• 160 feet
• Pancake coil configuration, 4" inner hole, 22" OD of pancake
• 1/2" schedule 40 black pipe
• $2/foot materials cost for coil
• See YouTube for Coil Fabrication

Stove

(edit)

Heat Calculations

See https://docs.google.com/spreadsheet/ccc?key=0Ani3apcWYfzDdGhGblBJczdZTVBHVi1GdzduVkotQlE#gid=1

If square footage of hablab is 3000 and average height is 8 feet, the cubic volume is 24,000 cubic feet.

BTU Requirement Formula = cubic footage * .133 * fahrenheit degree change = ~200,000 btu

Peer Review

• Ben Hansen - Put a Catalytic Converter under the coil, that will keep it from being a drippy tar magnet, and you can focus the heat on to the coil pack. A big burn chamber, line it with firebrick, secondary coil and heat exchange area works well. Model to look at is a simple barrel stove double barrel kit.
• Aaron Makaruk -

• The surface of the barrel can be used for cooking.
• The water pipes are easier to channel throughout the HabLab than a Rocket Mass Stove exhaust pipe.
• Experiment option: pancake coil on top of the barrel.
• Experiment option: vertical coil along the vertical exhaust shaft of the rocket mass stove.

• Ben Hansen - catalytic converters in Mother Earth News - also source - Bought stuff from these guys. The "men" link is old, and reference only. Lots of good stuff out there now.
• Darren Hill - I have built a top lit side draft gasifying stove based upon GTZ7 with great help from the designer via the stoves list it is small and appears to require fuel to be processed accordingly (read small, still under testing). I think a larger version could work well with bigger logs. A restricted flue outlet, with alternative path enables heat exchanger to be brought into play aromatically as the burn establishes and volume of output gases exceeds that which the restricted outlet can flow. A suitably sized flue will provide the required draft to provide good combustion. I think I'm right in saying that the more complete combustion achieved in a gasifier stove should drastically reduce any tar deposits on the heat exchanger. --DOHill 14:24, 23 August 2012 (CEST)
• Parker Bonnell - Link to FAQ about catalytic stoves. Guide to the stoves. List of manufacturers and options.