SAFE water heating system for wood stoves

Safe Water Heating with Wood Stoves • Hot-Jacket


It has never been safe to place water coils inside fire boxes when heat source cannot be cut off in an instant. Pressure/temperature valves are not meant for control purposes, but for disaster mitigation in case other systems fail. Water coils in contact with high temperatures, such as found inside wood stoves and on wood stove surfaces, can develop very high internal pressures if piping is closed and if system relies on relief valves. There is no way to turn off the heat! This makes these systems unsafe.


Heat-Booster Energy Systems has developed a SAFE water heating system for wood stoves. System is available as a retrofit kit that is adjustable to fit most common stove sizes. Double or triple coil arrangements are optional.
OEM stoves will be incorporating the systems in new stoves. Major stove manufacturers will offer the water heating option with some of their most efficient stoves.

The kits consist of sheet metal covers that can be installed without any tools. Covers form a canopy that collects hot air from sides, top and back of stove. The hot air is drawn, using a blower, across a finned coil located at back of stove. Blower also helps with air circulation in room. Water from a hot water tank and/or hydronic heating system is circulated through the finned copper coil. A temperature and/or pressure switch can be used for control purposes. Switches turns off blower and circulating pump when temperature has reached a desired maximum. Hot air does not contact coil when blower is off. Air temperature cannot get hot enough to create high pressures inside coil. Maximum pressure is same as in typical domestic water systems.

Heat transfer to water can be maximized by installing a HB2 heat reclaimer with a water heating coil. The two coils can then be operated in series, or as independent systems. This provides some very interesting opportunities.

Flue Gas Heat Recovery - HB2

Overall efficiency of most wood stoves is in the 50% range, where efficiency is the percentage of energy in wood fuel that is transferred to media (air or water) to be heated. Stove manufacturers usually advertise combustion efficiency as determined during EPA emission certification testing. Overall efficiency is defined as combustion efficiency multiplied by thermal efficiency. Thermal efficiency is defined as the percentage of energy available that is transferred to media to be heated. For example: 70% combustion efficiency times 70% thermal efficiency becomes 49% overall efficiency. This is the reason the HB2 heat reclaimer has been developed.


Eliminate poor draft with a venturi type draft inducer. Drops into top of chimney. Runs on 110 V AC. No moving parts in flue gases.

Cost Efficient Solar Thermal Energy

Wood stoves may produce too much heat in spring and fall. This makes water heating "uncomfortable" during these times and during the summer months. The answer to this problem is efficient, low cost solar heat.
Heat-Booster Energy Systems have developed a highly efficient and low cost solar thermal panel that also functions as roofs, walls and fences. It can of course be installed on free standing racks. There are no liquids in the panels.
Hot air from the panels is blown into a room when air temperature in room is lower than in collector, or the hot air is drawn across a finned coil when coil temperature is lower than collector air temperature.
Warm attic air can also be used to pre-heat water. This is very cost efficient.
HBES has also developed a hybrid solar panel that produces hot air and electricity. This is a game changer in that installed cost of system is very low.