Operating instructions

Heatmax Furnace Installation and Operation Manual
24
4.4.2 Combustion efficiency
Even the best-built wood furnaces should be well used to obtain maximum efficiency. A
furnace that overheats will not transfer more heat to the inside, as this will increase the
heat loss through the chimney. Using a thermometer will help you control the temperature
of your furnace and achieve optimum performance when controlled manually.
4.4.3 Protect your furnace
It is impossible to determine the temperature of the chimney flue and the furnace by a
simple look at the flames. A thermometer tells you when the fire is too hot, which helps you
avoid damages to the components of the combustion chamber therefore prolong its
service life.
4.4.4 Control of the air inlet damper
Always turn the furnace on with the air inlet damper open. Once the temperature of the
wood, the combustion chamber and the chimney is stable, close the air inlet damper to
obtain a more efficient combustion.
To control the air inlet damper, use the switch on the side of the control box located at the
back of the furnace.
Reducing the combustion air will do two things. First, the combustion rate will decrease,
which will spread the thermal energy of the fuel over a longer period of time. In addition,
the velocity of the exhaust gas decreases, which allows better heat transfer in the heat
exchanger and chimney.
The closure of the main air intake reduces the intensity of the flames which indicates the
achievement of optimum performance. If the flames diminish in intensity at a point where it
almost disappears, it is an indication that the air inlet damper was closed too soon or the
firewood used is dry enough. If the wood is dry enough and the air control is closed when
the unit is at a stable temperature, the flames will decrease but remain strong and stable to
provide efficient heating.
For ease of use, an optional thermostat can be easily added to the furnace which would
automatically control the air inlet damper to keep the temperature stable. For complete
information about this option, refer to Appendix 1: Optional thermostat installation.
4.5 Ash drawer
Your furnace is equipped with an ash drawer to collect ashes produced by the combustion
of wood. The ash drawer is provided with two (2) wing nuts to hold the door in a close
position. Operating the furnace with the ash drawer open may seriously damage the
furnace. The drawer must be emptied regularly.
WARNING: IT IS IMPORTANT THAT THE FIRING DOOR, THE ASH DRAWER AND
THE ASHPLUG BE KEPT CLOSED WHILE THE APPLIANCE IS IN USE. MAINTAIN
ALL GASKETS, IF ANY, IN GOOD CONDITION; IN CASE OF DETERIORATION,
CONTACT YOUR DEALER FOR A GENUINE REPLACEMENT GASKET.