Operating instructions

Heatmax Furnace Installation and Operation Manual
59
9.2 Manual or thermostat control
From factory, the opening and closing of the air inlet damper is manually activated by the
means of a switch located at the rear of the furnace. The switch has two positions; opened
and closed.
For added comfort, the installation of an optional wall thermostat is recommended since it
will open the air inlet damper when the room temperature is below the set point of the
thermostat and will close the air inlet damper as the desired temperature is reached (see
Appendix 1: Optional Thermostat Installation).
If the heat sensors detect any overheating in the air jacket of the furnace, the air inlet
damper will close automatically regardless of the type of control used.
9.3 Fan control
The fan is activated when the air jacket temperature of the furnace reaches 140 °F and
stops when it drops below 120 °F. If the air jacket temperature exceeds 160 °F, the air inlet
damper closes and the fan will continues to blow until temperature returns below 120 °F at
which point the air inlet control will open again.
To optimize the heat distribution efficiency of the furnace, the blower of the HEATMAX was
set at the factory on speed 2 (medium-low). If needed, it is possible to change the fan
speed by moving the black wire coming from the control box to the desired speed (see
electrical diagram). Make sure the new setting complies with the recommendations of the
National Association of Hot Air Heating and Air Conditioning while respecting the
recommended static pressure.