Does the fan start?
If your furnace does not start, you can begin your diagnosis at the thermostat. Ensure that the
thermostat is on heat and the setpoint is above the actual room temperature. Next, you can turn the fan
from auto to on.
If the fan does no come on, you should check the breaker or fuse for the furnace. If the breaker is
tripped or the fuse is blown, you should check the furnace wiring for signs of damage and then reset the
If the breaker was not tripped, the problem could be the primary control, the thermostat, blower
motor, fan timer control, or it's run capacitor. After the blower
is running, the fan can be placed back in the automatic mode at the thermostat.
If the blower runs but the burner does not come on, then you should check the reset button on the
primary control. If the red reset button is sticking up, push it down and release it.