- 1). Check that the supply and return registers are free of obstructions if the blower continuously runs and there is insufficient heat. Clean or replace filters as necessary. Remove the blower door and flex the filter and lift it clear from the the bracket. Vacuum the filter until it is clean, then replace. Replace the blower door.
- 2). Check the home electrical panel to see if any fuses are blown. Always replace fuses with another of the same amps. See if any breakers have tripped. Reset as necessary.
- 3). Check that the thermostat is on and set to the desired temperature if there is no heat and the blower does not work. Try turning the system on and off in the space of 30 seconds. Make sure that the blower door is not slightly open.
- 4). Check the furnace condensate drain if the blower is running but there is no heat. The drain may be clogged. Remove the clamps to the condensate trap and drain the trap outlet. Allow the blockage to flush out and reinstall the clamps.
- 5). Turn off the gas and electrical power. Check to see that the flue system is free of corrosion and obstructions. Make sure that the vent screen at the end of the flue is clean and free of obstructions.
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