Do-It-Yourself Cleaning for Fuel Forced Hot Water Furnaces
- 1). Turn off the power on your furnace. Shut off the gas valve that is connected to it. If you know which breaker is connected to your furnace, shut that down as well before you begin to clean the unit.
- 2). Clean the exterior of your furnace, removing any dust or debris that has accumulated there. Use a handheld vacuum or a rag and warm water to clean the unit. Clean around the furnace as well.
- 3). Find where the furnace's filter is housed. Remove the filter, and clean it with the handheld vacuum, using a soft brush attachment. Clean both sides of the filter, as well as the interior of the furnace where it's kept. Put the filter back once it's clean. Clean or replace your filters three or four times per year.
- 4). Open the service hatch or drawer where the furnace blower is kept. Some models will require the use of a screwdriver to get in there. Remove the bolts that hold the blower in place, and lift it out of the unit. Clean the blower with a brush or a vacuum with a brush attachment. Clean gently, and do not disturb the wires on the device. Put the blower back in furnace when clean.
- 5). Find the furnace's pilot light. To dust it, blow through a drinking straw, hitting the dust with your breath. A dust-covered pilot light can send an erroneous message to the flame sensor.
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