Dust that accumulates inside the unit of a propane heater can prevent it from lighting and ultimately adding warmth to a chilly room in a house or other enclosed area. For safety reasons, a propane heater's oxygen sensors keep the heaters from lighting if dust is present. Giving the propane heater a thorough cleaning can help avoid a difficult lighting process and also help keep the heater lit once ignited.

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A flame on a propane heater won't ignite if dust has gathered around its sensors.

Step 1

Make sure the propane heater is turned off. Vacuum as much dust and debris as you can from the outside of the heater, and vacuum inside the vent holes and grids on the heater.

Step 2

Use a small paint brush for brushing dust away in tight areas. Gently move the brush over the igniter and the flame areas on the heater.

Step 3

Remove the screws that hold the heater's cover panel, remove it and wipe the inside of it with warm water. Dry the newly washed area and set it aside.

Step 4

Gently vacuum the parts inside the propane heater, and use the paintbrush to brush off dust from around the oxygen sensor located near the gas line tubing.

Step 5

Put the panel cover back in place and tighten the screws. Light the heater as instructed in the operating manual.