Hello, I am having an intermitant problem with the furnace - On two occasions in the past 3 weeks I have noticed the furnace ignite, but then not engage the blower - on both occasions it came on after I changed the thermostat setting or turned off the furnace. What should be my first step, as it seems this might be a pattern?
could be you have developed a flat spot on the motor, meaning if the furnace motor stops on it it will not want to start. but temperature can also affect it if it is just a small spot.one way to test, and be carefull about it, is when the blower does not come on when it should use a small stick (or wooden spoon) and push on the squirl fan in the direction it is supposed to spin. if it starts then it is flat spot. the other ones are the temperature sensors. if there is one for the motor then it could be faulty. there is another one that will shut down the flames if the blower does not come on.