I've been a homeowner for about 2 years now, and until recently never changed the air filter. Finally, I changed filters to the Filtrete Dust Reduction 300 filter. However, within a couple days, I noticed that my heater started having periods where the pilot would kick off, and the furnace would only blow cold air. After frequently experiencing this, I put the old 2 year filter back in, which by the way is a Filtrete Maximum Allergen, and never had a problem.
Based on this, I decided to go with a higher quality filter, and opted for the Filtrete Ultra Allergen. Again, I started experiencing the same thing where the furnace would stop producing heat and instead only blowing cold air. Again, I put my old Maximum Allergen filter back in and have yet to have a problem.
My question is is this plausible, or is it merely a coincidence that the filter is causing this? I've read in my instruction manual to replace my filter with a "high-velocity" filter. Is my Maximum Allergen filter "high-velocity" while the other two weren't? Is there something else with the filter that could be causing my furnace to shut off?