dougrainer wrote:
If you have a blockage, the furnace burner would short cycle and you would hear it cut on and off. Doug
Yes mine did this. Fan would run continuous but if you really paid attention the burner would cycle on and off every 30 to 90 seconds.
My ducting had a few issues. First the short section from furnace to main line protruded 40% into the main line and blocked airflow. Secondly the short section collapsed during installation and was restricted. Flashlight and mirror found these issues.
Used a hole saw to open the metal protruding into the main line. Used some square aluminum that I perforated for air flow as a scaffold to prop open the collapsed section.
Helped some but the real solution was to pop out two of those knock-outs and add two more 4" ducts direct to the living area. Now I get tons of massive heat compared to before. Burner runs continuous until heat gets to the thermostat. Far less furnace fan run time.
