Arrived on site for scheduled heating maintenance on x3 2016 Armstrong furnaces. Homeowner had no concerns at this time with regard to normal unit operation. 1. Visually inspected condenser coil for debris/ dirty. 2. Inspected condenser fan motor. 3. Inspected condenser fan blades. 4. Inspected/ cleaned wiring connections. 5. Tested for gas leaks 6. Tested functionality and cleaned flame sensor 7. Tested functionality and cleaned pressure switches and ports 8. Inspected / replaced return filter. 9. Inspected return plenum for debris/ dirty. 10. Inspected evaporator coil. 11. Tested functionality and visually inspected surface igniter 12. Checked blower amp draw. 13. Measured temperature differential from supply to return. 20 degrees measured. 14.Drain line tested with gallon of water for clogs and to push anything trying to solidify out Noticed a very significant amount of dust and debris in the return plenums of all 3 units. This will cause stress on the system as dust works its way
