Eric arrived on time. I had two furnaces with different issues. The vibration issue he found to be part of a bar-code label that had gotten caught in the fan rotor, throwing it off balance. He removed it, tested for vibration, then identified and described how to fix two places where items outside the furnace could vibrate against each other and amplify vibrations in the future. I have since placed insulation in both places.
The second issue was with installation of an air ranger that replaced an older conventional filter. Eric redefined the thermostat warning diagnostic to more accurately define the condition, and assured me that there is no need for a pre-filter which the diagnostic had incorrectly identified as needing replacement.
Excellent visit.
more