The furnace serviceman showed up at 8:30 AM as promised and quickly diagnosed the problem as fatal...the furnace was 23 years old. The inducer was bad and the overall condition did not warrant replacement. The serviceman recommended a new furnace. I had a Bryant and they replaced with a Bryant. The efficiency rating increased to 95% from 92.5%. However, this was a major purchase and I didn't feel like enough time was spent reviewing the pluses / minuses of the unit or the brand. The two-stage burner seems to have helped heat distribution throughout the house, however the noise level when the blower is running is higher than the old unit. We could not hear the old unit running whereas the new unit can be clearly heard. The new furnace installation man arrived on time and within 4 hours had the new unit temporarily installed and heating the house....good because we had been without heat for about 22 hours. 48 hours later they returned to complete a professional looking installation including a new humidifier, air filter and thermostat. Overall, very pleased.