My 20 year old furnace died in the middle of a cold spell. I called about 8:00 am on a Tuesday, and a repairman was at my door by about 12:30. Unfortunately, the old beast was beyond repair and tagged as unsafe. A day and a half later (Thursday), installers showed up, took the old furnace away, installed a new one, and everything is working fine. I was very pleased with the speedy service, especially considering the pressure on an HVAC company during a cold spell. FYI, I opted for the priciest unit, thinking it will ultimately be the best value. BTY, they did me a similar solid several years ago when my air conditioner died during a heat wave.