I am looking to replace the 22 yr old gas furnace in our home and I am concerned about the bid I received. I called up the company who had installed the original unit (when the home was built), and the person who showed up walked through the house, counted the registers, and wrote up an estimate. I was at work so didn't get to talk to him. Having learned here that a heat load calculation is needed to properly size a furnace, I called an asked if he intended to do one. He left me a voicemail claiming that
1) They had done the calculation when the house was built, and nothing had changed
2) He needed to get a minimum of 100cfm at each register, and he only had one unit that could deliver that airflow; if a heat load calc indicated that a smaller unit was needed he didn't have one that could deliver 100 cfm
3) It's a 2 stage unit he proposed so there's not as much danger of oversizing as the unit will spend most of it's time at the lower setting
The price is reasonable, and we've been happy with the service this company has provided during the 4 years we've owned our home. On the one hand I feel like the company has failed to demonstrate their competence in HVAC by giving a proper, calculated estimate, on the other I feel like the furnace they propose to install is probably just fine and I don't want to get hung up on formalities. What do you all think?