I called around to a few places and Knight said the right words with the lowest call out fee. The tech was very experienced and diagnosed the problem in less than 5 minutes. He then immediately sourced the replacement part (super lucky these days), went and picked it up, and installed it all on the same appointment. Even though it was a pricey part I am happy with the service. The only warning is to get confirmation of the full cost before having Knight come out. While they had the lowest call out fee, there seems to be an additional fee if you want the tech to actually look at your furnace (diagnosis fee). That was not mentioned when I called to set up the appointment.