We ended up after a week or two of troubleshooting calling Cold Air Mechanics (Daniel Labadie) to diagnose and fix what another pretty good HVAC mechanic had problems diagnosing and fixing. After continuing problems and service calls from the other company, we went onto yelp to look for a tip-top expert in HVAC and ran across this listing on yelp. We called and got right through (if he doesn't answer the phone himself, he has a call service that will relay and he calls right back in a few minutes which can be a huge relief when you're hot under the collar due to a lack of heat!) When we talked, Daniel ran through some basics on the phone and determined that he would indeed have to come out, but we appreciated that he tried to see if it was something we could easily fix first without incurring any costs at all. After that when he arrived we were again impressed he had the patience to actually stay up in a teeny tiny cramped attic while the furnace went through multiple complete cycles to correctly diagnose the problem so he could be sure he was doing his best to find and fix the problem. He ended up fixing the problems that had stumped another company. Great diagnostic work. We would recommend to friends and family. Costs were reasonable and definitely less than the cost of replacing the parts the other company had recommended because they could not diagnose the problem. His customer service all round was outstanding and it's clear he enjoys the technical part of his job and was willing to explain it to us so we could understand it too. We're looking forward to the first warm and comfortable night's sleep in a while.