We recently moved into a house that had a new furnace which had been installed by Heatmaster. During a cold snap we discovered it wasn't quite heating properly, at which point I contacted Dmitri for service. They were at our house a few hours later to diagnose the problem, and when the initial fix didn't do the trick, they came back the next day to complete the repair.
As the furnace is still under warranty we only had to pay a reasonable service fee, and everything else was covered. I was very impressed with their quick response time and friendly, knowledgeable service. I would certainly use Heatmaster again!