When the city was redoing our water mains, we had to add reservoirs & gauges to accommodate the new closed system. Dan informed me that he could just add the gauge, as others were doing, but that it might not be adequate. He also stated that my hot water tank was near the end of its life. Since I had been thinking that the tank was old, and worried that it might die on me, I had Dan change it as well. The work was done efficiently, in a timely manner, and all stages were explained to me. Dan did such a good job I had him come back to service my furnace. Once this was done, Dan recommended a feature that would give me better heat exchange, but he also mentioned that my old furnace was a great workhorse, and did not need replacing. The added feature would just make better use of the heat exchange.