They installed a hot water on demand system and furnace. The furnace is a Clean Air furnace, and heats the house with the hot water from the HWOD system. It is an outstanding system, providing steady warm heat and hot water without a standing water tank to eat up your gas bill.
Their after-sales service is outstanding. I am huge on the importance of after sales service - I would rather pay more and get the service. I have never seen better.