Financing a Gas Boiler

When I changed from oil to gas in 1985, Brooklyn Union Gas offered a great financing package to cover the changeover, installation, and the cost of the new equipment. It’s time to install a state-of-the-art new gas boiler and water heater, and I need a creative way to finance it. I don’t want to take out a second mortgage or a home loan. Anyone know of a government or utility company program that would offer a loan to cover this upgrade?