Sellers and installers of hydronic systems in the state of Washington now have an online source for getting their advertising message out to prospective customers. A source guide at http://energy.sourceguides.com/businesses/byGeo/US/byS/WA/byP/hydronic/hydronic.shtml lists hydronic businesses with a description of their equipment/services.

The Web site is sponsored by Momentum Technologies LLC, a privately held company headquartered in Glendale, Colo., with offices in Mountain View, Calif., and Denver. The company is a provider of electronic marketplace solutions for both business-to-business and business-to-consumer vertical markets.

Contractors interested in listing their businesses can visit the Web site for details.