DFW Pipe & Plumbing replaced a Rinnai tankless water heater with another one. They are one of the largest factory-authorized installers of Rinnai. I lost my hot water so I called DFW Pipe & Plumbing. The office staff was very polite. I think I talked directly to Patrick, the owner, who came out and surveyed my problem at no charge. He determined that the water heater needed to be replaced. The plumbers that came out to the house were very professional skilled tradesmen. They had the new tankless water heater installed in a couple of hours. DFW Pipe & Plumbing was very transparent in terms of pricing, and they were very competitive with their pricing. I would definitely recommend DFW Pipe & Plumbing to others!