US Patent 9724734 High efficiency hot water pressure washer

An improved hot water pressure washer utilizes a combination of technologies to achieve lower emission levels and increased operational efficiency. A forced air natural gas or forced air oil burner utilizes a flue gas and recirculation line to lower carbon monoxide and NOx emissions from a burner. A flue gas heat exchanger is utilized to lower the temperature of the exhaust gas. The lower exhaust gas temperatures allow for lower cost materials to be utilized. The efficiency levels of a hot water pressure washer are increased over known devices.