Patent ID: 8038081

Claim:
A mobile power washer comprising: a wheeled trailer carrying a water supply system including a water supply tank, a delivery device, and a pump that supplies water from the water supply tank to the delivery device, a heating system comprising a fluid circuit including a fuel fired heater for heating fluid in the fluid circuit, and a heat exchanger for providing heat exchange between heated fluid in the fluid circuit and water in the water supply system, wherein the water supply system includes a buffer tank connected to receive water from a first point in the water supply system situated downstream of the heat exchanger and the pump and upstream of the delivery device, and connected to deliver water to a second point in the water supply system situated between the water supply tank and the pump, and wherein a mixer valve is provided at the second point of the water supply system, the mixer valve having a first inlet connected to the water supply tank, a second inlet connected to the buffer tank, and an outlet connected to the delivery device via the heat exchanger and the pump.