Abstract: A system for monitoring carbon monoxide in an environment which includes an apparatus emitting carbon monoxide, such as an internal combustion engine. A carbon monoxide sensor measures a concentration of carbon monoxide in the environment and provides an electrical signal to a processor that is representative of the measured concentration of carbon monoxide. The processor determines the concentration of carbon monoxide corresponding to the electrical signal, provides an output signal at or above predetermined carbon monoxide concentration thresholds, calculates an estimated carboxyhemoglobin level for the operator corresponding to the carbon monoxide concentrations calculated over time, and provides an output signal at or above predetermined carboxyhemoglobin thresholds. The signals are then received by one or more devices which provide textual, visual, and/or audible warnings indicating that environmental concentrations of carbon monoxide have caused a predetermined warning threshold to be met or exceeded.

Abstract: An indicator junction module for connecting the electrical components of a pressure washer for dispensing a cleaning fluid under pressure. The indicator junction module includes terminal connectors for receiving leads from the components and indicator circuits corresponding to the components. At least one of the indicator circuits has one of its terminals electrically connected to an indicator device and the other of its terminals electrically connected to another indicator circuit. Each indicator device provides a visual indication of a condition of the corresponding component. The indicator junction module also includes an enclosure for enclosing the indicator circuits wherein the indicator devices are visible from outside the enclosure to an operator of the pressure washer and a portion of each terminal connector is external to the enclosure.

Abstract: A high pressure washer of this invention comprises a heat exchanger for heating a cleaning fluid, and a dispenser for dispensing heated cleaning fluid under pressure onto a surface to clean it. The heat exchanger comprises a tubular casing and a generally coaxial tubular heat shield inside the casing defining a combustion chamber. A burner is mounted adjacent a first end wall of the casing for discharging flames and hot combustion gases into the combustion chamber. A heating coil inside the casing extends longitudinally with respect to the casing for containing cleaning fluid to be heated. The heating coil comprises a length of unfinned tubing disposed in a gap between the heat shield and a second end wall of the casing, and a length of finned tubing in the annular space between the heat shield and the casing. The burner is operable to emit flame and hot gases of combustion into said combustion chamber in a direction toward the second end wall of the casing.