A tankless water heater including a water inlet, a water outlet, a conductivity sensor, a temperature sensor, and a heating chamber connected to the water inlet and the water outlet wherein the heating chamber is configured to heat a flow of water received from the water inlet and output the flow of water to the water outlet. The water heating system can further include a controller communicably coupled to the conductivity sensor and the temperature sensor, where the controller calculates an adjusted conductivity of a flow of water through the water heater.

A lid for a heat generating device in which the heat generating device has a body with a combustion chamber disposed therein. The lid includes an air moving device, an air intake housing, and a hinge. The air moving device is configured to generate a flow of air. The air intake housing is disposed between the lid and the air moving device. The air intake housing extends out from the lid to cantilever the air moving device out from the lid. The hinge is disposed between the lid and the body and proximal to the air intake housing. The hinge is configured to provide a pivot for the lid. A weight of the air moving device counter balances at least a portion of a weight of the lid to ease pivoting of the lid into an open position.

A condensation tray for condensing tankless water heaters is disclosed. The tray can include a plurality of peaks and valleys. The peaks can divert condensate runoff from a secondary heat exchanger into the valleys so as to prevent the condensate from falling on a primary heat exchanger. The tray includes gas apertures that enable combustion gases to pass through the tray and across the secondary heat exchanger. Overhangs on the peaks can prevent the condensate from draining through the gas apertures.

Disclosed systems and methods relate to a water heater sensor for detecting a corrosion of an anode rod. According to embodiments, a system can include the anode rod in contact with water in a water heater, where the anode rod includes a corrodible sheath having a cavity. The system can include two electrical wires, where first ends of the two electrical wires, disposed within the cavity, are configured to come in contact with the water when the corrodible sheath of the anode rod corrodes to a certain point. The system can include a controller coupled to second ends of the two electrical wires, where the controller can detect whether the water is in contact with the first ends of the two electrical wires. The system can include an indicator to provide an indication when the water is in contact with the first ends of the two electrical wires.

A combined heat and power system generates energy and efficiently captures a percentage of such energy that would otherwise be lost to, among other things, control the temperature and humidity of a house or dwelling.

Disclosed are an air duct assembly and a fan heater applying in the air duct assembly, which includes a volute tongue positioned in the volute forms an air duct with the volute. The air duct is configured with an air inlet and an air outlet. A cross-flow wind turbine positioned in the air duct introduce the airflow into the air duct from the air inlet, and blow out the airflow in the air duct through the air outlet. The volute includes a first volute tongue member, the size of the angle between the line connecting the root portion M of the first volute tongue member to the axis O of the cross-flow wind turbine and the line connecting the root portion N of the second volute tongue member to the axis O of the cross-flow wind turbine on the same cross-section is from 110° to 170°.

Aspects of the invention provide a heat exchanger that includes a shell coupled to a top tube sheet and a bottom tube sheet. The shell at least partially defines an interior region. The heat exchanger also includes a burner positioned to deliver combustion gases into the interior region. A plurality of tubes, configured to circulate a fluid therein, extend through the interior region around the burner. The heat exchanger further includes a divider that extends within the interior region from the top tube sheet to the bottom tube sheet and between one of the plurality of tubes and another non-adjacent tube of the plurality of tubes. The divider and the plurality of tubes define a receiving section of the interior region for receiving combustion gases from the burner and an exhaust section of the interior region in fluid communication with a combustion gas vent.

A water heater appliance includes a tank extending along a vertical direction between a top end wall and a bottom end wall and a dip tube extending from an inlet end to an outlet end. The inlet end of the dip tube is coupled to a cold water inlet in the top end wall of the tank. The outlet end of the dip tube may be positioned in a bottom corner of the tank and/or positioned at an outer perimeter of the bottom end wall.

According to the present invention, disclosed is a pipe fluid heat exchange flat pipe, which has a cross section having a width direction size that is larger than the size in the height direction thereof, extends in a longitudinal direction, and has a plurality of flat parts and curved parts that are alternately formed, wherein a plurality of lower guides protruding from the inner lower surface of the flat pipe toward the upper side thereof and upper guides protruding from the inner upper surface of the flat pipe toward the lower side thereof are alternately provided in the width direction of the flat pipe, and either the lower guide or the upper guide has an overlapping part overlapped with the other from either of the adjacent lower guide or upper guide in the height direction of the flat pipe.

Disclosed in an embodiment is a fluid heater including a main body including a partitioning part having a plate shape and a flow passage forming part forming a flow passage on the other surface of the partitioning part, a heating plate disposed on the flow passage forming part and having a plate shape and including a heating pattern having a shape corresponding to the flow passage, a circuit board disposed on one surface of the partitioning part and configured to control the heating pattern to generate heat, and a bus bar electrically connecting the heating pattern and the circuit board, wherein the flow passage forming part includes a turning vane disposed in a curved flow passage of the flow passage.