This disclosure is related to devices, systems, and techniques for outputting an alarm signal in response to detecting a leak in a water heater device. For example, a water heater device includes a leak sensor, an intermittent pilot light, and a circuit. The circuit includes processing circuitry configured to receive, from the leak sensor, an electrical signal including information indicative of a leak in the water heater device, activate, based on the electrical signal including information indicative of the leak, an alarm device, where the alarm device is powered for at least a period of time by a power source, where the power source is configured to receive energy from a thermoelectric device, and maintain an amount of energy stored by the power source so that the amount of energy is sufficient for the power source to supply energy to the alarm device.

A water heater system includes a controller configured to integrate control of both recovery and recirculation operations of a recovery pump and a recirculation pump. As such, a separate device, installation location, and power source (e.g., available outlet) is not needed with the controller. Because a single controller is configured to control both recovery and recirculation operations, additional control functions are available. The controller may be in communication with an internal controller of the water heater and configured to receive an error notification upon abnormal operation of the water heater. The controller can stop recovery and recirculation operations in response to an error notification, unlike with traditional water heating systems which may otherwise continue to function. The recovery and recirculation operations are based on a setpoint temperature of the water heater such that changes made to the setpoint temperature will automatically adjust in the recovery and recirculation operations.

A water heater monitoring and notification method includes determining, by a controller of a water heater system, a deviation of a duration of a pre-purge operation from a pre-purge duration average value. The method further includes determining, by the controller of the water heater system, a deviation of a flame current from a flame current average value and determining, by the controller of the water heater system, a deviation of a pulse-width-modulation (PWM) parameter from a PWM parameter average value. The method also includes providing a notification related to a combustion system of the water heater system based on at least the deviation of the duration of the pre-purge operation from the pre-purge duration average value, the deviation of the flame current from the flame current average value, and the deviation of the PWM parameter from the PWM parameter average value.

An automatically flushing water heater maintenance system may be provided, the system including a water heater and a water heater controller. The water heater may include an inlet, an outlet, and a flush outlet having a first control valve in flow communication therewith. The first control valve may be configured to control a flow of water and sediment through the flush outlet out of the water heater. The water heater controller may be configured to communicate with the first control valve by transmitting a first control signal to the first control valve, the first control signal configured to cause the first control valve to open or close as part of an automatic flushing process. As a result of the flushing, the useful life of the water heater may be extended, and/or water heater leakage alleviated. Insurance discounts may be provided based upon using the automatic water heater flushing functionality.

When a voltage signal is input to input terminals as a positive voltage, the voltage conversion circuit generates a control voltage proportional to an input voltage by a voltage-dividing circuit according to resistance elements, a voltage follower circuit according to an operational amplifier, and a voltage-dividing circuit according to resistance elements. When a voltage signal is input to the input terminals as a negative voltage, since the operational amplifier outputs a power supply voltage according to an input of the negative voltage, the voltage conversion circuit generates a predetermined positive voltage obtained by dividing the power supply voltage by the resistance elements as the control voltage. The predetermined positive voltage is higher than a voltage range of the control voltage when the voltage signal is input as the positive voltage.

A water heater includes a leak detection system. The leak detection system includes a leak sensor assembly that is disposed in a bottom pan of the water heater. The leak sensor assembly includes a sensor housing that has a sensor channel that is formed therein such that the sensor channel is disposed at an elevation from a base of the bottom pan when the sensor housing is disposed on the base of the bottom pan. Further, the leak sensor assembly includes a leak sensor that is disposed in the sensor channel of the sensor housing. The leak sensor detects water that leaks from the water heater and accumulates in the bottom pan when a level of the water in the bottom pan rises to the elevation of the sensor channel and the leak sensor that is disposed therein.

A switch assembly includes an automatic type 11 switch having 1 and 2 contacts and 3 and 4 contacts with the 2 and 3 contacts being shorted together, configured to respond to a water level of a boiler, short the 1 and 2 contacts when the water level is high, short the 3 and 4 contacts when the water level is low; and an electronic circuit board having a processor configured to sense signaling containing information about the 1, 2/3 and 4 contacts, and provide control signaling containing information about the water level of the boiler. The electronic circuit board also includes a relay configured to respond to the control signaling, and turn the relay on/off.

A method of determining presence of a flame in a furnace of a heating, ventilation, and air conditioning (HVAC) system. The method comprises determining, using a controller, whether a processor signal (G) is active, responsive to a determination that the processor signal (G) is active, determining, using the controller prior to assertion of a flame-test input control signal, an output state of a first comparator, responsive to a determination that the output state of the first comparator is high, determining, using the controller prior to assertion of the flame-test input control signal, an output state of a second comparator, and responsive to a determination that the output state of the second comparator is low, transmitting, using the controller, a notification that a flame is present.

A combustion gas supply system and method includes: a cyclonic air filter (or separator), a blower having an inlet and an outlet, and a combustible gas inlet, wherein the cyclonic air filter, the blower, and the combustible gas inlet are in fluid communication.

A control system for controlling a gas powered appliance includes a hot surface igniter, an igniter relay, and an integrity detection circuit. The integrity detection circuit is configured to be coupled to a power source, the igniter relay, and the hot surface igniter to produce an output indicative of the integrity of the hot surface igniter and the igniter relay. The integrity detection circuit is configured to output a first voltage when the igniter relay is closed and output a second voltage different from the first voltage when the hot surface igniter is in a non-short circuit failure condition.