Abstract: A gas valve assembly includes a gas valve and a control circuit. The gas valve is configured for variably controlling a flow of gas through the gas valve assembly. The control circuit includes a controller programmed to determine a first setting for the gas valve in response to a received commanded flow, adjust the first setting to a second setting based on a measured temperature when the measured temperature is one that may induce changes to the flow of gas through the gas valve assembly, and control the gas valve based on the second setting.

Abstract: A coaxial gas valve assembly includes a gas inlet, a gas outlet, a valve tube, and a shaft member. A main valve is movable between a closed position and an open position (broadly, openable and closable). A main spring is positioned to resiliently bias the main valve in its closed position. A redundant valve is movable between a closed position and an open position (broadly, openable and closable). A redundant spring is positioned to resiliently bias the redundant valve in its closed position. A solenoid coil is positioned to electromagnetically move the shaft member within the valve tube. A balance diaphragm is connected to the valve tube. A gas path through at least the valve tube allows gas flow from a first side of the balance diaphragm to a second side of the balance diaphragm to reduce a pressure difference between the first and second sides of the balance diaphragm.

Abstract: A method of controlling a gas powered water heater includes attempting to pick a main gas valve of the main burner using a first pick method. The first pick method includes closing a switch of a valve pick system to couple a capacitor of the valve pick system to the main gas valve for a first length of time to discharge energy stored in the capacitor to the main gas valve, and opening the switch of the valve pick system after the energy stored in the capacitor is discharged to the main gas valve. The controller determines if the main gas valve is open after using the first pick method. When the controller determines the main gas valve is not open, the controller attempts to pick the main gas valve using a second pick method different than the first pick method.

Abstract: A processor for a controller of a water heater is configured to receive water heater control parameters and an output from a sensor indicating a measured temperature of water in the water heater. The processor is also configured to determine whether to enter an anti-stacking control mode or to enter a demand anticipation control mode. In the anti-stacking control mode the processor is configured to initiate a call for heat when the measured temperature reaches a trigger temperature, calculate a burner on delay value and set a second timer with the calculated value, and calculate a reduced activation time. In the demand anticipation control mode the processor is configured to increase the variable offset based on a frequency of the demand anticipation control mode being activated, initiate a call for heat, and control, based on the reduced activation time or the increased offset value, the burner.

Abstract: An automatic pilot lighting system for unattended automatic lighting of a standing pilot may include a powered (e.g., battery powered, etc.) circuit. The powered circuit may include an analog timer circuit including a timer switch. A spark ignitor may be coupled with the timer switch. A temperature knob pilot momentary switch may be coupled with the timer switch. An ON/OFF switch may be coupled with the temperature knob pilot momentary switch and the timer switch. The ON/OFF switch may be configured to be operable for selectively disabling and enabling a power source. The analog timer circuit may be configured to be selectively activatable for applying voltage from the power source via the ON/OFF switch for pilot hold voltage and spark ignition for an amount of time sufficient to allow for unattended automatic lighting of the standing pilot and sufficient voltage generation to support standalone operation.

Abstract: A method of controlling a gas powered water heater includes attempting to pick a main gas valve of the main burner using a first pick method. The first pick method includes closing a switch of a valve pick system to couple a capacitor of the valve pick system to the main gas valve for a first length of time to discharge energy stored in the capacitor to the main gas valve, and opening the switch of the valve pick system after the energy stored in the capacitor is discharged to the main gas valve. The controller determines if the main gas valve is open after using the first pick method. When the controller determines the main gas valve is not open, the controller attempts to pick the main gas valve using a second pick method different than the first pick method.

Abstract: A processor for a controller of a water heater is configured to receive water heater control parameters and an output from a sensor indicating a measured temperature of water in the water heater. The processor is also configured to determine whether to enter an anti-stacking control mode or to enter a demand anticipation control mode. In the anti-stacking control mode the processor is configured to initiate a call for heat when the measured temperature reaches a trigger temperature, calculate a burner on delay value and set a second timer with the calculated value, and calculate a reduced activation time. In the demand anticipation control mode the processor is configured to increase the variable offset based on a frequency of the demand anticipation control mode being activated, initiate a call for heat, and control, based on the reduced activation time or the increased offset value, the burner.

Abstract: A coaxial gas valve assembly includes a gas inlet, a gas outlet, a valve tube, and a shaft member. A main valve is movable between a closed position and an open position (broadly, openable and closable). A main spring is positioned to resiliently bias the main valve in its closed position. A redundant valve is movable between a closed position and an open position (broadly, openable and closable). A redundant spring is positioned to resiliently bias the redundant valve in its closed position. A solenoid coil is positioned to electromagnetically move the shaft member within the valve tube. A balance diaphragm is connected to the valve tube. A gas path through at least the valve tube allows gas flow from a first side of the balance diaphragm to a second side of the balance diaphragm to reduce a pressure difference between the first and second sides of the balance diaphragm.

Abstract: An automatic pilot lighting system for unattended automatic lighting of a standing pilot may include a powered (e.g., battery powered, etc.) circuit. The powered circuit may include an analog timer circuit including a timer switch. A spark ignitor may be coupled with the timer switch. A temperature knob pilot momentary switch may be coupled with the timer switch. An ON/OFF switch may be coupled with the temperature knob pilot momentary switch and the timer switch. The ON/OFF switch may be configured to be operable for selectively disabling and enabling a power source. The analog timer circuit may be configured to be selectively activatable for applying voltage from the power source via the ON/OFF switch for pilot hold voltage and spark ignition for an amount of time sufficient to allow for unattended automatic lighting of the standing pilot and sufficient voltage generation to support standalone operation.

Abstract: A control circuit for supplying current to actuate a gas valve in an HVAC system includes a solenoid coil adapted to selectively open and close the gas valve, input terminals coupled to receive an AC power input, and a rectifier bridge coupled between the input terminals and the solenoid coil. The rectifier bridge includes four nodes and at least four diodes. The control circuit also includes a capacitor, and a switch coupled in series with the capacitor between a ground potential and a node defined between the rectifier bridge and the solenoid coil. The switch is coupled to selectively electrically connect and disconnect the capacitor in parallel with the solenoid coil to allow the capacitor to smooth the voltage rectified by the rectifier bridge when the switch is on and to inhibit smoothing of the rectified voltage by the capacitor when the switch is off.

Abstract: A control system for controlling a gas powered water heater includes a thermoelectric generator to provide electrical power at a first voltage, a valve control system to selectively hold a main gas valve in an open position, a valve pick system to selectively pick the main gas valve from a closed position to the open position using the electrical power at the first voltage, and a power converter. The controller is electrically powered by a boosted electrical power at the second voltage from the power converter. The controller is communicatively coupled to the valve control system, the valve pick system, and the safety system. The controller is configured to control operation of the main burner and the main gas valve using the valve control system, the valve pick system, and the safety system to provide water heated to substantially a setpoint temperature.

Abstract: A control system for controlling a gas powered water heater includes a power system to provide electrical power, a valve control system to selectively hold a main gas valve in an open position, a valve pick system to selectively pick the main gas valve from a closed position to the open position, a safety system to prevent the valve control system from holding the main gas valve in the open position, and a controller. The controller is electrically powered by the power system and communicatively coupled to the valve control system, the valve pick system, and the safety system. The controller is configured to control operation of the main burner and the main gas valve using the valve control system, the valve pick system, and the safety system to provide water heated to substantially a set point temperature.

Abstract: A safety system for use with a thermoelectric generator is described. The safety system includes a safety switch operatively connected to the thermoelectric generator output. The safety switch has a first state in which the thermoelectric generator can provide a first voltage to a load, and a second state in which the thermoelectric generator cannot output the first voltage to the load and in which the thermoelectric generator can output a second voltage to the load. The second voltage is a non-zero voltage having a magnitude less than the first voltage.

Abstract: A control system for controlling a gas powered water heater includes a thermoelectric generator to provide electrical power at a first voltage, a valve control system to selectively hold a main gas valve in an open position, a valve pick system to selectively pick the main gas valve from a closed position to the open position using the electrical power at the first voltage, and a power converter. The controller is electrically powered by a boosted electrical power at the second voltage from the power converter. The controller is communicatively coupled to the valve control system, the valve pick system, and the safety system. The controller is configured to control operation of the main burner and the main gas valve using the valve control system, the valve pick system, and the safety system to provide water heated to substantially a setpoint temperature.

Abstract: A control system for a gas powered appliance includes a power source to provide electrical power to control at least one electrically actuated gas valve, a valve control system to selectively couple electrical power from the power source to the electrically actuated gas valve, and a controller. The valve control system includes a first switch and a second switch. The first switch and the second switch are electrically connected in series between the power source and the electrically actuated gas valve. The controller is operatively connected to the first switch and the second switch and configured to control the first switch and the second switch to selectively couple power from the power source to the electrically actuated gas valve.

Abstract: A control system for a gas powered appliance includes a power source to provide electrical power to control at least one electrically actuated gas valve, a valve control system to selectively couple electrical power from the power source to the electrically actuated gas valve, and a controller. The valve control system includes a first switch and a second switch. The first switch and the second switch are electrically connected in series between the power source and the electrically actuated gas valve. The controller is operatively connected to the first switch and the second switch and configured to control the first switch and the second switch to selectively couple power from the power source to the electrically actuated gas valve.

Abstract: A safety system for use with a thermoelectric generator is described. The safety system includes a safety switch operatively connected to the thermoelectric generator output. The safety switch has a first state in which the thermoelectric generator can provide a first voltage to a load, and a second state in which the thermoelectric generator cannot output the first voltage to the load and in which the thermoelectric generator can output a second voltage to the load. The second voltage is a non-zero voltage having a magnitude less than the first voltage.

Abstract: A control system for controlling a gas powered water heater includes a power system to provide electrical power, a valve control system to selectively hold a main gas valve in an open position, a valve pick system to selectively pick the main gas valve from a closed position to the open position, a safety system to prevent the valve control system from holding the main gas valve in the open position, and a controller. The controller is electrically powered by the power system and communicatively coupled to the valve control system, the valve pick system, and the safety system. The controller is configured to control operation of the main burner and the main gas valve using the valve control system, the valve pick system, and the safety system to provide water heated to substantially a setpoint temperature.