Circuit including supercapacitor for supplying power to leak detection circuitry and controller in water heater

A method comprising:

• controlling, by a controller, ignition of a flame;
• converting, by a first power converter of voltage control circuitry, a voltage from one or both of a supercapacitor and a battery to a predetermined voltage;
• converting, by a second power converter of the voltage control circuitry, a voltage from a thermoelectric device to the predetermined voltage;
• charging, by charging circuitry of the voltage control circuitry, the supercapacitor using the predetermined voltage from one or both of the first power converter and the second power converter;
• and
• supplying, by one or both of the first power converter and the second power converter, the predetermined voltage to the controller.

A circuit comprising:

• a first power converter configured to convert a voltage from one or both of a supercapacitor and
• a pre-charged power source to a predetermined voltage;
• a second power converter configured to convert a voltage from a thermoelectric device to the predetermined voltage;
• and
• a charging circuit configured to charge the supercapacitor using the predetermined voltage from one or both of the first power converter and the second power converter,
• wherein one or both of the first power converter and the second power converter are configured to supply the predetermined voltage to a controller.