Abstract: A combustion system configured to receive fuel from a plurality of fuel sources, wherein the combustion system includes a burner, a shutter, a fuel selector, and an electronic controller configured to receive an indication of a selected fuel type from the fuel selector and output instructions for the shutter to adjust to a shutter position associated with the selected fuel type, the shutter position being configured to provide a predetermined supply of air to thereby effect an air-to-fuel ratio associated with combustion of the selected fuel type.

Abstract: The disclosed technology includes an on-demand water heater which uses an electric heat source to heat the water. The on-demand water heater can have a low fluid capacity heating chamber which has an inlet and an outlet, an electric heat source for heating the water, and a controller to control the electric heat source and maintain the temperature of the water at a predetermined temperature setting. The on-demand water heater can be powered by a direct current power source. The on-demand water heater can also utilize a solar thermal system to provide additional heat to the water.

Abstract: System and methods for controlling operating state of a heat transfer system are disclosed herein. The heat transfer system can include temperature sensor positioned at the fluid inlet line and the fluid outlet line and a heat exchanger between the fluid inlet line and the fluid outlet line. The heat transfer system can include a processor communicatively coupled to the first temperature sensor and the second temperature sensor. The processor can determine an inlet temperature of water flowing in the fluid inlet line and outlet temperature of water flowing in the fluid outlet line and can determine a delta temperature based on difference between the inlet temperature and the outlet temperature. Based on the inlet temperature and the delta temperature, the processor can determine an operating state of the heat transfer system.

Abstract: System and methods for controlling operating state of a heat transfer system are disclosed herein. The heat transfer system can include temperature sensor positioned at the fluid inlet line and the fluid outlet line and a heat exchanger between the fluid inlet line and the fluid outlet line. The heat transfer system can include a processor communicatively coupled to the first temperature sensor and the second temperature sensor. The processor can determine an inlet temperature of water flowing in the fluid inlet line and outlet temperature of water flowing in the fluid outlet line and can determine a delta temperature based on difference between the inlet temperature and the outlet temperature. Based on the inlet temperature and the delta temperature, the processor can determine an operating state of the heat transfer system.