A water heater is provided that heats water in a storage tank and discharges the heated water. The water heater includes a storage tank configured to store water, at least one first temperature sensor configured to sense a temperature of the water stored in the storage tank, a second temperature sensor configured to sense a temperature related to an outside of the water heater, a first heat exchanger comprising at least one heating element configured to heat the water, a second heat exchanger comprising a heat pump system and configured to heat the water, and a controller configured to control at least one of the first heat exchanger and the second heat exchanger based on a temperature sensed by the second temperature sensor and a set water temperature.

A water heater is provided that heats water in a storage tank and discharges the heated water. The water heater includes a storage tank configured to store water, at least one first temperature sensor configured to sense a temperature of the water stored in the storage tank, a second temperature sensor configured to sense a temperature related to an outside of the water heater, a first heat exchanger comprising at least one heating element configured to heat the water, a second heat exchanger comprising a heat pump system and configured to heat the water, and a controller configured to control at least one of the first heat exchanger and the second heat exchanger based on a temperature sensed by the second temperature sensor and a set water temperature.

In accordance with the principals of the present invention, a furnace unit adapted to be installed in-line with a fuel source of a furnace modulates natural gas or propane to reduce fuel consumption, minimize temperature overshoot, and reduce furnace short cycling. A modulator is contained with the furnace unit. The modulator is in gaseous communication with the in-line gas fuel source. A furnace sensor senses furnace criteria related to the operation of the furnace. A microcontroller receives from the furnace sensor furnace criteria and controls the modulator based on the furnace criteria. In a further aspect of the invention, an environmental sensor can be provided to sense environmental criteria related to the operation of the furnace. In a further aspect of the invention, a base unit in electrical communication with the furnace unit can be provided, the base unit determining energy consumption usage and savings. This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

In accordance with the principals of the present invention, a furnace unit adapted to be installed in-line with a fuel source of a furnace modulates natural gas or propane to reduce fuel consumption, minimize temperature overshoot, and reduce furnace short cycling. A modulator is contained with the furnace unit. The modulator is in gaseous communication with the in-line gas fuel source. A furnace sensor senses furnace criteria related to the operation of the furnace. A microcontroller receives from the furnace sensor furnace criteria and controls the modulator based on the furnace criteria. In a further aspect of the invention, an environmental sensor can be provided to sense environmental criteria related to the operation of the furnace. In a further aspect of the invention, a base unit in electrical communication with the furnace unit can be provided, the base unit determining energy consumption usage and savings. This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

A controller for use in a gas appliance system includes a circuit board, a plurality of connectors and a processor mounted on the circuit board. The processor controls operation of the gas appliance using, in part, at least one connector of the plurality of connectors and control settings for an intermittent pilot (IP) system in response to a user selection to configure the controller to control an IP system, and controls operation of the gas appliance using, in part, at least one connector of the plurality of connectors and control settings for a direct spark ignition (DSI) system in response to a user selection to configure the controller to control a DSI system.

The present disclosure discloses an optimal operation control method of the air-source heat pump and gas-fired heater combined heating system, including constructing a mathematical model of the air-source heat pump and gas-fired heater combined heating system to simulate real time energy consumption; determining a comprehensive evaluation index system of the combined heating system, including primary evaluation indexes of energy conservation, environmental protection and economical efficiency, and secondary evaluation indexes of EER, clean energy utilization rate, carbon dioxide emission and operation cost; calculating indexes through an analytic hierarchy process and then constructing a comprehensive objective function, to determine operation mode when the comprehensive objective function is the maximum by taking the priority of meeting the heating requirement as a principle, so as to achieve the purpose of optimizing the combined heating system, and achieve the combined heating system efficient, energy-saving and environmental protection.

The present disclosure discloses an optimal operation control method of the air-source heat pump and gas-fired heater combined heating system, including constructing a mathematical model of the air-source heat pump and gas-fired heater combined heating system to simulate real time energy consumption; determining a comprehensive evaluation index system of the combined heating system, including primary evaluation indexes of energy conservation, environmental protection and economical efficiency, and secondary evaluation indexes of EER, clean energy utilization rate, carbon dioxide emission and operation cost; calculating indexes through an analytic hierarchy process and then constructing a comprehensive objective function, to determine operation mode when the comprehensive objective function is the maximum by taking the priority of meeting the heating requirement as a principle, so as to achieve the purpose of optimizing the combined heating system, and achieve the combined heating system efficient, energy-saving and environmental protection.

A heat pump system includes a heat pump and an auxiliary heat source. A heating coefficient of performance is determined for the heat pump based on ambient outdoor air temperatures, and the heat pump is operated to heat a process fluid an output temperature based on the heating coefficient of performance and a reference heating coefficient of performance. The auxiliary heat source can be operated to bring the process fluid to a target temperature for heating a load, with the target temperature being a function of the ambient outdoor air temperatures.

A water heating system has an exterior heat pump water heater supplying heated water to a storage tank connected to a recirculation loop with a swing tank. A controller receives measured ambient air temperature from an outdoor temperature sensor mounted exterior to the building near the heat pump water heater. The swing tank has three banks of resistance heating elements arranged into first, second and third heating sectors controlled by the controller. When ambient temperatures are more than about 8 degrees Fahrenheit above freezing, only the first heating sector heating elements are activated when heating is called for. When ambient temperature is less than this level and greater than about 8 degrees Fahrenheit below freezing, the heating elements in the first and second heating sectors are activated. When the ambient temperature is less than this, all heating sectors are activated, thus providing advantageous levels of hot water heating efficiency.

A water heating system has an exterior heat pump water heater supplying heated water to a storage tank connected to a recirculation loop with a swing tank. A controller receives measured ambient air temperature from an outdoor temperature sensor mounted exterior to the building near the heat pump water heater. The swing tank has three banks of resistance heating elements arranged into first, second and third heating sectors controlled by the controller. When ambient temperatures are more than about 8 degrees Fahrenheit above freezing, only the first heating sector heating elements are activated when heating is called for. When ambient temperature is less than this level and greater than about 8 degrees Fahrenheit below freezing, the heating elements in the first and second heating sectors are activated. When the ambient temperature is less than this, all heating sectors are activated, thus providing advantageous levels of hot water heating efficiency.