An apparatus and system for a combination space and water heater including a controller device and a method for control. The controller device is a self-contained system that can be added to, or in combination with, existing water heaters and hydronic air heating systems using standard plumbing connections, and provides a potable water system without any need of an intermediary heat exchanger. The controller device automatically monitors a heating capacity of the water heater and the hydronic heating coil over time, and correlates measured heating loads with one or more environmental temperatures, thermostats, user settings, and/or a supplemental heating system.

When a heating operation mode using a heating unit is specified and when a hot water supply request using the hot water in a hot water storage tank does not occur, an air conditioning apparatus transmits a first selection signal for selecting the heating unit to a three-way valve. When the heating operation mode is specified and when the hot water supply request occurs, the air conditioning apparatus transmits, to the three-way valve, a second selection signal for changing a destination of circulation of secondary refrigerant from the heating unit to a coil heat exchanger, and transmits an operation start signal to a refrigerant indoor unit.

A heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor provided in heating pipes connected to a heating device that heats an indoor space to sense a temperature of fluid flowing through the heating pipes, and a controller. The controller may be configured to determine whether a boiler is operating to heat an indoor space or is operating to supply hot water based on a sensing value of the first temperature sensor. The compressor may operate when the controller determines that the boiler is not operating to heat the indoor space and/or determines that the boiler is operating to supply hot water.

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.

A supplemental heating system includes an enclosure that encloses a primary heating device. The enclosure includes an inlet damper, an outlet damper, and an intermediate damper. In an idle state, the inlet damper and outlet damper are open while the intermediate damper is closed. In an active state, the inlet damper and outlet damper are closed while the intermediate damper is open, so that air is circulated within the enclosure.

A water mixing system attached to an existing plumbing system supplying ambient temperature water and providing temperature regulated water to a user. The water mixing system includes an insulated water tank, a heat pump connected to the insulated water tank with a heat rejecting radiator inside the insulated water tank and a heat absorbing radiator outside the insulated water tank, a temperature detector in the insulated water tank, and one outlet of the insulated water tank connected to a first inlet of a first dispensing water tank. Having a second inlet to receive the ambient temperature water from the existing plumbing system and at least one dispensing outlet, the first dispensing water tank provides mixed water of a desirable temperature from heated water from the insulated water tank and the ambient temperature water via control of the valves attached to the first inlet and the second inlet.

A water mixing system attached to an existing plumbing system supplying ambient temperature water and providing temperature regulated water to a user. The water mixing system includes an insulated water tank, a heat pump connected to the insulated water tank with a heat rejecting radiator inside the insulated water tank and a heat absorbing radiator outside the insulated water tank, a temperature detector in the insulated water tank, and one outlet of the insulated water tank connected to a first inlet of a first dispensing water tank. Having a second inlet to receive the ambient temperature water from the existing plumbing system and at least one dispensing outlet, the first dispensing water tank provides mixed water of a desirable temperature from heated water from the insulated water tank and the ambient temperature water via control of the valves attached to the first inlet and the second inlet.

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 heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor provided in heating pipes connected to a heating device that heats an indoor space to sense a temperature of fluid flowing through the heating pipes, and a controller. The controller may be configured to determine whether a boiler is operating to heat an indoor space or is operating to supply hot water based on a sensing value of the first temperature sensor. The compressor may operate when the controller determines that the boiler is not operating to heat the indoor space and/or determines that the boiler is operating to supply hot water.

A water heater may operate according to different modes. The water heater may include a storage tank configured to store water, at least one sensor configured to sense a temperature of the water and a temperature related to an outside of the water heater, a first heater assembly (comprising a heating element) configured to heat the water, a first controller configured to control the first heater assembly, a second heater assembly (comprising a heat pump system) configured to heat the water, an inverter connected with the heat pump system, and a second controller configured to control the heat pump system by adjusting an output frequency of the inverter.