One or more techniques and/or systems are disclosed for a pellet stove that can be controlled remotely using a wireless communication network. A control unit can comprise memory and a processor to run programs and process other data. A wireless communications module can be used to send/receive, current and historical status information over a wireless network to/from a user's computing device, such as a smart phone. The user can receive the information about the status of the stove, and can monitor and send updates regarding the functionality of the stove. For example, a preset heating program can be activated remotely based on time and temperature, and the user can view and adjust the temperature, can adjust a fan speed, a fueling rate, and other functions of the stove.

The present disclosure provides for a recirculating flow controller that is operably coupled to a flow switch and to a recirculation pump. The recirculating flow controller determines that hot water has begun to flow by way of the connection with the flow switch. In response, the recirculating flow controller activates the recirculation pump to circulate hot water from a water heater. The recirculating flow controller can activate the recirculation pump for a predetermined duration. The flow switch can be configured to sense flow in a hot water line connected to a water heater. The flow switch can be activated by turning on any hot water faucet connected to the water heater.

Methods and systems are provided for managing environmental conditions and energy usage associated with a site. One exemplary method of regulating an environment condition at a site involves a server receiving environmental measurement data from a monitoring system at the site via a network, determining an action for an electrical appliance at the site based at least in part on the environmental measurement data and one or more monitoring rules associated with the site, and providing an indication of the action to an actuator for the electrical appliance.

A district energy distributing system is disclosed. The system comprises a geothermal heat source system comprising a geothermal heat source and a feed conduit for a flow of geothermally heated water from the geothermal heat source. The system further comprises a district feed conduit, a district return conduit and a plurality of local heating systems, each having an inlet connected to the district feed conduit and an outlet connected to the district return conduit, wherein each local heating system is configured to provide hot water and/or comfort heating to a building, A central heat exchanger is connected to the feed conduit of the geothermal heat source system such that an incoming flow of geothermally heated water is provided to the central heat exchanger.

A tankless water heater (TWH) isolation valve includes a valve body having a plug valve port, a TWH port, a water distribution system port and a drain port. A plug valve includes at least one plug seal. The plug valve is controlled by a rotatable plug valve handle. The plug valve is disposed through the plug valve port and within the valve body. The rotatable plug valve handle includes a first plug valve handle position and a different rotated second plug valve handle position. In a normal operating mode in the first plug valve handle position, the TWH port is fluidly coupled to both of the drain port and the water system distribution port. In a drain mode, the TWH port is fluidly coupled to the drain port, and the water system distribution port is closed to the TWH port as blocked by the plug seal.

A heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor configured to detect an outdoor temperature, a second temperature sensor provided in heating pipes connected to a heating device that performs indoor heating and configured to detect a temperature of fluid flowing through the heating pipes, an outdoor heat exchanger configured to perform heat exchange between outdoor air and a refrigerant, a third temperature sensor configured to detect a temperature of the outdoor heat exchanger, and a controller. The controller may be configured to: control power to a boiler and/or to the compressor based on sensing values of the first, second, and third temperature sensors, calculate an expected efficiency of the heat pump based on the sensing value of the first temperature sensor and an initial target temperature, and control power to the boiler based on the expected efficiency.

Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

A monitoring system that is configured to monitor a property is disclosed. The monitoring system includes a sensor that is configured to generate sensor data that reflects an attribute of the property. The monitoring system further includes a hot water circulation system that is configured to selectively circulate hot water between a hot water source and at least one of multiple locations of the property. The monitoring system further includes a monitor control unit that is configured to receive and analyze the sensor data. The monitor control unit is further configured to determine to circulate hot water between the hot water source and a first location of the multiple locations of the property and to bypass circulating hot water between the hot water source and a second location of the multiple locations of the property.

A constant-temperature water supply system employing a carbon dioxide heat pump includes a primary side loop, a secondary side water supply pipeline, a carbon dioxide heat pump water heater in the primary side loop, and a heat exchanger between the primary side loop and the secondary side water supply pipeline; the temperature of return water is detected and the temperature of a return water tank is detected, so even if the temperature of return water flowing out of a first heat exchange tube fluctuates, the return water can be input at a position in the return water tank having a close temperature, such that water in the return water tank is always in a stably layered state, and therefore allows for constant-temperature water supply.

A modular hydronic system core system and method includes a hydronic fluid flow conduit with closely spaced tees and distribution supply and return portions on a substrate. A supply manifold is coupled to branch feeders that support a circulator pump or zone valve. An ECM circulator along the conduit includes a Bluetooth transmitter to capture and transmit fluid flow rate and pressure. A return manifold includes branch returns with purge/shutoff valves. The branch feeders and returns are connectable to a distribution system having heating elements. Air and dirt separators, and an iron remover remove air, dirt and iron from the fluid. An expansion tank bracket supports a pressure gauge and expansion tank. A zone relay is coupled to the ECM circulator and zone valves on the branch feeders, and includes thermostat terminals. The zone relay captures inputs from the thermostats to control operation of the ECM circulator and zone valves.