A hydraulic unit is for use in a multi zone heating system. The hydraulic unit comprises a variable output pump; a plurality of independently controllable valves, each valve being associated with one heating zone; and at least one temperature sensor. Each heating zone receives a heated water supply from a common heat source via the pump. The heating system includes a controller comprising a processor which receives signals from the at least one temperature sensor which processes the signals in accordance with control software. Command signals are sent to the pump and the plurality of independently controllable valves, to vary the flow rate of water from the common heat source to each of the heating zones independently one to another. Remote fault diagnosis and control is also provided.

The disclosed technology includes an on-demand water heater which uses a heat pump to heat the fluid. The on-demand heat pump water heater can have a low fluid capacity heating chamber which has an inlet and an outlet, a heat pump for heating the fluid, and a controller to control the heat pump and maintain the temperature of the fluid at a predetermined temperature. The on-demand heat pump water heater can include one or more temperature sensors, flow sensors, fluid mixing valves, or supplemental heat sources.

An air-conditioning apparatus includes: a heat-source-side device that heats or cools a heat medium; a pump that sucks and transfers the heat medium; use-side heat exchangers; a heat medium circuit; flow rate control devices; indoor-side pressure sensors; a pump inlet-side pressure sensor and/or a pump outlet-side pressure sensor; a flow rate detection device that detects a pump flow rate; and a controller that performs a first operation in which the flow rate control devices are individually opened or closed and data regarding a flow passage resistance at a path related to each of the heat exchangers is obtained, and a second operation in which heat is supplied to indoor air, and calculates calculate flow rates of the heat medium that flows through the heat exchangers in the second operation, from pump flow rates and pressures detected by the pressure sensors in the first and second operations.

A heating and hot water supplying device is provided. The device comprising: a circulation passage that connects a heat exchanger and an external heating terminal; a bypass passage that bypasses the heating terminal by branching from the circulation passage; a hot water supply passage for supplying the hot water heated to a preset hot water supply temperature by the heat exchanger for hot water supply; a control unit that controls operations in which this plurality of units are used; and an operation unit for performing various operations. A distribution means is provided in the branching portion of the bypass passage. The distribution means adjusts the distribution ratio so that each of a heating operation, a hot water supplying operation, and a simultaneous heating and hot water supplying operation is possible. The operation unit is provided with a prohibit switch to prohibit the simultaneous heating and hot water supplying operation.

There is provided a hydronic system for a plurality of zones. The system includes a wiring track. The track has a pair of power conductors for supplying electrical energy therealong and a pair of signal conductors. The signal conductors are in communication with a heat/cold source. The system includes a plurality of zone modules, each corresponding to a respective one of the zones. Each of the zone modules includes leads which connect to respective ones of the conductors. Each of the zone modules includes terminals and conductors configured to selectively connect respective thermostats and zone valves of their zone together, receives signals therefrom and conveys the signals via the signal conductors to the heat/cold source for selectively heating/cooling respective ones of the zones.

A boiler loop system including a primary-secondary piping loop interface apparatus including a flow diversion device, and a drain valve, and a drain port in branches from a circumferential sidewall. In an embodiment, supply branch piping and return branch piping connect the primary-secondary piping loop interface apparatus to a boiler and provide attachment points for auxiliary plumbing equipment. In an embodiment, the boiler loop is integrated into the primary loop.

A valve arrangement including: a valve inlet, a valve outlet arranged downstream of the valve inlet, a first chamber arranged directly downstream of the inlet, and a second chamber arranged between the first chamber and the valve outlet. The valve arrangement further includes a measuring nipple comprising a measuring channel for receiving a measuring device, and a closing arrangement having open positions and a closed position, wherein the closing arrangement in its closed position is configured to prevent fluid communication between the first chamber and the second chamber via the closing arrangement, and wherein the closing arrangement in its open positions is configured to allow for fluid communication between the first chamber and the second chamber via the closing arrangement.

A district energy network interconnecting a plurality of thermal loads and for redistributing thermal energy therebetween, the network comprising: a primary circuit loop for working fluid, at least two thermal loads thermally connected to the primary circuit loop, at least one of the thermal loads being capable of taking heat from the primary circuit loop and at least one of the thermal loads being capable of rejecting heat into the primary circuit loop, an energy centre connected to the loop and capable of acting as a heat source or a heat sink, and a control system adapted to provide to the primary circuit loop a positive or negative thermal input from the energy centre as a balancing thermal input to compensate for net thermal energy lost to or gained from the at least two thermal loads by the primary circuit loop.

A conditioning or heating plant and a process of controlling the plant, wherein plant comprises at least one circuit for distributing a carrier fluid, having a delivery line, a return line, and a plurality of channels directly or indirectly connected to the delivery line and return line and configured for supplying respective environments to be conditioned and/or heated, at least one heat treatment central group placed on the circuit. The plant has, for each of the channels, at least one respective heat exchange unit and at least one flow-rate regulator.

A method for balancing mass flow during production failure or insufficiency in a district heating network comprising a plurality of substations, each substation comprising at least one primary side connected to the district heating network for transferring heat between the district heating network and the substation, a secondary side connected to least one space heating circuit for heating at least one space connected to the substation, and an adjustable valve arranged between the substation and the district heating network, the valve (102) in each substation being controlled by a heat curve f defining a calculated supply temperature (Tsupply, calc) for the space heating circuit on the secondary side of the substation as a function of a measured outdoor temperature (Toutdoor). The method further comprises a step of heat curve compensation for each substation and population compensation for all substations in the population. The result is then used to control the valve in the respective substation.