A method of heating water in a water storage tank. The method includes: selecting an outlet port and an inlet port from at least three ports located in the tank at different heights along a vertical direction. The outlet port is below the inlet port. The method further includes extracting water from the outlet port, supplying the extracted water to an external heat exchanger configured for heating the extracted water, and delivering heated water from the heat exchanger to the selected inlet port.

An aircraft water supply system supplies water to a water discharge port in an aircraft. A cold water flow path supplies cold water to the water discharge port. A hot water flow path supplies hot water to the water discharge port. A first control valve adjusts the flow rate of cold water flowing through the cold water flow path. A second control valve adjusts the flow rate of hot water flowing through the hot water flow path. A temperature sensor detects the water temperature at any point up to the water discharge port. A flow control unit controls the opening/closing state of the first control valve and the second control valve based on the water temperature detected by the temperature sensor.

A hot water circulation system comprises a water heater having a cold-water inlet and a hot water outlet. A water pump circulates water through the water heater to produce hot water. The hot water is circulated to a thermal bypass valve, which is configured to close when hot water contacts a heat activated seal. A bypass circuit is coupled between the hot water outlet and the cold water inlet of the water heater. The bypass circuit prevents hot water from circulating from the hot water outlet to the cold-water inlet when the thermal bypass valve is open and promotes circulating hot water from the hot water outlet to the cold water inlet when the thermal bypass valve is closed. Upon a temperature sensor sensing hot water entering the cold-water inlet, the water heater turns of the water pump.

An electric heating device for emitting a heated air flow, in particular for a sanitary room or washroom in a rail-borne vehicle, includes an air duct, a fan generating the air flow, a heating element heating the air flow and a first over-temperature switch. The first over-temperature switch can reversibly switch off the heating element when a first over-temperature is exceeded. A second over-temperature switch can irreversibly switch off the heating element when a second over-temperature is exceeded. The second over-temperature switch is disposed in a recess, depression or opening formed in the air duct. The second over-temperature switch has a disconnect or isolating switch to be thermally triggered for switching off the heating element. The thermally triggered disconnect or isolating switch can be triggered by a glass sphere or bead that breaks when the second over-temperature is exceeded.

An air conditioning system, a set temperature determining device determines a target temperature of water to be supplied to an indoor heat exchanger, based on [“target outflow temperature”=“current outflow temperature”+((“inlet and outlet temperature difference”/“indoor and outdoor temperature difference”)דset temperature difference”)]. The indoor and outdoor temperature difference is a difference between an indoor temperature and an outdoor temperature, the inlet and outlet temperature difference is a difference between temperatures of water at the inlet side and the outlet side of an intermediate heat exchanger, and the set temperature difference is a difference between an indoor temperature and a set temperature. A control device controls an outdoor unit in response to the target temperature determined by the set temperature determining device.

Systems and methods for preventing freeze damage to heating system pipes are provided. In some embodiments, systems for preventing freeze damage to heating system pipes that carry a liquid used to heat a heated space and that are exposed to freezing temperatures outside of the heated space are provided, the systems comprising: a hardware controller that causes the liquid to be circulated through the heating system pipes irrespective of the air temperature in the heated space.

A system, apparatus, and method for a differential temperature managed integral, free standing, hydronic heating appliance uses a high-mass heat source coupled to a single, highly-efficient, variable speed, Electronically Commutated Motor (ECM)-driven Delta-T stand-alone system circulator which feeds one or more zone valves governing flow to one or more hydronic zones. Components are integrated into simplified, compact, assemblies. Zone valve packaging of a compact header improves hydronic performance (head pressure reduction and increased flow), complementing zone valve performance and reducing zone valve wiring labor and material content. Returns have full port valves and the boiler includes isolation valves. All manually activated valves are full port. This can include full port boiler isolation valves, circulator isolation valves and return valves. Paralleled, ganged, alignment of state-indicating-lamped zone valves provides rapid, functional indication of component and system performance while the need for a zone valve panel commonly found on hydronic heating systems is negated.

Provided is a heating device for a hot water mat that can minimize noise by a check valve for controlling flow of liquid. The heating device for a hot water mat includes: a water tank having a tub for keeping liquid and a discharge hole formed through a side of a lower portion to discharge the liquid in the tub; a heating module connected to the discharge hole and heating liquid; a separator disposed in the water tank, dividing the tub in to a first compartment at a lower portion and a second compartment at an upper portion, and having a connection hole for connecting the first compartment and the second compartment to each other; and a check valve disposed in the first compartment and opening and closing the connection hole by moving up and down by buoyancy from the liquid in the first compartment.

A process and apparatus for monitoring and/or controlling at least one air conditioning and/or heating plant (1) including a delivery line (3), a return line (4) and service lines (5) hydraulically interposed between the delivery line (3) and the return line (4), each service line (5) comprising at least one thermal exchange unit (7). The process detects a value (φ) of the flow rate of the carrier fluid traversing the thermal exchange unit (7), and determines a temperature difference (ΔT) between the temperature (Tt1) of the carrier fluid, at the first section (5a), detected at a first instant (t1), and the temperature (Tt2) of the carrier fluid, at the second section (5b), detected at a second instant (t2).

A method for controlling a distribution temperature of domestic hot water implemented in a management unit of an installation for producing domestic hot water and including steps for obtaining mean temperatures of the distributed hot water, determined by time ranges and measured by one or more divisional distribution meters in the course of a reference period; obtaining a minimum value and a maximum value of these temperature averages in order to determine a temperature condition of the distributed hot water from at least the maximum value or the minimum value, and from at least one predefined temperature threshold, and, if the distribution condition determined is met, sending a sequence controlling the production temperature to the production installation. Also, a distribution installation, a distribution meter and a unit for managing the distribution of domestic hot water.