A hydronic system and method of use that will maintain normal system operating pressure while also reliably detecting even very small fluid losses in any closed loop fluid heat transfer system is described. The system includes a controller in communication with one or more pressure sensors and optionally one or more temperature sensors that provides one or more notifications when the pressure drops below predetermined levels.

A residential and commercial sewerage, drainage and water disposal system and device that includes a ferrous metal cleanout plug and a pair of magnetic electrical connectors disposed in the cleanout plug, without being in physical contact with one another, where the magnetic electrical connectors are magnetically attached to the interior of the cleanout plug and retain in place an insulator plate, and where the electrical connectors are electrically connected with an alarm/control module capable of emitting and alarm and/or closing the main water supply shut off valve, so that the electrical connectors open or close an electric circuit when the fluid reaches the connectors and activates an alarm and/or and shuts off the water valve, promoting safer sewerage, drainage and water disposal system operation.

A fluid transportation network (1) comprises a plurality of parallel zones (Z1, Z2), fed by a common supply line (L), with a regulating zone valve (V1, V2) in each zone (Z1, Z2) for regulating a flow of fluid (ϕ.sub.1, ϕ.sub.2) through the respective zone (Z1, Z2). A processing unit (RE) receives valve positions (pos.sub.1, pos.sub.2) of the regulating zone valves (V1, V2) and determines and sets an adjusted valve position for a line valve (VE) arranged in the supply line (L), depending on the valve positions (pos.sub.1, pos.sub.2) of the regulating zone valves (V1, V2). A processing unit (RE) further receives a measurement of a total flow of fluid (ϕ.sub.tot) through the supply line (L) and determines and sets adjusted valve positions for the regulating zone valves (V1, V2), depending on the measurement of the total flow of fluid (ϕ.sub.tot) through the supply line (L).

A system for heating a first fluid flow from a first temperature to a second temperature, the system including a hot water supply line for receiving the first fluid flow at a first end and exhausting the first fluid flow at a second end; and a heating system including a heat engine, a thermal battery and a heat exchanger, wherein the thermal battery is configured to be replenished at a point of heat transfer by the heat engine and the hot water supply line is configured to receive heat from the thermal battery via the heat exchanger to elevate the temperature of the first fluid flow from the first temperature to the second temperature.

An air pressure regulating device comprises an expansion tank having air stored therein and having an air injection/discharge port at an outside thereof; and a pressure regulation unit provided with a three-way ball valve connected to the air injection/discharge port, a pressure gauge which is installed in any one of flow paths of the three-way ball valve to check an internal pressure of the expansion tank, and a valve core which is installed in a flow path other than the flow path in which the pressure gauge is installed to be capable of injecting or discharging air into or from the expansion tank so as to be capable of controlling the internal pressure of the expansion tank.

A residential and commercial hot water and steam boiler safety system and device that includes at least one hollow pipe, with one plugged or sealed end and a fitting on the other end for connecting the pipe in a substantially vertical mounting position, and at least one two float switch disposed in the pipe and electrically connected in series with a limit switch in the boiler, where the pipe is adopted for the flow and accumulation of water, so that float switch activates as the pipe fills with water and shuts off the boiler by turning off the gas valve, promoting safer boiler and steam boiler operation. Additional float switches positioned above or below in the hollow pipe may provide additional functions, such as a warning light and sound to the owner, or a notification via a telephone or cell phone system or through the home network or Wi-Fi system.

A residential and commercial hot water and steam boiler safety system and device that includes at least one hollow pipe, with one plugged or sealed end and a fitting on the other end for connecting the pipe in a substantially vertical mounting position, and at least one two float switch disposed in the pipe and electrically connected in series with a limit switch in the boiler, where the pipe is adopted for the flow and accumulation of water, so that float switch activates as the pipe fills with water and shuts off the boiler by turning off the gas valve, promoting safer boiler and steam boiler operation. Additional float switches positioned above or below in the hollow pipe may provide additional functions, such as a warning light and sound to the owner, or a notification via a telephone or cell phone system or through the home network or Wi-Fi system.

A heat-pump air-conditioning hot-water supply device includes a first refrigerant passage connecting a compressor and a decompressor, a second refrigerant passage branching from between the compressor and a first solenoid valve and connecting a second solenoid valve, a hot-water supply heat exchanger, and the decompressor, a pressure sensor configured to measure discharge pressure of the compressor, and a control device configured to adjust an operational frequency of the compressor and adjust an opening degree of a valve of the decompressor. The control device is configured to calculate a condensing temperature from the discharge pressure, and perform operation in one of an air conditioning prioritized mode in which a preset operational frequency of the compressor is changed, and an energy saving prioritized mode in which the opening degree of the valve of the decompressor is changed, when the condensing temperature is not lower than a set condensing temperature.

A residential and commercial hot water and steam boiler safety system and device that includes at least one hollow pipe, with one plugged or sealed end and a fitting on the other end for connecting the pipe in a substantially vertical mounting position, and at least one two float switch disposed in the pipe and electrically connected in series with a limit switch in the boiler, where the pipe is adopted for the flow and accumulation of water, so that float switch activates as the pipe fills with water and shuts off the boiler by turning off the gas valve, promoting safer boiler and steam boiler operation. Additional float switches positioned above or below in the hollow pipe may provide additional functions, such as a warning light and sound to the owner, or a notification via a telephone or cell phone system or through the home network or Wi-Fi system.

Provided is an air pressure regulating device comprising an expansion tank having air stored therein and having an air injection/discharge port at an outside thereof; and a pressure regulation unit provided with a three-way ball valve connected to the air injection/discharge port, a pressure gauge which is installed in any one of flow paths of the three-way ball valve to check an internal pressure of the expansion tank, and a valve core which is installed in a flow path other than the flow path in which the pressure gauge is installed to be capable of injecting or discharging air into or from the expansion tank so as to be capable of controlling the internal pressure of the expansion tank.