A tempered hot water delivery system configured to prevent or reduce colonisation of Legionella bacteria in tempered water delivered from the system to one or more outlets in a facility. The system comprises: a thermostatic mixing valve comprising; a hot water inlet for connection to a supply of hot water at a temperature of at least 60 C., a cold water inlet for connection to a supply of cold water, a tempered water outlet for supplying tempered water obtained from mixing the supplied hot water and cold water to provide tempered water at a temperature of between 36 C. to about 53 C. to at least one tempered water outlet of a facility, a recirculating inlet for connection to a recirculating water line circuit; and a recirculating water line circuit comprising a circulating return line connected to a circulating return outlet from the facility and to a water inlet feed line for connection to an inlet of a water heater and storage tank for providing the supply of hot water, the recirculating water line circuit further comprising a thermostatic element configured to introduce hot water to the recirculating water line circuit to maintain the temperature of water in the recirculating water line circuit during periods of little or no draw-off.

A water heater includes a heat exchanger. A controllable three-way proportional valve provides a proportionally controllable flow to the hot water inlet of the heat exchanger and a boiler return water outlet. A mixing tank mixes a cold water and a hot water. The mixing tank provides a time delayed mixed water. A temperature sensor is disposed in or on the mixing tank to measure a temperature of the time delayed mixed water to provide a time delayed mixed water temperature. A feedforward control process running on a processor adjusts a proportional operating position of the controllable three-way proportional valve to regulate a temperature of hot water at the hx domestic hot water outlet based on the temperature of the time delayed mixed water temperature. A method for controlling a hot water temperature of a water heater a water heater using a flowmeter based feedforward control are also described.

Provided is a heat medium circulation device with a simple structure, capable of reducing power consumption in performing an anti-freezing treatment. A first heat medium circuit 2 and a second heat medium circuit 3 are connected via a connector 5. An anti-freezing control unit 42 activates the first pump 22 with the second pump 32 in a stopped state, when preventing the heat medium in the first heat medium circuit 2 from freezing.

A water heater appliance includes an electronic mixing valve configured for adjusting a ratio of cold water from a cold water inlet conduit to hot water from a hot water outlet conduit at a mixed water outlet of the electronic mixing valve. A flow meter is mounted to the mixed water outlet conduit or the cold water inlet conduit. A controller is configured to calculate a flow rate of hot water through the hot water outlet conduit based on a temperature measurement from each of a mixed water temperature sensor, a cold water temperature sensor and a hot water temperature sensor and a flow rate measurement from the flow meter.

A water heater appliance includes an electronic mixing valve configured for adjusting a ratio of cold water from a cold water inlet conduit to hot water from a hot water outlet conduit at a mixed water outlet of the electronic mixing valve. A cold water bypass conduit extends between the cold water inlet conduit and the mixed water outlet conduit. A cold water bypass valve is on the cold water bypass conduit. A controller is configured to close the cold water bypass valve when a temperature measurement from a mixed water temperature sensor is less than a threshold temperature.

A water heater appliance includes an electronic mixing valve configured for adjusting a ratio of cold water from a cold water inlet conduit to hot water from a hot water outlet conduit at a mixed water outlet of the electronic mixing valve. A cold water bypass conduit extends between the cold water inlet conduit and the mixed water outlet conduit. A cold water bypass valve is on the cold water bypass conduit. A controller is configured to close the cold water bypass valve when a temperature measurement from a mixed water temperature sensor is less than a threshold temperature.

A hydraulic separator for hydronic systems for heating and/or cooling, including a hollow body with a casing, internally defining a chamber; at least two first through openings for the delivery of a fluid, and at least two second through openings for the return of the fluid, said first openings and said second openings being made on said casing of the body and being suitable to put in fluid communication said chamber to external circuits by hydraulic connecting means, further includes at least a mobile element suitable for separating said chamber of the body in a first portion and a second portion, in such a way to reduce the opening section of passage and of fluid contact between said first portion and said second portion. The invention further includes a control method tor the hydraulic separator and hydronic systems for heating and/or cooling.