A fluid circulation type heating apparatus includes: a circulation line; a heat radiation member installed on the circulation line; a boiler configured to heat and expand a fluid; a storage tank configured to store the fluid and to supply the fluid to the boiler; a controller configured to control the boiler; and a housing configured to accommodate the boiler and the controller. The apparatus further includes: a backflow prevention means removably installed in the housing and configured to, when mounted to the housing, communicate with the circulation line disposed between the boiler and the storage tank, the backflow prevention means configured to allow the fluid to flow in one direction through the circulation line.

A heat exchanger having a drainage member (1) mounted on an open end (322) of a heat-transfer tube (32), wherein the drainage member (1) contains a flow guide portion (11) including an insertion portion (11a) configured to be inserted into the heat-transfer tube (32) from the open end (322), and a projecting portion (11b) projecting toward an outside of the heat-transfer tube (32) from the open end (322) and extending downward.

A hot water heater appliance includes a boiler, a companion water heater and a controller. The controller is configured to control the water heater appliance in response to a scheduled plurality of performance modes based on a preset schedule. A first performance mode is scheduled to be performed at an expected low usage time and a second performance mode is scheduled to be performed at an expected high usage time relative to the expected low usage time.

A hot water heater appliance includes a boiler, a companion water heater and a controller. The controller is configured to control the water heater appliance in response to a scheduled plurality of performance modes based on a preset schedule. A first performance mode is scheduled to be performed at an expected low usage time and a second performance mode is scheduled to be performed at an expected high usage time relative to the expected low usage time.

A waste heat recovery device with a first heat medium side inlet; a first heat medium side outlet; a first heat medium flow path; a second heat medium side inlet; a second heat medium side outlet; a second heat medium flow path; a heat exchanger that exchanges heat between the first heat medium and second heat medium; an expansion tank in the first heat medium flow path; a bypass flow path that causes the first heat medium to flow and bypass the heat exchanger; and a mixer where the bypass flow path and first heat medium flow path merge together. The mixer is configured to adjust a ratio of a flow rate of the first heat medium in the bypass flow path and a flow rate of the first heat medium in the heat exchanger, such that the temperature of the first heat medium after merging approaches a predetermined temperature.

A waste heat recovery device with a first heat medium side inlet; a first heat medium side outlet; a first heat medium flow path; a second heat medium side inlet; a second heat medium side outlet; a second heat medium flow path; a heat exchanger that exchanges heat between the first heat medium and second heat medium; an expansion tank in the first heat medium flow path; a bypass flow path that causes the first heat medium to flow and bypass the heat exchanger; and a mixer where the bypass flow path and first heat medium flow path merge together. The mixer is configured to adjust a ratio of a flow rate of the first heat medium in the bypass flow path and a flow rate of the first heat medium in the heat exchanger, such that the temperature of the first heat medium after merging approaches a predetermined temperature.

A dual energy gas water heater is described and wherein a square flange, curved resistor style resistive heating element, is secured in a bottom portion of the tank of the water heater spaced above a top wall of the combustion chamber. A gas burner is secured in the combustion chamber and connected to a gas supply line through a gas valve. The curved resistive heating element is a low density, long life, element having a density in the range of about 20 to 80 watts/sq. inches. A switch is secured between the thermostat of the resistive heating element and the voltage supply line. A controller selectively operates the switch and the gas valve to disconnect the voltage supply line from the thermostat and/or shut-off the gas valve secured to the gas supply line depending on the desired source of energy. The controller is adapted to be optionally controlled by a utility/provider through a communication link. Renewable energy source may also be secured to an additional resistive heating element to improve the efficiency thereof.

A smart boiler system serving boilers each equipped with sensor/s monitoring an aspect of boiler water heating functionality and a local controller collecting sensor data and communicating data to remote server, the system comprising a central server in data communication with said data network and including a processor having operational mode/s including a maintenance-needs-detection operational mode operative to scan data stored in a boiler data repository, on occasion, and to rank boilers accordingly, in terms of predetermined criterion defining maintenance need/s, and provide push output/s indicating a subset of boilers currently ranking high in terms of predetermined criterion defining at least one maintenance need.

A water heating system can include a first tank-based water heater having a first inlet line and a first outlet line, where the first inlet line provides unheated water to the first tank, and where the first outlet line draws heated water from the first tank. The system can also include a first tankless water heater having a second outlet line, where the second outlet line of the first tankless water heater provides the heated water to a first heated water demand. The system can also include a first valve that controls an amount of the unheated water flowing through the first inlet line to the first tank-based water heater. The system can further include a controller operatively coupled to the first valve, where the controller controls a position of the first valve based on the first heated water demand and a first capacity of the first tankless water heater.

A water heating system can include a first tank-based water heater having a first inlet line and a first outlet line, where the first inlet line provides unheated water to the first tank, and where the first outlet line draws heated water from the first tank. The system can also include a first tankless water heater having a second outlet line, where the second outlet line of the first tankless water heater provides the heated water to a first heated water demand. The system can also include a first valve that controls an amount of the unheated water flowing through the first inlet line to the first tank-based water heater. The system can further include a controller operatively coupled to the first valve, where the controller controls a position of the first valve based on the first heated water demand and a first capacity of the first tankless water heater.