A combination boiler provides heated water to a boiler loop and heated domestic hot water (DHW) to a DHW loop. A primary heat exchanger is connected to the boiler loop. A burner provides heat to the primary heat exchanger and an input fan supplies a fuel and air mixture to the burner. A secondary heat exchanger transfers heat energy from the boiler loop to a domestic water loop. A controller determines a boiler loop flow rate. The controller measures an input temperature of the boiler loop, an output temperature of the boiler loop, and a DHW output temperature of the domestic water loop. The controller determines a DHW input temperature and estimates a DHW flow rate. The input fan speed is initiated or operated according to a required heat output of the burner corresponding to the DHW flow rate.

A hybrid multi-air conditioning system and a method for controlling a hybrid multi-air conditioning system are provided. The hybrid multi-air conditioning system may include a hot water supply unit including a hot water supply heat exchanger that exchanges heat between refrigerant and water accommodated in a water tank and a first hot water supply expansion valve that blocks or allows refrigerant condensed in the hot water supply heat exchanger to flow through a first hot water supply discharge pipe; at least one indoor device installed indoors and including an indoor heat exchanger and at least one indoor expansion valve; an outdoor device connected to the at least one indoor device and the hot water supply unit through a refrigerant pipe and including an outdoor heat exchanger, a compressor, and an outdoor expansion valve; a second hot water supply discharge pipe having a first side branched from the first hot water supply discharge pipe, which connects the hot water supply heat exchanger and the indoor heat exchanger, and a second side that joins a first discharge pipe, which connects the compressor and the outdoor heat exchanger; and a second hot water supply expansion valve installed on the second hot water supply discharge pipe.

The present disclosure relates to a heating, ventilation, and/or air conditioning (HVAC) system including a heating coil and an actuation system configured to couple to the heating coil. The actuation system is configured to rotatably position the heating coil in a first orientation crosswise to an airflow path in a heating mode, and rotatably position the heating coil in a second orientation substantially removed from the airflow path in a cooling mode.

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 heat exchanger includes a heat-transfer-tube unit and a header. The heat-transfer-tube unit includes a fin and heat transfer tubes. The header is connected to the heat-transfer-tube unit. The fin and the heat transfer tubes are disposed, alternately, side by side, where the heat transfer tubes extend in a heat-transfer-tube-extending direction. The fin has sides that extend in the heat-transfer-tube-extending direction and that are joined to the heat transfer tubes. An end of the fin is disposed closer to a center of the heat-transfer-tube unit in the heat-transfer-tube-extending direction than ends of the heat transfer tubes, and the ends of the heat transfer tubes are inserted into holes disposed on the header.

The present disclosure relates to combined heat and power plants. The teachings thereof may be embodied in methods for operating such a plant to provide electrical and thermal energy to a consumer unit, comprising: simultaneously generating electrical energy and heat in a process flow based on a demand for electricity; storing heat generated in excess of a demand for heat; and increasing a heat output when a difference between an actual provided heat output and the demand for heat is exceeded.

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.

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 system includes: a heat generator obtaining heat from a heat source and having a generator outlet port and a generator return port; a central heating circuit having a heating feed port and a heating return port; a tank having a top portion and a bottom portion, the tank containing a heat storing medium; a first tapping coil immersed in the heat storing medium in the bottom portion of the tank; and a second tapping coil immersed in the heat storing medium in the top portion of the tank The heat generator, second tapping coil, central heating circuit, and first tapping coil are fluidly connected in series to allow fluid to flow from the heat generator via at least one of the second tapping coil, the central heating circuit, and the first tapping coil back to the heat generator The system includes first, second and third three-way valves.

Heat and cold supply subatmospheric system for air conditioning refers to the area of heat power engineering, namely energy-saving technologies and is designed for autonomous heating, hot water supply and cold supply of residential, public and industrial buildings. To implement effective heat supply, a vacuum-steam method of heat transfer by steam with a controlled depth of pressure drop is used, heat supply subsystem efficiency reaches 0.9. Cooling supply subsystem, which is integrated with the heat supply subsystem, includes: installation of a non-absorbed absorption water cooling refrigeration machine and a system of air coolers of indirect evaporative cooling in a vacuum environment, while ensuring energy efficiency with an EER of 12.5 kWt/kWt.