A heating and hot water supply system is provided and includes at least a distribution unit, a hot water supply heat exchanger and a flow rate adjusting unit. The distribution unit adjusts a distribution ratio capable of handling operations including heating, hot water supply and simultaneous heating and hot water supply operations. When the hot water supply operation starts, first hot water supply control, which adjusting a temperature to a hot water supply set temperature by the flow rate adjusting unit, is performed. After supplying the hot water having the hot water supply set temperature according to the first hot water supply control is maintained for a reference time or longer, transition to second hot water supply control, which a tapping water temperature of the hot water supply heat exchanger is brought close to the hot water supply set temperature, and a mixing amount of clean water reduced, is performed.

A method for controlling an on-demand high volume capable fluid heating system that supplies a total heating power at a turndown ratio and a total flowrate of a fluid supply, the fluid heating system comprising a plurality of heat exchangers fluidly connected in parallel, each of the plurality of heat exchangers comprising: a fluid conductor, wherein each of the plurality of heat exchangers contributes to the total heating power and a portion of the total flowrate of the fluid supply through the fluid conductor; an inlet conductor configured to connect the fluid supply to the plurality of heat exchangers; an outlet conductor configured for receiving the fluid supply downstream of the plurality of heat exchangers; an auxiliary conductor connecting the inlet conductor at a first location and the outlet conductor, the auxiliary conductor comprising a modulating valve; and a pump disposed downstream from the first location on the inlet conductor.

A combination boiler provides heated water to a boiler loop and domestic hot water (DHW) to a domestic water loop. The combination boiler includes a primary heat exchanger (PHE) connected to the boiler loop and a burner to provide heat to the primary heat exchanger. A secondary heat exchanger (SHE) transfers heat energy from the boiler loop to the domestic water loop. A controller monitors a PHE inlet temperature and a DHW output temperature, obtains a pre-heat initialization temperature threshold and a pre-heat cancellation temperature threshold, and detects a low temperature condition. A pre-heat operation is initiated responsive to the low temperature condition by circulating heated water from the PHE to the SHE. The burner is selectively fired at least in part according to an outlet temperature of the PHE.

A system for heating water to improve safety and efficiency. The system may have normal operation measured in time. After a time of normal operation, a water temperature setpoint may be checked. If the setpoint is not at a certain level, normal operation may continue. If the setpoint is within the certain level, water temperature may be measured. If the water temperature is less than a desired level, one or more draws of water may be measured for a preset temperature drop. If the draws do not meet the temperature drop, a return to check the setpoint may be made. If the draws meet the temperature drop, the setpoint may be reduced and a time of normal operation may be measured to determine whether a burn cycle occurs within the time. If not, normal operation may continue; but if so, a return to check the setpoint may be made.

A combination boiler provides heated water to a boiler loop and domestic hot water (DHW) to a domestic water loop. The combination boiler includes a primary heat exchanger (PHE) connected to the boiler loop and a burner to provide heat to the primary heat exchanger. A secondary heat exchanger (SHE) transfers heat energy from the boiler loop to the domestic water loop. A controller monitors a PHE inlet temperature and a DHW output temperature, obtains a pre-heat initialization temperature threshold and a pre-heat cancellation temperature threshold, and detects a low temperature condition. A pre-heat operation is initiated responsive to the low temperature condition by circulating heated water from the PHE to the SHE. The burner is selectively fired at least in part according to an outlet temperature of the PHE.

A water tank management system that connects either to a hot water tank directly or to an electric panel connected to the tank. The system comprises at least two temperature sensors, each of which is attached on the surface of the hot water tank near respective heating elements. The system comprises a control box which includes a solid-state relay that modulates the flow of electrical power to the heating elements in order to lower the energy used by the tank. The modulation is controlled by a program stored in a memory in the control box or communicated to the control box via an external controller. The system optionally comprises a third temperature sensor placed outdoors to measure the ambient outdoor temperature. With this feature, the system can activate a program to reduce energy consumption when the outdoor ambient temperature is outside a critical temperature range.

A water heater can include a tank, an inlet line, and an outlet line, where the inlet line provides unheated water to the tank, and where the outlet line draws heated water from the tank for a hot water demand. The water heater can also include a heat pump disposed adjacent to a first portion of the tank, where the heat pump applies heat to transform the unheated water to heated water in the first portion of the tank. The water heater can further include a resistive heating element disposed within a second portion of the tank, where the resistive heating element further applies heat to transform the unheated water to heated water in the second portion of the tank.

In a heating and hot water supply device including a burning means, a first heat exchanger, a circulation passage for circulating a heating thermal medium, a circulation pump, a first bypass passage, a second heat exchanger for hot water supply, a hot water supply passage, a second bypass passage bypassing the second heat exchanger, a control unit, and an operating terminal, a distribution means is provided at a branching portion of the first bypass passage and is capable of adjusting its distribution ratio for heating, or hot water supply, or simultaneous heating/hot water supply, a display means of the operating terminal is capable of providing displays corresponding to various types of operation.

A modularized combined intelligent heat collector system, comprising a PTCR-xthm electric heating chip heat source main engine, a data control template, a constant-temperature and constant-pressure device and a variable-frequency pump; the variable-frequency pump and the PTCR-xthm electric heating chip heat source main engine are connected to the data control template; the outlet end of the PTCR-xthm electric heating chip heat source main engine is connected to the constant-temperature and constant-pressure device; the outlet end of the constant-temperature and constant-pressure device is connected to the PTCR-xthm electric heating chip heat source main engine through the variable-frequency pump; the PTCR-xthm electric heating chip heat source main engine directly leads out a user heating pipeline; and/or the PTCR-xthm electric heating chip heat source main engine leads out the user heating pipeline through the constant-temperature and constant-pressure device, and is connected to a heat exchanger of a user water heater.

The purpose of the present invention is to provide a hot water supplying apparatus which enables supply of hot water by utilizing waste heat of a pipe and a boiler as a heat source if there is a small quantity of residual hot water to use therefor, the residual hot water being required when using hot water of an instantaneous boiler, and a method for utilizing waste heat of a hot water supplying apparatus. The hot water supplying apparatus of the present invention for achieving said purpose comprises: a sensible heat exchanger for heating a heating fluid by means of combustion heat from a burner; a hot water supply heat exchanger for generating hot water by means of a heat exchange between the heating fluid heated by the sensible heat exchanger and direct water, and supplying the hot water to a faucet; and a pump for circulating the heating fluid via a heating fluid flow path which connects the sensible heat exchanger and the hot water supply heat exchanger, wherein the hot water supplying apparatus comprises: a signal reception unit for receiving a final hot water use signal; and a control unit for stopping the operation of the burner on the basis of the signal received by the signal reception unit and controlling the pump to circulate the heating fluid.