Provided is a hot water supply apparatus. Processing executed by the hot water supply apparatus includes the following. A hot water supply set temperature is read from a memory. A maximum temperature of a housing is set by combustion level (combustion stage number) in accordance with a setting pattern predetermined according to the hot water supply set temperature. When it is intended to detect an end of operation of the hot water supply apparatus in the case of detecting no change in the hot water supply set temperature, a combustion operation is continued. The maximum temperature of the housing is set again by combustion level (combustion stage number) in the case of detecting a change in the hot water supply set temperature.

A removal device for removing gas bubbles and/or dirt particles from a liquid in a liquid conduit system includes a housing having an entry and an exit and, a main ongoing flow channel which extends through the housing from the entry to the exit, a plurality of branch flow channels, each branch flow channel branching off from the main flow channel at a branch point, at least one quiet zone which is provided at the ends of the branch flow channels, at least one return flow channel for a return flow from the at least one quiet zone back to the main flow channel, where the return flow channel merges with the main flow channel at a merge point, and where the branch flow channels are defined by plates which are curved.

A controller performs a first operation in which a heat source device directly or indirectly heats water in a first channel of a heat exchanger and a second operation in which the heat source device directly or indirectly cools the water in the first channel of the heat exchanger after the first operation ends.

A tamper-proof fluid sediment trap including a central body portion having a central longitudinal axis, an outlet leg portion, a drip leg portion, and a supply leg portion. The outlet leg portion extends upward from the central body portion parallel to the central longitudinal axis and is configured to operably couple to an appliance. The drip leg portion extends downward from the central body portion and defines a shape being resistant to threading or tapping of an outer surface or an inner surface of the drip leg portion. The supply leg portion is configured to couple to a fluid supply line, extends radially outward from the central body portion, between the outlet leg portion and the drip leg portion, and has a central longitudinal axis extending perpendicular to the central longitudinal axis of the central body portion. The portions of the tamper-proof fluid sediment trap are monolithically formed.

A method controls a household appliance being or containing a water heater with regard to limescale deposition. The method includes generating at least one thermal pulse by operation of an electrical heating element of the water heater, and measuring a plurality of successive temperature values. The method further includes determining one or more parameter values of a measurement pattern arising from the plurality of successive temperature values and their respective time of measurement, and ascertaining a limescale deposition state of the water heater based on the determined parameter value. A household appliance contains a computer readable medium having stored thereon instructions configured to trigger, when executed, the household appliance to perform such a method.

An automated descaling system can be integrated into a tankless water heater or can be a separate system that is connected to a tankless water heater. The automatic descaling system comprises a cleaning media chamber and a valve with a motor. The descaling system can be set on an automatic cleaning schedule.

A water decalcification system includes an electroactive polymer (EAP) layer having at least one EAP film, a first electrode contacting the EAP layer and configured to contact a surface of an appliance capable of having at least one interior surface with limescales built up thereon, a second electrode contacting the EAP layer, and an electrical connector configured to connect to an electrical source in electrical communication with the first and the second electrode and configured to apply an electrical voltage to the first and the second electrode. The at least one EAP film deforms in response to the electrical voltage to generate ultrasound vibrational energies transmissive to decalcify the limescales.

There is provided a system and method of selectively monitoring ions in a fluid medium using a graphene sensor, the method comprising the step of adjusting an operating frequency of the graphene sensor to a particular resonant frequency for targeting resonance of specific ions in the fluid medium. In the proposed method, dispersive effect of the fluid medium is used to tune the graphene sensor to a desired frequency, thereby obtaining resonance response for specific ions in the fluid medium. Also, the monitoring of a specific ion in the fluid medium is unaffected by presence of a plurality of other ions in the said fluid medium.

A hot water supply device including an inlet pipe, an outlet pipe, a burner unit, a heat exchanger, an exhaust aperture, a first temperature sensor detecting a measured exhaust temperature of the exhaust gas, a second temperature sensor detecting a water temperature of water entering the inlet pipe, and a processor. The processor is configured to obtain an error between the measured exhaust temperature and an estimated exhaust temperature, and detects that scale clogging has occurred inside the heat exchange tubing based on an index which is generated using the error between the measured exhaust temperature and the estimated exhaust temperature. The estimated exhaust temperature is a first predetermined value that is determined using a numerical equation which has at least the water temperature of water entering the inlet pipe and a scale number of the hot water supply device as variables of the numerical equation.

A water heating and treatment system includes a water heater, a hot water outflow line from the water heater, and a cold water supply line to supply water to the water heater. The cold water supply line includes at least one of an anti-scale device, and a UV sanitation lamp. A mixing station supplies a temperature regulated heated water to one or multiple temperature zones. A mixing station supplies heated water to at least a first temperature zone at a first hot water temperature. The water heater, the anti-scale device, the UV sanitation lamp and the mixing station are contained in a single enclosure having at least one sliding transparent wall through which components can be viewed. A plurality of pipe connections passing through a rear panel of said single enclosure are also described.