The “micro storage water heaters” are adapted to basins, sinks and showers where the distance between the boiler and the draw-off point is too important. They avoid wasting cold water contained in the circuit until hot water arrives to the draw point.
If your heating system can be independent of your domestic hot water (DHW) production circuit, this solution might be interesting from an energetic point of view as only very small amount of water is heated.
The water heating temperature is between 50°C to 60°C for sanitary hygiene reasons. It is reduced by the addition of cold water at the tap. It is usually not adjustable. Run the water heater during off-peak hours to limit your consumption (off-peak hours or day/night switch and an adapted subscription).
If you are in a limestone area, think of a steatite resistant water heater (protected by a sheath), or a titanium/magnesium anode, in order to avoid limescale building-up and therefore the reduction in efficiency.
Simple installation to carry out according to the standards
The hot water production electrical circuit is protected according to its power, generally, by a 20A circuit breaker, a differential device of 30 mA and power cables of 2.5 mm2. The standards require grounding all metal (copper) hydraulic distribution sections.
Provide space related to the security unit to associate with the water heater. This serves to protect the tank from the water heater against pressure excess and prevents any hot water return into the cold water circuit. The security unit drain port is to be connected to a drainage via a siphon kit.
Price ranges for quality products are between £200 to £500 for one 30 litres tank.
Choose a model with vertical or horizontal installation depending on your configuration.