DHW systems can be basically divided into two main parts:
- the DHW heater where the DHW is heated from cold potable water, and
- the in‐house DHW distribution system, i.e., pipes connecting the heat.
Standards stipulate the following requirements for all DHW systems:
- Hygiene – DHW should be delivered without increased risk for bacterial growth.
- Comfort – DHW should be delivered in reasonable time, with the desired temperature and without unwanted fluctuations in temperature.
Standards stipulate that the DHW should be delivered to every DHW tap with a minimal temperature of 50°C, but the temperature can drop to 45°C during peak situations. However, it varies depending on the DHW use (tapping types).
TYPES OF WATER HEATERS:
- Conventional storage water heaters offer a ready reservoir (storage tank) of hot water
- Tankless or demand-type water heaters heat water directly without the use of a storage tank.
- Heat pump water heaters move heat from one place to another instead of generating heat directly for providing hot water.
- Solar water heaters use the sun’s heat to provide hot water.
- Tankless coil and indirect water heaters use a home’s space heating system to heat water.
