Hot water – a source of wellbeing

Decentralised DHW heating

Solutions for efficient DHW heating can be divided into centralised and decentralised concepts. With centralised DHW heating, reasonable efficiency levels frequently dissipate as a result of long supply lines. This disadvantage is systematic. When it comes to CO2 emissions, a comparison is also worth the effort. Here too, decentralised DHW heating fares much better than is generally assumed.

Frequently, the real level of energy efficiency only becomes apparent at the end of the year,
as that is when many of the cost factors, such as the DHW circulation pump used in centralised systems, appear in the annual summary of charges. These are seldom marked down as DHW costs. By taking into account these hidden costs, electric DHW heating systems often turn out to be better than centralised oil or gas systems. Decentralised electric DHW systems, in particular, offer even more benefits – they are practically maintenance free and enable you to make simple, consumption-based cost calculations.

Following their adoption by the European Union (EU), the new Ecodesign Directive and new Energy Label must be implemented by all manufacturers of water heaters and DHW cylinders since September 2015. The statutory regulation for energy related products – also known as ErP – rates different appliances and categorises them into various efficiency classes. Aside from the efficiency classes, the individual load profiles should also be considered. The  labels with which we are already familiar on refrigerators, televisions and washing machines will also be used for domestic hot water appliances. Consequently, instantaneous water heaters, small water heaters, wall mounted cylinders, DHW heat pumps, solar cylinders and indirect water heaters will be furnished with a standard European Energy Label. This will be based on environmental consumer information such as energy consumption per year and whether the appliance qualifies for a low tariff.

The top of the ErP label displays the name of the manufacturer (I) and the model designation (II) of the product. The rating system for DHW appliances categorises them into seven efficiency classes. "A" is the highest energy efficiency class here. STIEBEL ELTRON products are almost exclusively in the top group. For example, our instantaneous water heaters and small water heaters will achieve the highest possible rating, which is efficiency class A.

Specific details for instantaneous water heaters and cylinders