The energy label for hot water storage appliances with a maximum rated thermal output of 70 kW and for water heaters with a maximum storage capacity of 500 litres was introduced in the EU in September 2015 and was declared mandatory in Switzerland on 1 August 2016.
With this label it is possible to readily check the efficiency of different types of water heaters and hot water storage appliances. It also defines the applicable energy requirements for the various appliances. In some cases Switzerland implements more stringent requirements than the EU.
The energy efficiency of water heaters and hot water storage appliances is to a large extent influenced by proper installation, and correct operation and maintenance.