DS EN 13203-2:2006 Gas-Fired Domestic Appliances Producing Hot Water - Appliances Not Exceeding 70 Kw Heat Input And 300 L Water Storage Capacity - Part 2: Assessment Of Energy Consumption Pertains to gas-fired appliances producing domestic hot water. It also applies to both instantaneous and storage appliances; waters-heaters and combination boilers that have heat input not exceeding 7