prEN 15502-2-3-2021 Gas-fired central heating boilers - Part 2-3: Specific standard for hybrid space heating appliances combining a gas fired appliances and heat pump in a product
2021prEN 15502-2-3-2021 Gas-fired central heating boilers - Part 2-3: Specific standard for hybrid space heating appliances combining a gas fired appliances and heat pump in a product