Combination thermal store with DHW heating in a stainless-steel heat exchanger. The tank is suitable for storing and subsequent distribution of thermal energy from heat pumps. A hydronic fireplace insert or another boiler can be also connected. Heat sources can be combined. The tank can accommodate 2 el. heating elements for space heating and another heating element for DHW heating. The tank also permits installation of an electric heating element for utilization of surplus electricity from PV sources in the entire tank volume.