A safety heat exchanger for combining a heat pump with a device of a drinking water supply facility for obtaining heat from drinking water. The heat exchanger includes a primary circulation loop (4) with drinking water, a secondary circulation loop (6) with antifreeze as a material that does not pose a health risk, and a tertiary circulation loop (7) with a coolant. The primary circulation loop (4) includes an inlet (3) connected to a drinking water supply facility and an outlet (5) with electrically controllable magnetic valves (16). The secondary circulation loop (6) and tertiary circulation loop (7) each have any dedicated difference pressure monitor (9, 18), which difference pressure monitors (9, 18) are controllably connected with the magnetic valves (16) such that when the difference pressure monitors (9, 18) detects a pressure difference in the secondary circulation loop (6) and/or in the tertiary circulation loop (7), the inlet (3) and the outlet (5) of the drinking water to the drinking water facility are closed, wherein the difference pressure monitor (9) of the secondary circulation loop (6) comprises an expansion vessel (11), a safety valve (12) and a manometer (13).