A 3-in-1 system is a heat pump integrated with a storage cylinder and a reversible cooling circuit. One unit replaces a boiler, an air conditioner and a water heater.
Winter: the pump operates for house heating, simultaneously heating water in the cylinder via a three-way valve.
Summer: reverse mode turns the pump into an air conditioner. The heat extracted from the rooms partly goes to DHW heating — effectively, air conditioning happens with a useful side effect.
Year-round: the cylinder is always heated by the pump, not electric elements, giving a COP of 3.5–4.5 even in summer.
Such systems are ideal for new homes or major renovations where the design can be built around a heat pump from the start. Heating, cooling and hot water in one system are provided, for example, by the Termojet Suntide Premium Split.
