This heat pump installation in a new-build home dating from the beginning of the millennium shows that, when properly designed, a heat pump can provide reliable service for many years.

In this particular case, it is a split air-to-water heat pump in the Aku version, with an integrated 170-litre domestic hot water (DHW) tank.

• The AirMaster 3030 Aku is designed for buildings with a heat loss of around 10 kW.

Thought through to the last detail

The outdoor unit features an older type of horizontally positioned evaporator and is therefore somewhat noisier by today's standards. However, the owner has surrounded it with thuja trees, which partially conceal the heat pump without restricting the airflow. This provides an elegant solution from both a visual and, to some extent, acoustic point of view. As the owner herself says, she has become used to the sound of the heat pump over the years – at least she knows that it is running and everything is working as it should.

The indoor unit is located in a dry pantry, where it has been protected from the weather and exposed to ideal conditions throughout its service life. As a result, the tank and all internal components remain in excellent condition even after more than two decades.

Replacement with an R290 monoblock is possible

Due to new European legislation, split units with a capacity of up to 12 kW using synthetic refrigerants will no longer be allowed to be placed on the market from 1 January 2027. The owner therefore wanted to make sure that the existing split system could eventually be replaced with a monoblock heat pump.

In general, such a replacement requires the existing refrigerant lines between the outdoor and indoor units to be replaced. With a monoblock heat pump, the heating water itself flows through the pipes between the outdoor unit and the building. New heat pumps using the natural refrigerant R290 also require certain safety distances to be maintained, for example from windows and doors.

In this case, however, a future replacement should not present any major difficulties. The paving can be easily removed, making the necessary groundworks and pipe replacement straightforward. The existing location among the thuja trees can also be retained for a new monoblock heat pump.

Still going strong

The current unit, however, is still in good condition. A newer model would offer quieter operation, higher efficiency and more advanced controls, but why replace something that continues to work reliably? So, for now, one of our record-breakers can keep adding more years to its impressive service life.