Split heat pump

A split heat pump consists of an outdoor and an indoor unit connected by refrigerant lines. Installation requires specialist knowledge of refrigeration technology.

With a split heat pump, the device is split into two parts. According to Energieberatung NÖ (Energy Advisory Service Lower Austria), the evaporator and fan are located in the outdoor unit, while the condenser, circulation pump and control system are in the indoor unit. Both are connected via pipes in which the refrigerant flows.

Advantages

• The outdoor unit can be more compact because part of the technology is inside the house.
• There are no water pipes between the outdoor and indoor units that could freeze in winter.

Disadvantages

• According to Energieberatung NÖ (Energy Advisory Service Lower Austria), the connecting pipes filled with refrigerant require special expertise in refrigeration technology during installation. The refrigerant circuit is only closed on site.
• The refrigerant enters the house. For flammable refrigerants such as propane, the requirements for indoor installation are therefore higher.

Legal framework

EU Regulation 2024/573 specifically regulates split systems:

• Air-to-water split systems up to 12 kW: from 1 January 2027, no fluorinated gases with a GWP of 150 or more.
• Split systems up to 12 kW in general: from 1 January 2035, no more fluorinated gases.

Both bans apply with exceptions for safety requirements at the location. These are bans on placing products on the market, so they affect new devices and not the operation of systems that have already been installed.

Ask about the design and refrigerant in your quote. You can find the comparison under Monobloc.

All terms · Heat pump knowledge