Are VRF/VRV air conditioning systems the right choice for the future?
The decarbonisation and electrification of buildings has become a key focus within the real estate industry – choosing the right air conditioning system can play a central part in this mission.
Variable Refrigerant Flow (VRF) and Variable Refrigerant Volume (VRV) air conditioning systems were once considered a lower cost option for heating and cooling buildings, while also reducing operational carbon emissions. However, with evolving regulations, their long term viability is being questioned.
Centralised heating and cooling heat pumps, utilising closed water pipe networks, are emerging as a compelling alternative to traditional VRF and VRV. These water-based systems are expected to offer greater cost effectiveness over their lifespan and align more favourably with regulatory frameworks.
Additionally, their reduced whole life carbon impact is likely to appeal to businesses striving to meet Scope 1 and 3 carbon emission targets. For buildings with ageing VRF/VRV or those planning retrofits, early preparation is essential.
Environmental impact and regulation
VRF and VRV systems use refrigerant gases distributed throughout a building, which can be harmful to the environment and health if they leak. With stricter regulations targeting climate damaging refrigerants, their future faces challenges. The UK is expected to update its F-gas regulations this year, following the EU, to phase out environmentally harmful refrigerants by 2050.
To address the regulations, manufacturers have moved to using lower Global Warming Potential (GWP) R32 refrigerant as it has a lower GWP than traditional HFC refrigerants such as R410a. However, R32 is a temporary solution, and is subject to a phase down from 2027 for split/DX systems (an air conditioning system that places the compressor and condenser outside the building, while the evaporator and fans are inside) and a phase out between 2030 and 2040 for larger VRF/VRV systems under existing F-gas regulations.
R410a refrigerant is banned for new small split and DX systems and large VRF/VRV systems using R410a are anticipated to be banned for new installations in 2029 due to their negative environmental impact. While compliant in the short-term, these will therefore see rising maintenance and retrofit costs over their 15-year lifespan, and the phase out in the medium to long-term may impact asset value.
Exploring alternative refrigerant options
Manufacturers face challenges in developing VRF/VRV systems with future proof refrigerant in building applications. Carbon dioxide (CO2) is a low GWP option but has issues like limited system capacity, leakage safety risks, lower energy efficiency, and higher installation costs, making it less attractive compared to higher-GWP refrigerants. CO2-based VRF/VRV systems require higher operating pressures, posing asphyxiation risks from leaks. Additional safety measures like gas monitoring, alarms, and venting are needed.
Shifting towards water-based systems
Water-based techniques are future proof, offering long lifespans, net zero compliance and reduced refrigerant gas volumes. Upcoming district heating regulations in England may require certain buildings to connect to new or existing networks and prohibit VRF/VRV systems in designated zones.
It is not recommended to replace current water-based systems with VRF systems in order to lower embodied carbon emissions, mitigate risks associated with F-gas regulations, and prevent potential increases in maintenance costs and depreciation of asset value.
Water-based systems can be maintained or adapted to align with Net Zero targets by transitioning to high-efficiency electric central plant technology. This enables building-wide heat recovery and typically ensures infrastructure longevity of over 40 years. Moreover, it has the potential to reduce external plant area requirements and peak power demands, providing a more sustainable and adaptable solution for achieving Net Zero targets while reducing long term costs and risks. VRF/VRV solutions may become a thing of the past for conventional applications due to short term regulation changes.
Article credit from Savills
Matthew King
Design Director, Engineering & Design Consultancy
+44 (0) 7811 783878