The ultimate guide to Hybrid air conditioning

The ultimate guide to Hybrid air conditioning

Jobin Varghese from Mitsubishi Electric focuses on a unique water-based VRF solution

If you know anything about air conditioning then you will know that today’s modern buildings are highly likely to use what is known as VRF systems, which refers to the Variable Refrigerant Flow (VRF) that the equipment utilises to transfer heating and cooling around a room, a space, or an entire building.

VRF systems have become incredibly popular because they provide market-leading levels of efficiency that help reduce running costs. In addition, flexibility in design and the ability to fit units in a modular fashion reduces installation costs. Overall, Hybrid VRF offers convenience as it comes as a complete package solution, from the stylish choice of indoor units to a complete controls package.

Our market leading VRF is the City Multi range, which is a direct expansion type air conditioning system where one outdoor unit is connected with multiple indoor units.

The system intelligently modulates the flow of refrigerant depending upon the capacity for heating or cooling requirements in each zone within a building.

Its ultimate purpose is to regulate the internal room air temperature and comfort levels effectively and efficiently.

We believe there is no limitation with Hybrid VRF and the possibilities are endless

One or both

Constant development and innovation mean that City Multi VRF can be applied as both Heat Recovery and Heat Pump systems.

Heat Recovery Systems

Heat recovery systems provide simultaneous heating and cooling with the benefit of heat recovery. By moving energy where it’s needed, power input is reduced by up to 30%, offering flexibility, operability, comfort and control. These systems are ideal for hotels, offices, and leisure facilities where there are different heating and cooling requirements throughout the building.

Heat Pump Systems

One outdoor unit provides all indoor units heating or cooling at a given time, making this system ideal for open plan offices, call centres or retail units.

So, what is HYBRID VRF?

There are situations though, where you may not want refrigerant piping in parts of a building, and this is where Hybrid VRF comes into it’s own.

Hybrid VRF, or otherwise knowns as HVRF, is an innovative air conditioning system unique to Mitsubishi Electric, whereby the outdoor unit is connected with a 2-pipe heat recovery VRF system, and water is used between the Hybrid Branch Controller (HBC) and indoor units – instead of refrigerant.

With water pipework connecting the indoor units, Hybrid VRF provides comfortable and stable air temperature control with no refrigerant in occupied spaces, meaning simple compliance with BS EN378 and removing the need for expensive leak detection.

Where can HVRF be applied?

Buildings around the UK have a high priority when it comes to energy efficiency, internal comfort and an easy control solution. We believe there is no limitation with Hybrid VRF and the possibilities are endless.


Customer comfort is paramount with legislation focusing attention on energy use and seeking to limit the use of refrigerant in occupied spaces. Hybrid VRF removes the need for leak detection thereby reducing the total cost of the system and on-going maintenance of the leak detection systems itself.

Office Buildings

Modern offices and commercial buildings need air conditioning systems that provide the highest levels of comfort and freshness, as energy efficiently as possible. Furthermore an office can simply be transformed from a CAT A to a CAT B fit out as water pipes can easily be isolated from the Hybrid Branch Controller box making building layout changes simple.

Hospital & Medical Centres

With regards to patient’s health and safety, this system has no refrigerant in the indoor units and at the same time it can deliver mild off-coil temperatures through the water-based Hybrid VRF indoor units.

Educational buildings

Providing comfort through temperature stability, removal of refrigerant from the occupied space and reduced noise – Hybrid VRF provides a truly integrated solution.

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