Variable Refrigerant Volume Systems

The variable refrigerant volume systems (VRV/VRF) is basically a large multiple split system. The system can comprise of several indoor fan coil units, matched to one or more outdoor condensing units.

The VRV / VRF systems can achieve high efficiencies through heat recovery and accurate temperature control. This is achieved with the use of inverters and electronic controls. The systems are split into two basic forms...

Two pipe heat pump systems

The two pipe inverter VRV / VRF system is very similar to the multi system explained in the split system section. The system will consist of several indoor units that can be of different types and sizes. The indoor units are served by one or more outdoor condensing units, all using one common refrigerant pipe work system.two pipe vrf system

The two pipe system can only run in one mode of operation, heating or cooling. This means that all units can only control when in the same mode. However, the system does allow the individual setting of each fan coil unit within the selected mode.

The two pipe heat pump VRV / VRF system is suitable for large open plan areas, or areas that only require to be within the same mode at once (heating or cooling). The use of inverters within the outdoor condensing unit allows the system to perform only the required amount of heating or cooling, thus saving energy all round...

Three pipe heat recovery systems

The three pipe VRF heat recovery system is similar in configuration to the two pipe system above. Multiple indoor units are connected to one or more outdoor units via one set of refrigeration pipe work. The three pipe system uses three separate pipes rather than two (as the name suggests) between all units connected.three pipe heat recovery vrf system

The three pipe system allows total individual control for each indoor unit. The indoor units can be set in individual modes in any combination. The system also has the ability to recover heat from one area and pass it to another or vice versa. This heat recovery process makes a very efficient system, if designed and installed correctly.

For example take a large busy office containing a large amount of computer equipment. The office requires cooling to make the area comfortable for the operators within. A three pipe system is installed to carry out the cooling requirements. The system also serves a number of smaller individual offices. The smaller offices require heating. The three pipe system now has the ability to pass the heat absorbed from the main office to the smaller offices as required, and vice versa. Thus the system recovers heat...

Gas powered VRV / VRF systems

Where the amount of electrical supply is limited and a gas supply is available, gas powered VRF systems can be used. The gas powered VRF system uses a gas powered internal combustion engine in place of the electric compressors in the standard systems.

VRF condensing unit with gas engine

The gas powered units have the advantage of reclaiming waste engine heat, when in the heating mode.

Units are also available that will heat hot water and generate electrical power at the same time. These systems have been installed where it is uneconomical to uprate the building electrical power supplies...


The systems can be purchased as heat pump, or heat recovery types described above. Heating or cooling outputs are varied by engine speed, similar to the inverter control of the standard systems.

The systems can also now have the ability to provide additional services such as small power generation and domestic hot water...

Please take a moment to browse the site, if you need any further information then please contact us on: [email protected]