Graham Hendra of LG Air Conditioning looks at the progress of VRF in comfort cooling and at the possible wider uses and flexibility of VRF. He also suggests that contractors and consultants take in the whole picture before deciding on their chosen product.
WHEN VRF systems first entered the air conditioning market all those years ago the smart money said the technology would never take off.

At that time chilled water and VAV systems were the order of the day and there appeared to be no room for these new systems.

How times change -and change quickly!

Early VRF systems almost exclusively used R22 refrigerant and had fairly tight restrictions on the number of units connectable. Typically it was eight and pipe lengths were normally limited to 100 meters.

Who would have predicted that by 2006 the VRF sector would have a powerful hold in the comfort air conditioning market, with sales estimated at around £110million a year and a projection of sales increases this year of 10% to15%?

It's not only the market share of these systems which has been accelerating - the technology packed into these machines has been evolving incredibly fast, as well.

It is now commonplace to be able to purchase VRF systems which can run 40 fan coils with a total capacity of more than 100kW connecting to 150 meters of pipe work.



Most of these systems now use DC, digitally commutated inverter compressors, and fan motors and the highly efficient R410A refrigerant which offers large capacities through tiny pipe work reducing the impact on riser space.

Modern inverters are no longer a high cost item and have none of the electrical noise or harmonic problems of their predecessors plus they offer motor efficiencies people only dreamt of 10 years ago.

With the introduction of Part L of the Building Regulations the drive for end users and specifiers towards energy efficiency is forcing contractors and consultants to look for highly efficient air-conditioning solutions.

There is now such a multitude of products available that VRF comes on the radar of virtually every possible commercial site.

There are multi-flexible systems which can do anything, anywhere, anytime - and give back valuable information to the building owner. There are systems that offer cooling only, heat pump and heat recovery solutions for every application - all in one unit.

These units can be connected to all sorts and types of indoor units. These systems have been designed with everybody in mind, especially for the designer who can use the freely available LATS software so that a complete VRF project can be sized and selected in a few minutes.

Once complete the pipe and wiring diagram can be drawn and printed out on to a CAD drawing in a matter of a few minutes.

For the contractor these systems now offer the ease of installation commonly associated with small split systems and the flexibility of larger water-based systems.

For the commissioning engineer the procedure couldn't be simpler with automatic system addressing and a wiring check that's almost impossible to make mistakes.

Collecting the commissioning data is simple too. It uses a normal Windows PC.



With a copy of service software the engineer can interrogate the system without leaving the roof.

The software allows him to see a detailed colour refrigeration flow diagram detailing each part of the system so problems can be easily identified.

For the end user there is a suite of controls solutions from full LON compatibility, PC based BMS solutions and wireless central control through to simple room controllers and touch screen remote controller.

Using a stand-alone energy monitoring system the end user can monitor the amount of energy used and the running cost of each unit allowing individual billing. With VRF anything is possible - you simply have to ask!