ReChill® Scores Triple Top for Chiller Engineering

The Environmental Troika - Refrigerants phase out Energy Reduction Recycling by re-use.

For medium to large commercial buildings the water chillers providing the cooling services for the air-conditioning systems often represent the highest single energy load on the building.

Often they are cited as the heart of all evils within a building - expensive to maintain, unreliable, expensive to replace.

Until recently designers gave little thought to energy efficiency, the machines used HCFC refrigerant gases found to be harmful to the Ozone Layer, with the replacement HFC refrigerants are now deemed equally damaging due to adverse effects on Global Warming. They also require many tonnes of mined materials to manufacture. Replacing chillers is also expensive and very inconvenient, and, in our view often hugely wasteful of the mineral resources used in their original manufacture. However, the techniques now available under the ReChill® concept for bespoke application to individual chillers of virtually any make and model now allow modernisation of these machines to reflect the very latest available production techniques...

Refrigerant Situation

Hydro Chloro Fluoro Carbons - HCFCs, and notably R22, will be banned from further use after Christmas, yet hard on the heels of the HCFC phase out comes a decision from the EU that their replacements, HydroFluoroCarbons - HFCs, are equally bad for the environment, due to their inherent high Global Warming Potential and these fluids will have a limited life span with the majority scheduled to be gone from service by 2030. This presents a significant dilemma for equipment users, especially those investing now in new chillers expected to serve at least 20 years - these EU decisions have already limited the lifespan to at best 15 years.

The replacement fluids so far developed to replace HFCs are either toxic or (mostly) inflammable, and their use in closed plant rooms is far from clear. Of these Ammonia has been in use in larger industrial equipment for decades, and HydroFluoroOlefins - HFOs are now in development. Even though the timetable has been set, commercially developed and proven refrigerants are not yet available. Certain gases are high on the first to go list, e.g. R404A (used extensively in Supermarkets to replace the notorious CFC R502), and already R134a is banned from use in new car model production.

However, it is apparent not many users realise that most air-conditioning system refrigerants contain a large proportion of R134a - R407C; R404A; all R22 replacements. But even refrigerants without R134a will be directly affected by HFC phase out, e.g. R410A. R404A is the first to be highlighted as a villain - it’s GWP is massive.

Energy costs are only going one way, and the ability of the National Grid to withstand an ever growing demand is now being sorely tested. In the peak of Summer the water chiller load on a city like London is vast, and becomes the largest capacity demand. The heat rejection is such that a vast hot well forms over the city, increasing the discomfort for all, and seemingly concentrating harmful polluting emissions from vehicle exhaust and industry. Much of this local warming is due to inefficient plant and poor control of buildings to keep the cooled air in, and keep the heat out in the first place.

So a score of say 50 - 60% in energy reduction in the Chiller can be achieved - we have seen direct savings at some sites, but for many sites reducing the energy input will see the chillers less active, gaining significant indirect energy savings from having to cool less anyway.


Recycling a large machine is expensive and in itself heavy on resource usage. The material has to be transported, dismantled, separated, then smelted, itself a massive energy user. Therefore by life extending a large water chiller each and every component re-used means one less component to manufacture from mined or expensively recycled resources.

ReChill® offers all this and is effective for chillers from 150 to over 2,000 kW. On some sites the achieved Energy Efficiency has improved from below 2 to above 5.5.

The aspect not mentioned is the cost. In this most significant area ReChill® again scores at least twice - direct costs compared with typical replacement will be ~50%. This excludes the often significant costs associated with building disturbance. For some sites we have seen overall project cost for chiller replacement fall below 25% from the ReChill® option.

So if you are interested in an 'As New Chiller', with modern features such as high EER, Inverter Driven Screw compressors and fans, modern high specification, reliable controls, remote accessibility and virtual servicing, then you should let us assess your current chiller pool.