Comfortably controlled, low noise, draught-free with a proportion of filtered and ionised outside air is a must have in todays’ air-conditioned offices.

The Covid era has changed so many aspects of design previously taken for granted.

The 2021 office eclipses the standards of yesteryear, when simply recirculating heated and cooled air was the norm.

What hasn’t changed are the refrigerant and refrigerant/water-based designs. All will now be heat pumps able to cool and heat controlled and monitored from the office or from central building control.

Every person in a new office now requires a minimum ten litres per second of outside air. This may be delivered into the air stream to mix with some re-circulated air. Use of a heat exchanger will save energy by pre-heating or pre-cooling the outside air entering or leaving, it may also provide a positive or over-pressure to the room.

For accuracy in the selection of the air-conditioning system, knowledge of heat gains in the office is a necessity. So many installations are oversized in the absence of a thorough heat gain study. These are the systems that will never operate at full capacity and rely on speed-controlled fans and compressors to compensate for their selection error. Energy is their waste product.

Businesses will naturally investigate both the proportions of outside air provided for the office. They may consider filtering particles at PM 2.5 microns and ionising the airstream to destroy bacteria and viruses. – however, ultimately the efficiency of all air-conditioning rests with considerate system design.