Modern Building Services

FEATURE AIR CONDITIONING, COOLING & VENTILATION 12 MODERN BUILDING SERVICES MARCH 2023 Solutions In situations like this, when passive methods of ventilating away excess heat are not feasible, mechanical means must be considered. Approved Document O however, advises that mechanical cooling may only be used where insufficient heat is capable of being removed from the indoor environment without it, but Cooling often appears the only option for many buildings built in the UK. Airconditioning Centralised, plant providing, site- wide air conditioning could provide a solution to this risk. However, affected apartments represent only a percentage of the total development. And, often only on lower floors where pollution and security are the issue, or sides of a development adjacent to sources of noise. Which means, serving only part of the development with central plant cooling is just not cost effective. Demand on central systems is dependent on so many factors that it’s unlikely a central plant could ever operate efficiently. Splits Split systems with fan-coils could be used. However, the space will require unsightly external condensers unlikely to find favour with architects or planners. MVHR Mechanical ventilation systems with heat recovery (MVHR) can work to both pre-heat fresh air in winter and pre-cool the air being supplied into the property in summer as well as filtering pollutants from the air. AnMVHR can be pre-programmed to target a comfortable temperature, maximising free- cooling through its bypass when the external air is cooler than internal and coolth recovery when hotter external air can be cooled by extracted stale air from wet-rooms. The cooling module could activate automatically to lower supply air temperatures when required. Hybrid Then, as a last line of defence against overheating, there are hybrid cooling systems. Some of these new hybrid systems can integrate with the MVHR system and operate in conjunction with it. They have the potential to solve problem areas of developments by delivering cooled fresh air through the supply side of the MVHR system, when required, to combat rising external temperatures. The Hybrid Cooling system makes no claim to be comfort cooling or air-conditioning as it works purely by significantly lowering the temperature of the fresh-air supply in order to improve occupant comfort. It is time for a fresh look at how we tackle building overheating head on and create an optimal thermal temperature all year round providing a solution for specifiers that confidently meets building regulations. Source 1 https://tinyurl.com/3fd9pw2y More information can be found at www.nuaire.co.uk