In recent years, health and wellness has become a top priority in nearly every facet of our lives, from nutrition to sleep and exercise. Yet a growing body of research demonstrates that health and wellness is not just about eating well and staying active; in fact, the environments where we live and work have a direct impact on our well-being, from our sleep/ wake cycles and mood to productivity and performance. Indeed, it is becoming increasingly important to place people at the heart of design and construction operations and development decisions. Danny Packham, European product Manager – Warm Air and radiant for Nortek Global HVAC UK Ltd, talks about planning a heating and ventilation strategy for the wellbeing of occupants.
What do we need to consider when planning a heating and ventilation system for the wellbeing of occupants;
1. Comfort of indoor environment
The importance of an HVAC system in commercial and residential buildings cannot be overemphasized, but is sometimes overlooked.
The fact remains that fresh air is good for the body, and in commercial buildings, it helps improve productivity. A good ventilation system helps to reduce the number of pollutants, bacteria and odour in a facility.
A number of different types of ventilation systems are available, ranging from a simple fan only system right up to a packaged heating, cooling and heat recovery system. However a good ventilation system will not only meet the ventilation requirements of the building but will also meet its temperature comfort conditions. This is where a mechanical ventilation has its advantages as it can be combined with a gas fired heating unit (condensing models offer thermal efficiencies of up to 109% – net CV) to meet the winter conditions. Free-cooling, will in most cases, help to lower the space temperature when it creeps above the desired set-point, and for when those summer time temperatures cause the mercury to rise even higher, a mechanical cooling system will be necessary to improve comfort conditions for the occupants.
Mechanical ventilation can meet the above and more besides, the more air changes within a space will help improve air quality as fresh air, or air from another source, is replacing the air within. The number of air changes per area varies depending upon the functions carried out.
All of these options can be combined into a single piece of HVAC equipment that can also include air to air heat recovery via a thermal wheel. These allow the recovery of otherwise wasted energy exhausted from the building to be re-used, to pre-heat fresh air entering the building. This in turn will help reduce the amount of energy used to meet the heating demand of the building.
The Reznor RTU range is composed of air to air heat pumps, packaged with various heat recovery options and gas fired heating coils to maximize efficiency. All units come equipped as standard with high efficiency G4 class air filters. Fresh air and ventilation options provide a high level of indoor air quality and help ensure a clean and comfortable conditioned space.
Control of your system is just as important as the HVAC system itself, a correctly selected system will maximize the performance, efficiency and comfort conditions within the building. All RTU’s are supplied with a Carel control system that’s provides fully automatic operation of cooling, ventilation, heating and heat recovery functions.
2. Energy efficiency
Operating a HVAC system at optimum efficiency is a challenging endeavour. The number of set points, levels and feedbacks of boilers, chillers, pumps, fans, air delivery components and more can cause costly inefficiencies. Add to that the fact that weather variables affect the heat transfers in a building and increase loads on the HVAC. Multiscroll technology combined with electronic expansion valves (EEV) and EC plug fans increase the system energy efficiency and provide a resilient and reliable solution.
Due to the RTU’s ability to produce its output in smaller increments, spaces with a variable occupancy rate and changing conditions during the day, such as shopping centres, can benefit from energy savings up to 30%.
3. Improve indoor air quality
According to the Environmental Protection Agency (EPA), poor indoor air quality is among the top factors of environmental risk. Pollutants in the air can aggravate allergies and asthma in some people and cause dizziness and headaches in others. Air quality depends on various factors. Too many people within a poorly ventilated space will cause an increase in poor air quality. Good levels of air filtration will help remove larger pollutant particles from the airstream and is necessary to maintain good levels of air quality.
Natural ventilation can improve indoor air quality by reducing pollutants that are present indoors assuming that those outside are in fact cleaner.