Proper ventilation is essential to maintaining good air quality in any environment. There’s no excuse for poor air circulation, especially since, when integrated with the heating system, ventilation is free, as Dave Garvey of Nordair Niche explains.
I
n commercial buildings, good ventilation will keep bad odours, irritating pollutants and potentially harmful gases like carbon monoxide at bay. Plus, it prevents the formation of mould and/or mildew, which is vital for employee health and building hygiene – especially important when in a kitchen or food processing environment. When production processes get under
way, air quality can quickly deteriorate. Raised levels of indoor air pollution may reduce productivity, as well as having negative effects on the comfort of the building’s occupants. Certain industries are prone to airborne particles that can make life very unpleasant. Automotive manufacturing processes, for example, produce oil haze that hangs in the air. In other industries, chemical processes may generate foul vapours.
The use of chemicals or other hazardous substances at work can put people’s health at risk. Diseases including asthma, dermatitis or cancer can result from poor ventilation. The COSHH (Control of Substances Hazardous to Health) regulations require employers to control substances that can harm workers' health. As a minimum, ‘a good standard of general ventilation and good working practice’ is required. For very hazardous substances, extract ventilation is often required, but a good level of ventilation that will maintain air quality can be achieved easily and cheaply
– and without the need for additional equipment – through the heating system. Combined heating and ventilation solutions have been on the market for many years. The technology has been developed to the point that they now offer optimum energy efficiency while improving air quality. These systems rely on a degree of fresh air intake to operate. Nordair Niche direct and indirect gas-fired units, for example, provide both fresh and warm air in the building. Direct fired units work on a patented air recirculation system which supplies the amount of fresh air required to meet the changing requirements of the building, while maintaining a constant supply of fresh air into the burner. When fresh air is required, ventilation is quickly achieved as the dampers automatically adjust to provide the required amount of tempered outside air. The effect is almost instant as the fresh air is distributed evenly around the building. Since fresh air is delivered faster than it can escape by natural ventilation, these units slightly pressurise the air inside a building. Pressurisation causes the air to distribute evenly throughout, eliminating temperature stratification or ‘cold spots’ and ensuring every part of the building is usable at all times. Once optimum conditions have been reached, the system modulates the fresh air input and utilises up to 80% recirculated air for maximum economy. When temperatures within the building
Nordair Niche were able to develop a bespoke heating, ventilation and cooling system solution for McDonald’s Restaurants Ltd that reduced running costs, was transferable across sites and improved customer
experiences with a reliable, consistent and comfortable temperature inside all restaurants.
change, a combined heating and ventilation system can respond very quickly, soon returning the interior to comfort conditions. Heat recovery is fast becoming the norm for such ventilation systems, reducing both running costs and harmful CO2 emissions into the atmosphere.
This method of heating and ventilating premises does not require ductwork and is ideal for buildings requiring summer ventilation and regular air changes to maintain good air quality.
Combining the heating and ventilation functions gives optimum control and avoids the problem of co-ordinating and balancing separate heating and ventilation units. The combined system also has significant benefits on the operation of the heating, since the system utilises a large air volume/low discharge temperature principle.
A modulating burner and damper system, controlled electronically, ensures full co- ordination of the heating and ventilation functions. Between 20% and 100% fresh air may be utilised together with up to 80% re- circulated air. The 80/20 operation ensures excellent performance and low emissions. Working together with Mitsubishi Electric, Nordair Niche were able to develop a bespoke heating, ventilation and cooling system solution for McDonald’s Restaurants Ltd that reduced running costs, was transferable across sites and improved customer experiences with a reliable,
consistent and comfortable temperature inside all restaurants.
McDonald’s Restaurants Ltd were looking to create a comfortable environment for customers through a more energy efficient heating, ventilation and cooling system. The new Air Handling Unit from Nordair Niche is used for cooling, heating and ventilation and resulted in McDonalds Restaurants Ltd cutting their running costs by over £4500 for each site, whilst reducing their carbon emissions significantly. The fast food giant also saw a massive 35% reduction in energy consumption across 250 UK restaurants following the installation of the Air Handling Unit developed by manufacturers Nordair Niche and Mitsubishi Electric. Dave Holden Project Manager for McDonalds said: “It is commercially critical for us to operate effectively all year round. Our customers expect McDonald’s to have a comfortable internal temperature and the ability to offer that, reliably and consistently, is part of our relationship with customers. “When we started looking at replacing our air conditioning equipment we quickly realised we needed a bespoke system. We were coming at this with very specific requirements and off-the-shelf systems didn’t satisfy the need.”
The innovative solution combined Nordair Niche’s IDF Air Handling Units with Mitsubishi Electric’s Air Source Heat Pumps which were controlled by a Trend building Energy Management System to achieve maximum operating efficiency. Following an initial trial in two restaurants, the results were impressive and saw an annual saving of £4,515 per year and on average 20 tonnes less CO2 emitted. The solution was designed to accommodate a variety of standard sized Air Handling Units previously installed so that the replacement solution could be rolled out across all 1200 restaurants.
Intelligent combined heating and ventilation units are also an ideal cost effective and fuel-efficient solution for a variety of industrial applications, warehouse and logistics, bars and restaurants.
www.nordairniche.co.uk
Thermal destratification – not just an after thought Thermal destratification is simple, effective and highly energy efficient.
Simon Garratt, Marketing Manager for Reznor of Nortek Global HVAC explains why.
hermal stratification is a natural process that causes warm air to rise to the ceiling or roof space of a building and displaces cooler air pushing it downwards to the occupied space. Every building will experience a degree of thermal stratification and in high buildings such as factories, warehouses and sports halls, this can result in high temperature gradients and increased energy usage.
T
In the majority of working environments employees need to be kept warm up to 2m from ground level so any energy used to heat air above this point is wasteful. Temperature differences between the working area and the roof of the building can be up to as much as 5 degrees which is a significant amount of wasted energy.
Destratification fans are the ideal solution, working with a warm air heating system to move warm air from the height of the building back down to the working environment at ground level. It is estimated by the Carbon Trust, that these fans can reduce energy consumption by an estimated 20%.
Maximisor destratification fans reverse the natural convection process re- circulating warm air back to working level providing a permanent reduction in roof space temperature and temperature distribution.
Benefits
An efficiently designed destratification system ensures the effective distribution of heat throughout a building’s space, so that
stratification is minimalised to provide a nominal temperature difference between the working area and the roof space. This then ensures the reduction of the temperature in the roof area and rate of heat loss through the roof giving a
substantial reduction. Destratification
fans are able to reduce a building’s running costs as they improve the distribution of warm air making it possible to maintain the required temperature in the working area with fewer warm air heaters. In buildings such as warehouses, the destratification fans will also re-circulate heat generated
by machinery ensuring less energy is consumed by the heating system. This also helps to prevent hot and cold spots in the working area and provides a more comfortable working environment for employees. In the summer, the fans can be used to provide cool draughts of air. Destratification
fans provide the ideal, cost
effective, energy efficient solution; make sure they’re not an after thought to your HVAC system.
ww.reznor.co.uk AUGUST 2015 BUILDING SERVICES & ENVIRONMENTAL ENGINEER 23
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40