Well designed fresh air systems that are added to a building or existing systems that are improved to ensure they supply the correct volumes of fresh air have proven to increase employee alertness and satisfaction, resulting in increased performance levels and therefore profitability.

M&R Airflow Limited is accomplished at designing and installed fresh air Ventilation Systems for all types of building, by exploiting the latest technology advances we can provide energy efficient and passive fresh air Ventilation Systems that keep running costs to a minimum for the benefit of you our Customers.

Utilising our in-house resources a fresh air Ventilation System could be installed within your premises on a Fast Track basis, and integrated with the existing building structure and aesthetics.

Extract Systems

In buildings where comfort conditions are important or the building structure limits the flow of contaminated air from the building then in conjunction with the above Fresh Air Ventilation System an Extract Ventilation System can be installed within the building structure to remove contaminants such as odours, carbon dioxide and ozone (from Photocopiers) to ensure that the fresh air system is running at its maximum performance and that fresh air levels are maintained.
M&R Airflow Limited is accomplished at the design supply and installation of Extract Ventilation Systems for all types of building/application.

Heat Recovery Ventilation Systems

There are three main types of Heat Recovery Ventilation Systems these being:
Heat Recovery Cube (Plate Heat Exchanger)
Thermal Wheel (Rotary Heat Exchanger)
Run-around Coil Heat Exchanger.

Heat Recovery Cube (Plate Heat Exchanger)

Heat Recovery Cubes operate by exchanging heat from the extract air being removed from the building/room and passing it on to the fresh air entering the building/room; this is a very efficient system and provides substantial running cost savings.
The important advantages of this type heat exchanger are:
1) Exchange is carried out without mixing of the extract and supply air.
2) That the heat recovery cube has no moving parts or motors ensuring that all of the efficiency is retained.
3) There are no additional maintenance issues/costs.
4) The heat exchange also works in summer when the building is being cooled by an air conditioning system; the incoming fresh air is cooled prior to entering the building/room reducing the load on the air conditioning system.
5) Generally the efficiency of this type of this system is approximately 50-60% heat recovery but can be up to 75%.
This type of system is generally limited to installation within a combined fresh air/extract Air Handling Unit however it is possible to retro-fit within the supply and extract ductwork systems of an existing ventilation system.

Thermal Wheel (Rotary Heat Exchanger)

The Thermal Wheel operates in a very similar manner as the Heat Recovery Cube by exchanging heat from the extract air being removed from the building/room and passing it on to the fresh air entering the building/room; the important differences of this exchange of heat in comparison with the Heat Exchange Cube is that:
1) The Thermal Wheel takes up considerable less space than a Heat Recovery Cube.
2) There are additional maintenance issues/costs.
3) Additional running costs will be involved.
4) Generally the efficiency of this type of this system is approximately 50-60% heat recovery.
As with a Heat Recovery Cube this type of system is generally limited to installation within a combined fresh air/extract Air Handling Unit however it is possible to retro-fit within the supply and extract ductwork systems of an existing ventilation system.

Run-around Coil Heat Exchange

The Run-around Coil type Heat Exchanger operates in a slightly different manner than the Heat Recovery Cube or Thermal Wheel in that the system utilises a water/ethylene glycol mix flowing between two coils one mounted within the extract ductwork or extract fan unit and the other mounted within the fresh air duct or Air Handling Unit. The two coils are connected together by a pipework system that incorporates a pump; the system exchanges heat being removed from the
room/building via the extract air and passing it on to the fresh air entering the building/room through the water medium; the important differences of this exchange of heat in comparison with the Heat Exchange Cube or Thermal Wheel is that:
1) The Run-around Coil Heat Exchanger takes up considerable less space than a Heat Recovery Cube.
2) There are additional maintenance issues/costs.
3) There are additional running costs.
4) Generally the efficiency of this type of this system is approximately 30-40% heat recovery

M&R Airflow Limited is accomplished at the design supply and installation of Heat Recovery Ventilation Systems for all types of building/application please call us on 0845 302 8280 for more information or a free quotation.

Kitchen Ventilation Systems

Kitchens can be very demanding environments not only for employees but also for the Ventilation Systems, especially when cooking with oil is carried out such as when Frying Pans, Deep Fat Fryers, Char grilles and Woks are used. It is important that the whole system is designed around your requirements and the use to which the Kitchen is to be used.

Where the Kitchen is hardly used apart from make drinks or warming up food then a simple Ventilation System would be required to remove odours and steam.

Small industrial Kitchens where cooking is carried out on a daily basis would require a more complex Ventilation System with Extract Hoods for steam and oil based cooking which would include grease filters and interface with the gas supply (to isolate the gas on failure of the ventilation). The system would also provide for a fan motor which is out of the air stream and with sufficient access panel provision to ensure all parts of the system can be cleaned on a regular basis. The Extract Hood would include both fresh air provision and extract with washable grease filters.

Large industrial Kitchens where cooking is carried out on a daily basis would may require more complex Ventilation System with Extract Hoods for steam and oil based cooking which would include grease filters and interface with the gas supply (to isolate the gas on failure of the ventilation), Electrostatic smoke fume control, UV (Ultra Violet Light) germ and odour control, Carbon Filter odour control systems. The system would also provide for a fan motor which is out of the air stream and with sufficient access panel provision to ensure all parts of the system can be cleaned on a regular basis. The Extract Hood would include both fresh air provision and extract with washable grease filters.

We can supply and install all types of specialised filtration systems to suit your requirements to include:
Pre and post filters.
Electrostatic precipitations - which collects grease and smoke fumes complete with pre and post filters.
UV-C Odour Control - this being a system of ultra violet lights to eliminate cooking odours. Please be aware that UV-C cannot remove smoke and therefore where a lot of smoke is produced, i.e. char grille, an electrostatic precipitator should also be used).
Carbon filter - odour control.

Our design services would include meeting you the Client with your Architect (if required) to discuss your requirements, a site visit to the premises (if available), provide a proposed scheme drawing including full filtration odour control systems required, attend design meetings, liaise with Architect, Structural Engineers, Other Services, Developer, Environmental Health Officer etc. Provide a written quotation for the installation.

Our Designers are fully conversant and experienced in the design of Kitchen and Restaurant Ventilation Systems.

We are also involved with the leading Kitchen Extract Filtration/Odour Control Companies and can advise you on the system most suitable for your operation.

We can supply ductwork which is fire rated and that satisfies BS476 Part 24:1987 for up to 4 hours stability, 4 hours integrity and 1 hour’s insulation in case of fire and fully complies with HVCA Specification DW171.

M&R Airflow Limited is accomplished at designing, supplying and installing Kitchen Extract Ventilation Systems of all types which will comply with HVCA (Heating and Ventilation Contractors Association) recommended specification DW 171.

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Fume Extract

The installation, maintenance and correct operation of fume cupboard systems is critical to many types of business. At M&R Airflow Ltd we can provide the supply, install, maintain, inspection and management of all types of Fume Cupboard systems and ensure that all of your statutory responsibilities are managed correctly, as well as providing fully documented service and maintenance system.

Fume Cupboards

Fume Cupboards with high levels of operator protection and practical design that provide full compliance with the latest COSHH regulations can be supplied and installed by M&R Airflow Ltd. The cupboards will provide a safe working environment for staff and simple to operate with easy to use controls, the units are easy to maintain therefore keeping maintenance costs to a minimum. The units are fully self contained with no external ducting required, the activated carbon filtration system ensures that any hazardous fumes are fully adsorbed within the filters (HEPA filters to class H13 of BS EN 1822-1 remove all types of particulate).

Biological Safety Cabinets

We can supply Biological Safety Cabinets with advanced control systems that are both versatile and reliable. Available in Class I, Class II or Class III/I ensures that a range of solutions is available for the containment of pathogens from category 1-4.

Laminar Flow Areas

Modern production methods such as silicon chip manufacture often demand an environment cleanliness standard where the air flow pattern, the temperature and humidity is specifically controlled and monitored. At M&R Airflow Limited we can create these specialist areas to integrate fully with your production facility. We can provide full design and installation package to meet your individual needs and specification.

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Smoke Extract

Fire and Smoke Control Systems

A local authority Fire Officer will often specify fire or smoke control systems for buildings when a specific requirement is required. We can design, supply, install and commission both ventilation and air conditioning systems to incorporate local authority requirements for fire or smoke control or removal.

Air Curtains

Air curtains fulfil a specific task of either keeping out cold air from a heated environment (for example shop where the doors need to remain open to attract passing trade) or keeping out warm air from a cooled environment (for example a cold room where the door needs to be open for fork lift truck operation). Air curtains can be supplied in vertical or horizontal options, with a wide range that covers economical air curtains for small shop doorways to large industrial system for warehouses. Air curtains can be supplied in almost any colour or finish from standard white to polished stainless steel, from standard units to elegantly designed bespoke units which are individually crafted to meet the architectural designs/requirement of prestigious buildings and stores. Modern air curtains incorporating the latest in air curtain technology advances, deliver optimum performance and efficient operation all day every day. These technological advances include the use of heat pump inverter technology where CO2 emissions and running costs can be reduced by 67% where the installation cost can be repaid in two and half years and where an open door policy becomes more energy efficient and environmentally friendly.

M&R Airflow Limited will guide you through the entire process of selecting the correct Air Curtain for your unique requirements, from initial concepts, specification, installation, commissioning, training and handover all developed around your budget.

Odour Control

The control of odour can be important issue when associated with production processes such as an industrial process or cooking. M&R Airflow Limited can offer systems where odour can be readily controlled, either with the use of conventional filtration (pre filters and bag filters) or through the use of carbon filtration, Hepa filters, commercial air washing or biologically active vegetable material. A well designed fresh air and extract system, coupled with odour control can have beneficial effect on personnel performance, the environment and neighbour relations.

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Natural Ventilation

Air conditioning and mechanical ventilation have been for decades the standard method of environmental control in many building types especially offices. Global warming, pollution and dwindling energy supplies have led to a new environmental approach in building design. Innovative technologies along with bioclimatic principles and traditional design strategies are often combined to create new and potentially successful design solutions. Natural ventilation is the process of supplying and removing air through a building by natural means. There are two types of natural ventilation available in buildings these being wind driven ventilation and stack ventilation. The pressures generated by buoyancy also known as 'the stack effect', are quite low (typical values: 0.3 Pa to 3 Pa) while wind pressures are usually far greater (~1 Pa to 35 Pa). The majority of buildings employing natural ventilation rely primarily on wind driven ventilation, but stack ventilation has several benefits. The most efficient design for a natural ventilation building should implement both types of ventilation.

The Stack effect system is induced by temperature, when a temperature differential exists between two adjoining volumes of air the warmer air will have lower density be therefore be more buoyant and will rise above the cold air creating an upward air stream.

In order for a building to be ventilated adequately via stack effect the inside and outside temperatures must be different so that warmer indoor air rises and escapes the building at higher apertures, while colder, denser air from the exterior enters the building through lower level openings. Stack effect increases with greater temperature difference and increased height between the higher and lower apertures. The neutral plane in a building occurs at the location between the high and low openings at which the internal pressure will be the same as the external pressure (in the absence of wind). Above the neutral plane, the air pressure will be positive and air will rise. Below the neutral plane the air pressure will be negative and external air will be drawn into the space.

• The advantages of stack effect ventilation:
  The system does not rely on wind; ventilation will take place on still, hot summer days.
  The effect is a naturally occurring force hot air rises, no fans are required.
  Relatively stable air flow (compared to wind).
  Greater control in choosing areas of air intake (compared to wind).
  Environmentally friendly and sustainable method of ventilating buildings.
• Disadvantages/limitations of stack driven ventilation:
  Lower magnitude compared to wind ventilation.
  The system relies on temperature differences (inside/outside).
  Design restrictions such as height or location of apertures.
  The quality of air it introduces in buildings may be polluted for example due to proximity to an urban or industrial area.

Natural ventilation in buildings relies mostly on wind pressure differences but stack effect can augment this type of ventilation and partly restore air flow rates during hot, still days. Stack ventilation can be implemented in ways that air inflow in the building does not rely solely on wind direction. In this respect it may provide improved air quality in some types of polluted environments such as cities. Wind can augment the stack effect but also reduce its effect depending on its speed, direction and the design of air inlets and outlets. Therefore prevailing winds must be taken into account when designing for stack effect ventilation.

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Solar Chimney (Thermal Chimney)

The thermal chimney is a way of improving the natural ventilation of buildings by using convection of air heated by passive solar energy. A simple description of a thermal chimney is that of a vertical shaft utilizing solar energy to enhance the natural stack ventilation through a building. The thermal chimney has been in use for centuries, particularly in the Middle East, as well as by the Romans.

The solar chimney is a concept currently being explored by scientists as well as designers, mostly through research and experimentation for use in future building design.

A thermal chimney can serve many purposes. Direct solar gain warms air inside the chimney causing it to rise out the top and drawing air in from the bottom. This drawing of air can be used to ventilate a home or office, to draw air through a geothermal heat exchange, or to ventilate only a specific area.

Natural ventilation can be created by providing vents in the upper level of a building to allow warm air to rise by convection and escape to the outside. At the same time cooler air can be drawn in through vents at the lower level. Trees may be planted on that side of the building to provide shade for cooler outside air.

This natural ventilation process can be augmented by a solar chimney. The chimney has to be higher than the roof level, and has to be constructed on the wall facing the direction of the sun. Absorption of heat from the sun can be increased by using a glazed surface on the side facing the sun. Heat absorbing material can be used on the opposing side. The size of the heat-absorbing surface is more important than the size of the chimney. A large surface area allows for more effective heat exchange with the air necessary for heating by solar radiation. Heating of the air within the chimney will enhance convection, and hence airflow through the chimney. Openings of the vents in the chimney should face away from the direction of the prevailing wind.

To further maximize the cooling effect, the incoming air may be led through underground ducts before it is allowed to enter the building. The solar chimney can be improved by integrating it with a Trombe wall. The added advantage of this design is that the system may be reversed during the cold season, providing solar heating instead.

A variation of the solar chimney concept is the solar attic. In a hot sunny climate the attic space is often blazingly hot in the summer. In a conventional building this presents a problem as it leads to the need for increased air conditioning. By integrating the attic space with a solar chimney, the hot air in the attic can be put to work. It can help the convection in the chimney, improving ventilation.

The use of a solar chimney may benefit natural ventilation and passive cooling strategies of buildings thus help reduce energy use, CO2 emissions and pollution in general. Potential benefits regarding natural ventilation and use of solar chimneys are:

Improved ventilation rates on still, hot days
Reduced reliance on wind and wind driven ventilation
Improved control of air flow though a building
Greater choice of air intake (i.e. leeward side of building)
Improved air quality and reduced noise levels in urban areas
Increased night time ventilation rates
Allow ventilation of narrow, small spaces with minimal exposure to external elements

Potential benefits regarding passive cooling may include:
Improved passive cooling during warm season (mostly on still, hot days)
Improved night cooling rates
Enhanced performance of thermal mass (cooling, cool storage)
Improved thermal comfort (improved air flow control, reduced draughts)

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Windcatcher

A windcatcher is a traditional Persian architectural device used for many centuries to create natural ventilation in buildings. It is not known who first invented the windcatcher, but it still can be seen in many countries today. Windcatchers come in various designs, such as the uni-directional, bi-directional, and multi-directional.

The windcatcher functions on several principles:
First, a windcatcher is capped and has several directional ports at the top (Traditionally four). By closing all but the one facing away from the incoming wind, air is drawn upwards using the Coanda effect, similar to how opening the one facing the wind would push air down the shaft. This generates significant cooling ventilation within the structure below, but is not enough to bring the temperature below ambient alone - it would simply draw hot air in through any cracks or windows in the structure below.

Therefore, the key to generating frigid temperatures seems to be that there are very few cracks at the base of the thick structure below, but there is a significant air gap above the qanat. A qanat has quite a lot of water inside, because there are frequent well-like reservoirs along its path. Completely shaded from the sun, a qanat also aggregates the cold, sinking air of the night, which is then trapped within, unable to rise up to the less dense surface air. A windcatcher, however, can create a pressure gradient which sucks at least a small amount of air upwards through a house. This cool, dry night air, being pulled over a long passage of water, evaporates some of it and is cooled down further.

Finally, in a windless environment or waterless house, a windcatcher functions as a stack effect aggregator of hot air. It creates a pressure gradient which allows less dense hot air to travel upwards and escape out the top. This is also compounded significantly by the day-night cycle mentioned above, trapping cool air below. The temperature in such an environment can't drop below the nightly low temperature. These last two functions have gained some ground in Western architecture, and there are several commercial products using the name windcatcher.

When coupled with thick adobe that exhibits high heat transmission resistance qualities, the windcatcher is able to chill lower level spaces in mosques and houses in the middle of the day to frigid temperatures.
So effective has been the windcatcher in Persian architecture that it has been routinely used as a refrigerating device for ages. Many traditional water reservoirs are built with windcatchers that are capable of storing water at near freezing temperatures for months in summer. High humidity environments destroy the evaporative cooling effect enjoyed in the dry conditions seen on the Iranian plateau; hence the ubiquitous use of these devices in drier areas such as Yazd, Kashan, Nain, and Bam. This is especially visible in ab anbars that use windcatchers.

A small windcatcher (badgir) is called a "shish-khan" in traditional Persian architecture. Shish-khans can still be seen on top of ab anbars in Qazvin, and other northern cities in Iran. These seem to be more designed as a pure ventilating device, as opposed to temperature regulators, as their larger cousins in the central deserts of Iran are.

Natural Ventilation

The natural ventilation works on aerodynamic principles, these include cross ventilation, rising warm air and suction created by wind passing over a high level opening. The ductwork for the units themselves can pass through any floor level to take warm air from within the building. Natural ventilation units are usually controlled via a control panel link to room mounted temperature and Co2 sensors. They can also be supplied in a manually operated system where the dampers can be opened and closed by use of a rotating lever operated by the room occupants when required.

The natural ventilation system can be installed on flat or pitched roofs and also on the roof apex where appropriate and consists of a chimney with dampers and transfer grilles. Manufactured to suit most architectural design requirements the units are fully welded and constructed using corrosion resistant aluminium and fitted with internal acoustic material. Adjustable dampers and transfer grilles are manufactured from anodised aluminium or perforated stainless steel panels. The units may also be powder coated to your specifications in any RAL colour of your choice.

Ventilation Maintenance

The proactive maintenance of ventilation systems is essential, regular proactive maintenance ensures the equipment runs at maximum efficiency; highlights possible failures before they occur, thus allowing repairs to be programmed at times when the equipment would not be running. In the case of the Kitchen Extract systems and fume extract it is a legal requirement that the systems are inspected, tested and maintained to an established programme. In many cases, the supply and extract fans are rarely maintained and are found to need complete replacement when they fail. Regular routine servicing will prevent this and M&R Airflow Limited can provide a planned maintenance service to ensure that these valuable assets continue to perform as originally designed and meet or exceed their predicted life expectancy.

For more assistance call us now on 0845 302 8280 for your Free No Obligation Consultation, Site Survey and Written Quotation.