AHUs. Direct, Zone-Specific, Demand Controlled Ventilation AWARDS VENTILATION PRODUCT. For consistently good indoor air quality WINNER 2012

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1 Direct, Zone-Specific, Demand Controlled Ventilation BMS DATA LO GG ER For consistently good indoor air quality AHUs AWARDS VENTILATION PRODUCT WINNER 2012 Scan to visit website Rev: /2012

2 BMS DATA LO GG ER AHUs Enhancing ventilation since 1991 Traditional centrally ducted ventilation systems have their pros and cons... but just imagine if you could enhance the pros while minimising - or even eliminating - the cons. Furthermore, can you imagine ventilation systems in airtight, highly insulated buildings that enhance the activity and comfort of the occupants and are an integral part of the building s energy management systems? This was the vision of Henrik Staehr and Kim Jensen in 1991, when they established AirMaster, Denmark. And yes, they succeeded! Today, AirMaster offers an extensive range of direct ventilation solutions as a low energy, responsive, demand controlled alternative to central ductwork systems. Henrik Staehr and Kim Jensen Effective ventilation where it s needed, when it s needed. AirMaster headquarters in Aars, Jutland, Denmark

3 Central Ducted Systems The design of centrally ducted ventilation systems in buildings requires extensive ductwork systems. In operation, centralized air handling units require considerable fan power to keep all building air in circulation. AirMaster Direct Concept With AirMaster, direct ventilation units are installed only in those rooms where fresh air is required. Ductwork connections for each unit are limited to just two penetrations through an external wall, enabling significant savings in fan power. Building with traditional ducted ventilation Building with AirMaster demand controlled AHUs AirMaster ventilation pathways

4 BMS DATA LO GG ER AHUs Demand Controlled Ventilation (DCV) What is DCV? Demand controlled ventilation is a cost effective method of maximizing indoor air quality. Local sensors are used to monitor ambient conditions in ventilated spaces and provide real-time feedback to the zone controller. The controller responds either by regulating ventilator fan speed or by adjusting the position of ductwork dampers. The result is that ventilation provision is kept in step with the specific needs of the building occupants. All AirMaster fans are driven by electric motors using electronic commutation (EC), which enables accurate modulation to the required speed. This enables better control than that offered by motor speed adjustment only through discrete settings. Why use DCV? To ensure good indoor air quality Substantial carbon saving potential - only used as required Low payback period compared to central systems Why is Indoor Air Quality (IAQ) important? Where ventilation in a room is inadequate, heat and carbon dioxide (from occupants and computer equipment) can build up to uncomfortable levels. A high carbon dioxide level makes a room feel stuffy. Without correction of this, occupants can be expected to suffer drowsiness and impaired concentration. On the other hand, effective ventilation produces good IAQ with the benefits to occupants of alertness, improved concentration and an overall feeling of wellbeing. SBEM and DCV Consultation notes (issued in 2012) concerning Building Regulations suggest that in future versions of SBEM, the notional building will be assumed to incorporate demand controlled ventilation. Hence, any new building designed without DCV can be expected to score poorly when compared to the notional building. AirMaster AM 100 AHU

5 Counterflow Heat Recovery AirMaster systems include counterflow heat exchangers to ensure the efficient recovery of heat from extracted air. By virtue of AirMaster s direct approach, each heat exchanger is contained within the associated room envelope, which means that ductwork requirements are minimal. Heat loss through such ducts is negligible, which cannot be said of long ductwork systems as used in centralized systems. AirMaster heat exchangers conform to EN308 and have a heat recovery efficiency of at least 84% (dry bulb). Typical heat recovery efficiencies: Variable Speed Fan Power EC Motors AirMaster AHUs are based on advanced fan technology, ensuring low energy consumption and long service life. Electronic commutation of fan drive motors enables linear modulating control. Specific Fan Power (SFP) is between w / l / sec for the AirMaster AM range. Calculation of SFP takes account of both fans, electronic control and the damper actuators. Counterflow plate heat exchanger 80% < η t Rotary heat exchanger 70% < η t < 80% Parallel Plate heat exchanger 55% < η t < 70% Heat Pipe and others 45% < η t < 55% Integrated fan & EC motor assembly EXHAUST INTAKE Carbon saving calculator ED OT IF F2 FI PI PU ET MD HE BP * RT FL EF EXTRACTION FT CT CH * + IT Schematic of typical AirMaster unit INLET Name of component F1 Inlet fan F2 E xhaust fan IF Fresh air filter EF E xhaust air filter MD Main damper (motorised) ED E xhaust damper (overpressure) BP Bypass damper (optional) BP HE CT FT RT/FL OT ET Bypass damper (optional) Countercurrent heat exchanger Condensate tray Float Extract temperature sensor/flow sensor Outdoor temperature sensor Exhaust temperature sensor ET PI/PU CH IT Exhaust temperature sensor Connection for pressure gauge for airflow-meas - urement, inlet/extraction Comfort heating surface (optional) Inlet temperature sensor

6 BMS DATA LO GG ER AHUs EN F5 Filters as Standard / F7 Optional Indoor air quality AirMaster AHU units are provided with filters in both the fresh air intake and exhaust pathways. The filters conform to the requirements of EN 13779, (European Norm which includes guidance on filter selection - ventilation equipment installed in non-residential buildings). F5 Class filters are included as standard, with F7 offered as an alternative where external environments are expected to have a high burden of contaminants. Ensuring continued energy saving Class F5 filters are sturdy, long-lasting and effective. This means not only that indoor air quality is optimized, but also that heat exchanger surfaces are kept clean. This promotes and maintains a high level of heat exchange efficiency. If filters of lower standard (eg Class G) were used instead, the heat exchanger could be expected to show signs of deposits in just a few months. This would have adverse effects on thermal efficiency and specific fan power.

7 Noise Emissions - The Unbelievable Truth Acoustics AirMaster has one of the lowest noise profile within the industry. Each unit is rated at no more than 35 db(a) at 1m. For areas involving high sensitivity to noise (e.g. schools for children with special educational needs), AirMaster units can be set to run at 80% capacity, reducing noise further to 30 db(a) at 1m. AM 800 AHU installed in a classroom AM 500 AHU Sound Pressure Level, 1m Noise Measurement - Keeping it Simple Because each AM unit is self-contained, sound pressure levels can be measured with accuracy providing reliable predictive noise level values. There is no risk of noise ingress, as can happen with ductwork systems that pass through plant areas or other occupied spaces. 35dB(A) at 1m is the sort of noise level you d expect in a library Floor Standing AM 900 AHU

8 BMS DATA LO GG ER AHUs Scandinavian Design One of our main aims when designing AirMaster s air management units was to achieve a discreet unit which would aesthetically blend into a room. A recognisable characteristic of the AirMaster AHU is its cubic design and the way it is horizontally segmented. By breaking the unit up into segments, each unit appears much lighter and more streamlined, making it less dominant in a room. Along with this, the ventilation grilles are designed to harmoniously fall in line with the rest of the unit and the room. This discreet and distinct design enables the AirMaster AHU to become more of an integrated architectural element. AirMaster s light and clean-cut lines are in keeping with traditional Scandinavian design, as practiced daily at Design-People. Klaus Schroeder MA, Industrial Designer, Partner & CEO Design People AirMaster AHUs Key benefits Provide good indoor air quality Efficient heat recovery = a true low carbon solution Excellent specific fan power means that running costs are low Easy to install additional capacity with changes to building usage. The quickest route to a fresh indoor environment Through-the-wall or through-the-roof installation Unobtrusive mounting against wall or ceiling No extensive ductwork required, therefore: No suspended ceilings required System can be expanded one room at a time A B

9 Choosing the right unit The size, location and purpose of each room must all be considered when providing good ventilation. AirMaster units up to AM 800 can be mounted against the ceiling, or partly recessed into the ceiling void. WALL EXHAUST OPTION Fresh air intake and exhaust ducts are run sideways through the wall on which the unit is mounted. The openings in the outside wall are finished off with louvered gratings (as for photo B). Possible interaction from space heating and air-conditioning systems must also be anticipated, and SAV are well placed to advise on this. ROOF EXHAUST OPTION As for the wall exhaust, mounting is also on the wall but with the fresh air and exhaust penetrations run upwards through the roof (ref photo B). External finishing is by roof caps and flashings. Ceiling unit without recess as seen in photo B (opposite page) Options for mounting In all cases, AirMaster units move supply air along the ceiling, exploiting the so-called Coanda effect. This occurs when air hugs the ceiling as when passing over a reverse aerofoil, so that when it eventually falls into the room, it does so at some distance from the AHU. USING CEILING VOID RECESS To reduce visual impact, either 1/3 or 2/3 of unit depth can be concealed within the ceiling void space (ref photo A). External facing panels need only be provided for the visible portion. Recessing can be used with duct connections either through the wall or roof, with unit mounting either on the wall or ceiling. Bottom panel access for easy maintenence Partly recessed ceiling unit as seen in photo A (opposite page)

10 BMS DATA LO GG ER AHUs Floor Standing Models Floor mounted AirMaster AHUs can be positioned so as to circulate air from one side, or both sides. How do they work? SAV s AirMaster direct, low noise air handling units (AHUs) provide energy efficient, zone-specific ventilation with heat recovery. Demand control gives rapid response to local indoor air quality (IAQ) requirements. Corner positioning (plan) Mid-wall positioning (plan) AirMaster units can be installed in different ways to suit a range of spaces, ensuring optimum circulation of air and providing an environment which is fresh, comfortable and productive. Corner and mid-wall positioning (elevations) Each of these positions gives a distinctive air circulation pattern, as shown in the diagrams above. Colour options Lacquered medium density fibreboard (MDF) surface panels can be supplied in any of the 8 colours shown below, as standard. Floor standing AirMaster AHUs installed in a day care centre Where a different RAL colour is chosen, arrangements can be made to provide this at a modest additional charge. FLOOR MOUNTED MODEL is free standing and can be positioned along the room periphery, or as a means of partitioning a room. The floor standing range by AirMaster includes the AM 900 & AM 1200 AHU.

11 Technical Data Summary AM Maximum capacity at 35 db(a) m3/h Maximum capacity at 30 db(a) m3/h Throw (max.) m Weight (ventilation units without options) kg Colour, panels RAL 9010 (white) Dimensions (L x D) mm 1170 x x x x x x 496 Dimension (H) mm Min. room height for horizontal intake/exhaust mm Min. room height for vertical intake/exhaust mm Electrical connection Ph & V 1~230 1~230 1~230 1~230 1~230 1~230 / 3~230 Frequency Hz Power consumption (max.) W Operating current A Power factor Leakage current (max.) ma CC Cooling unit Cooling capacity W Power consumption W Operating current A Leakage current (max.) ma Weight kg Electrical heating surface Electrical heating surface (comfort heating) W Operating current A Water heating surface Capacity at flow/return temperature of 70/40 C W Capacity at flow/return temperature of 65/35 C W Standard or Optional Control Features Inbuilt data logger CO 2 sensor wall-mounted / Integrated PIR motion sensor Humidity sensor / Condensate pump Thermostat BMS

12 BMS DATA LO GG ER AHUs Controls Data logging for unit performance monitoring AirMaster units come with integral data logging and display. Data storage enables performance analysis and diagnostics of any shortfalls, helping to keep operations and air quality optimised. Basic features and controls AirMaster s ventilation system can be optimised for local operating conditions using the features below: Manual start and stop via the control panel Automatic operation using programmed weekly schedule Background ventilation as constant basic ventilation with reduced minimum airflow Free night cooling Start and stop using external switches such as thermostat and hygrostat Start and stop using motion (PIR) sensor CO 2 sensor either to start and stop the unit or control the airflow Automatic operation using a BMS system Automatic bypass control

13 Wall mounted CO 2 sensor Integrated CO 2 sensor Start / stop and control by CO 2 sensor AirMaster units can be controlled to start / stop and automatically adjust the air flow using signals from a CO 2 sensor. This function is particularly suited to schools, academies and universities. Humidity Sensor PIR/Motion sensor Start / stop control by humidity sensor Ventilation can be arranged so as to monitor and control relative humidity (RH). AirMaster hydrostats have a humidity measuring element of stabilised synthetic gauze. They can be used with either minimum or maximum settings and can operate within a range of 25-95% RH. Hydrostats are suited to systems designed for a constant base level of ventilation, with the dehumidify signal used to take the unit to full power. Start / stop control by motion sensor (PIR) The ventilation system can be set to start / stop using a signal from the Permanent Infra Red (PIR) sensor. When this signal ceases, the ventilation unit does not stop immediately. Rather, it continues in operation for a further pre-set period of say, 30 minutes, to maintain steady conditions in the event of an occupant s return.

14 BMS DATA LO GG ER AHUs Automatic Bypass Control for Free Cooling of Supply Air Should room temperature increase beyond the desired setting, an automatic bypass damper diverts a portion of incoming fresh supply air around the counterflow heat exchanger. This bypass air remains at external conditions and helps to bring down the temperature of the re-combined flow of supply air, thus reducing room temperature. During periods of hot weather, night time operation by AirMaster units takes advantage of the thermal mass of the associated building. The temperature of supply air during night hours can be expected to fall, and movement of this air into a room would effectively cool down the room surface areas. As temperature increases again the following day, supply air would be cooled as it passed over the same surface areas. Night cooling is at the cheapest electricity tariff, helping to reduce the cost of daytime operation by supplementary coolers. Where external temperatures of over 30 0 C at 40% RH can be expected, AirMaster offer dedicated cooling units. These are designed to reduce supply air temperature by up to 15 0 C. Cooling units are dimensionally compatible with all horizontally mounted AM models and can be readily integrated with the associated control panels. Supplementary Heating To avoid any feeling of draught on cold days, heating can be provided to the supply air pathway, just before entering the room. Heating can be by finned water tube or electric element. Automatic Condensate Control Aluminium Heat Exchangers AirMaster counterflow heat exchangers are made of pressed aluminium elements. They have a thermal efficiency of 84% (dry bulb) and 91% (80% indoor RH). The natural conductivity of aluminium enables internal air pathways to be kept wide. The heat exchanger elements have Counterflow Heat Exchanger a free space of 3.4mm between plates and individual passageway areas of 60mm 2. This means that the specific circumference (= ratio of circumference / area) is kept below 1.0, reducing the risk of condensate blockage thereby ensuring consistently good indoor air quality. Condensate Removal With heat recovery of up to 91.0%, exhaust air is cooled significantly and this can lead to the formation of condensate. This is led to a collection tray. Normally, this condensate evaporates into the exhaust air. However, if conditions prevent this happening and the quantity of condensate increases, this would be detected by a float sensor. The resultant signal would then reduce the flow of fresh air and increase exhaust flow. In this way, the condensate is encouraged to evaporate, leading to the condensate sensor being deactivated. Where a high level of humidity is anticipated, either a manual condensate drain or condensate pump can be provided.

15 BMS System The AirMaster BMS (Master/Slave) Network can control up to 16 AHUs from a single control panel. AirMaster supports various types of BMS system: KNX N BACnet TM / IP BACnet TM MS / TP LON MODBUS RTU RS485 The figure shows a Master/Slave System with a central control panel and two sensors (e.g. PIR and CO 2 ) in each room Working together, AirMaster and BMS can: Display and log all information (sensors and equipment status) for operation, performance monitoring and carbon reduction assessment Enable remote adjustment of set points Activate night cooling Process alarm signals e.g. filter change notification Provide information from CO 2, PIR or humidity sensors Enable remote diagnostics of equipment performance

16 External Views of AirMaster AHUs We hope you have found the contents to be of interest. For further information, or to request an AirMaster product brochure, please call us on: or us at For further information on any aspect of direct, zone-specific, demand controlled ventilation, please contact: SAV Systems, Scandia House, Boundary Road, Woking, Surrey GU21 5BX Tel: +44 (0) Web: