Frequently Asked Questions
1. General Questions
2. School Questions
3. Recommended Reading
General Questions
What does HVAC stand for?
HVAC stands for Heating, Ventilation & Air Conditioning
How does a heat exchanger work?
Please see The Technology and Heat Exchangers (Concept)
What product is best for me?
See Selection Software for customised selections.
Why is fresh air so important in buildings?
Buildings require a constant supply of fresh air to maintain a healthy indoor environment. Allergens, mould and other bacteria can build up in enclosed spaces - so higher levels of fresh air are always required.
Conventional air conditioners require plenty of energy to provide cooling or heating. Air Change instead utilises the core heat exchange technology to minimise the energy output needed to condition outdoor air. This allows for greater outdoor air levels to supply higher indoor air quality, with a significantly reduced energy consumption penalty.
Are energy efficient HVAC systems still as powerful as conventional air conditioners?
Yes. Air Change units are just as powerful as other conventional air conditioners, but offer greater energy efficiency. The core heat recovery technology reduces the amount of energy used to heat or cool supply air without affecting its performance.
Does Air Change do both sensible and latent cooling?
Yes. The Air Change enthalpy exchanger does both sensible and latent cooling. If you only require sensible cooling, you can select the sensible heat exchanger. Each Air Change unit can be customised to specifically suit your needs.
Does Air Change serve domestic or commercial markets?
Air Change has products to suit both the domestic and commercial markets. Please see our Product Page for more information, or our Selection Software for help in choosing the correct product.
Air Change is a manufacturer of HVAC products. If you have a reliable installation firm that you have used before, you can get them to call Air Change to supply any technical information they may require.
Does Air Change make air conditioners as well as ventilation equipment?
Yes. Air Change’s Energy Recovery Ventilators (ERVs) operate with an existing high wall split, in ceiling or under ceiling air conditioners. In Ceiling ERVs are suitable for individual rooms such as small offices and classrooms. Your local Installation Contractor will know which brand has a good service history in your region. Get them to contact Air Change for more information.
For larger installations such as school halls, auditoriums, gymnasiums, laboratories, offices and indoor swimming pools, Air Change has a complete range of packaged units. These offer ventilation and air conditioning in one convenient unit. We also make Air Handling Units used in conjunction with chillers or chilled beams for multi-storey applications. Larger projects require a Consulting Engineer or Design & Construction firm to submit the air conditioning specifications to Air Change.
How do I choose an air conditioning installation firm?
Air Change can help provide contacts from a firm close to you. It is important to remember your installation needs to be executed by a licensed air conditioning company that is able to provide proper heat load estimation for the space. This will ensure you are paying for the right amount of air conditioning required.
Where do I purchase Air Change equipment?
The installing contractor will purchase Air Change products for your specific needs. For a complete list of contractors in your region, please contact your local State office.
Why should I choose Air Change products?
Air Change offers the most comprehensive heat recovery HVAC product range. Air Change is Australian owned and operated. It began as a family business and is now a publicly traded company, which is indicative of its growth. Air Change products are internationally patented and are designed and manufactured in Australia.
Where have Air Change products been installed? What types?
Air Change units have been installed widely across Australia. International installations are within New Zealand, Asia, The Middle East and Antarctica.
Please see our Projects page for more information.
What is the Section J of the Building Code of Australia?
Section J of the Building Code of Australia attempts to reduce energy consumption. Its aim is to "reduce greenhouse gas emissions by efficiently using energy" (http://www.energyefficiency.com.au/page115366.cfm).
Air Change complies with this objective, as our units are designed to reduce the energy load a conventional air conditioning system requires. This, in turn, reduces the total amount of energy that an air conditioner will use, thereby saving time, money and the environment.
School Questions
How much fresh air does a classroom require and why?
Studies by International Health in Education researchers have indicated that 10 litres per second per person (L/s/p) should be a minimum fresh air supply for classrooms. This ensures odour-free, oxygen-enriched (CO2 reduced) air for optimum learning and attentiveness. More fresh air in conditioned spaces leads to a more alert learning environment, less drowsiness and improved learning outcomes.
How does improved Indoor Air Quality (IAQ) influence asthma, colds and flu?
Improved ventilation and air quality reduces a range of respiratory illnesses, including common colds and influenza.
A recent review by Carnegie Mellon of five separate studies evaluating the impact of improved indoor air quality on asthma found an average reduction of 38.5% in asthma in building with improved air quality. An additional review by Carnegie Mellon found an average reduction of 51% of cold and flu cases in buildings with improved air quality.
Reference – Carnegie Mellon Uni Center for Building Performance 2005, http://www.arc.cmu.edu/cbpd/index.html
What is the best equipment for school classrooms?
For school classrooms, we recommend Air Change Energy Recovery Ventilators. Air Change does not make split units, so for this purpose we recommend a reliable high wall split in-ceiling or under ceiling air conditioning unit. Our Energy Recovery Ventilators are designed to work well with these and reduce the load requirements, thereby saving energy and money.
Is an ERV easy to install?
The Wall Mounted ERV comes apart in three sections for an easy one man installation job. This is low maintenance, with easy cleanable filters that are accessed from inside the room meaning that dusty areas aren’t a problem.
The In Ceiling ERV is installed in the ceiling space of a room, with fans and filters accessed from below for easy servicing. This is a slightly more expensive installation procedure, which is used when the school needs extreme quietness, with air noise less than 40 dba for the 300 l/s model suitable for most classrooms.
How can schools save money and use less energy?
Air Change Energy Recovery Ventilators were trialled in Queensland Schools. Excerpts from ‘Consideration of a novel air-conditioning technology for Qld Schools’ (December 2003) stated that "field and laboratory trials confirm the performance of the exchange media. In meeting AS 1668.2-1991, the ventilator regularly sheds approximately 10kWr while drawing only 130 watts."
Does IAQ affect student and teacher productivity?
Yes. It has been reported that for every 1-3% performance increase in productivity for very 10 L/s/p increase, which peaked in significance at 15 L/s/p but diminished to negligible effect by 45 L/s/p.
(Ecolibrium Magazine October 2008, p31)
"Children in classrooms with higher outdoor air ventilation rates tend to achieve higher scores on standardised tests in math and reading than children in poorly ventilated classrooms"
"Higher ventilation rates reduce transmission and spread of infectious agents in buildings"
Improved Academic Performance – Evidence from Scientific Literature – US Environmental Protection Agency: http://www.epa.gov.iaq/schools/student_performance/evidence.html
See Recommended Reading for further information.
What about the ‘open window’ policy?
The ‘open window’ policy for fresh air is not practical when outside conditions are extremely cold or hot. Indoor air quality will suffer due to heat, cold, dust, noise and other particles. During extreme climates, ventilation of a classroom using an energy recovery ventilator allows fresh air in for optimal indoor environment quality without affecting the indoor temperature.
Do you offer design assistance for large projects?
For multi classroom installations or large projects, we would recommend the appointment of a Consultant Engineer or Design & Construction firm to design and provide indicative costs for the project, write a specification and call for tenders from installation contractors. We can assist with contacts for engineers in your regions familiar with the requirements of schools.
Who can I contact for advice and more information?
You can call or e-mail the nearest Air Change State office or Distributor in the first instance.If you have a reliable installation firm you have used before, get them to call us to supply any technical information they may require.
Recommended Reading
To view articles and media specifically regarding educational facilities, please click here
Why Green our Schools on the Green Building Council of Australia web site shows the health and learning improvements from high indoor air quality and comfortable temperatures.