Air filtration is used in a wide variety of situations, from heating and air conditioning in offices to extraction systems in factories and workshops. One of the most important aspects of making sure these HVAC systems work efficiently is ensuring that the filters are cleaned or changed on a regular basis.
Poor air quality is a major problem; in fact, it is estimated that it is responsible for one in nine of all deaths worldwide. Making sure that the filters of your HVAC system are changed regularly is therefore vitally important.
The difficulty is that filters tend to be out of sight and out of mind. Air is delivered through a spiral duct and many people may not realise that there is a problem until they see dust or particles blowing out of their vents.
Types of filter
Air filters come in different types. Washable filters are usually made of cloth or metal that can be cleaned and reused multiple times. Other types of filter include fibreglass and polyester types with fibres sandwiched between a grille, which are designed to be disposable.
Some systems use HEPA (high-efficiency particulate air) filters, which are designed to catch over 99 per cent of particulates greater than 0.3 microns – smaller than the thickness of a human hair. A high-performance filter traps more, so it is likely to need changing more often. The dirtier your environment, the harder your filters will work, so when should they be changed?
Time to change
An increase in staff suffering allergies or having breathing problems is likely to be a sign that your filters are clogged. This will also have the effect of reducing airflow in your spiral duct, exacerbating the problem further.
A way to test your filters is to hang a white cloth in front of one of the outlet grilles for an hour or so. If it gets covered in grey or black particles, it is time to change the filter. Another sign of a clogged filter could be that the system fans are having to work harder and you may notice an increase in noise or a jump in your electricity bill. If your filters are easily accessible, a simple visual check for dust and fluff may be enough to tell you that it is time to change them.