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Inline Filter Box

What is a filter box?

Filter boxes are used for air filtration in ventilation and air conditioning systems. Where a ductwork installation requires air to be filtered, removing contaminants from the airflow through a ventilation system. The in-line filter box prevents entry of dust and other contaminants from reaching fans, motors, heat exchangers or areas being ventilated.

The filter media is mounted inside galvanized steel housing (box). The in-line duct filter boxes have easy to open covers with convenient quick release clips, enabling a quick and easy change of filter elements. Our standard ducting filter boxes are available to fit spiral duct sizes from 100mm to 560mm diameter with the option of either EU3 or G4 filter media available to suit, one filter is supplied with the purchase of a filter box as standard. 

How do filter boxes work?

In-line filter boxes can be mounted at any point in a duct run between spiral ducts. The filter box has a male end spigot on either side which fit into the spiral ducting (female end). Extracted air travels through the duct run and reaches the air filter box hvac where it passes through a panel type filter. These filters remove contaminants from travelling further through the duct work, preventing them from reaching fans, coils, heating coils, and areas being ventilated. 

Spare filters for your duct filter box

Ducting Express offer a large range of replacement filters to suit your duct mounted filter box. These disposable filters sit inside an inline filter box fitted in your duct run. Both EU3 and G4 filter media are available. 

EU3 Filter Media - These panel filters are medium level efficiency disposable air filters, often used as pre-filtration. This type of filter media is commonly used in simple ventilation for garages & factories.

G4 Filter Media - A pleated panel air filter is a medium efficiency disposable air filter, suitable for ventilation and air conditioning systems which require a higher efficiency and greater dust holding capacity than can be achieved with glass or synthetic panels. They are typically used as pre-filters on supply air systems to high performance bag filters, or to protect heating or cooling coils from dust build up which leads to system inefficiency. Another common place to see a G4 Pleated Panel Air Filter is to protect fans in extract systems for office blocks or kitchen extract systems.

How often should I change my HVAC air filters?

All filters need replacing and should be checked regularly. Filter life depends on the amount of particulate being captured. 

If panel type filters are not properly attended to, they can easily become clogged and in turn preventing air flow. This loss of airflow can sometimes cause the system to overheat and could, over-time, lead to equipment breakdown or even fires. Changing the filters in your air duct filter box regularly is crucial for health & safety and a HVAC systems longevity.

Still wanting some further information? Give our team a call on 01455 616 444 today, our experienced staff can help to advise the most suitable duct filter box option for your installation.