Differential and LEV Hood Pressure Gauges for Ventilation System Performance

Filter differential pressure gauges and captor hood pressure gauges enable operators to clearly see operating parameters of the extraction/ventilation system.

  • Filter differential pressure gauges enables easy identification of when filters require cleaning or changing, or can indicate blockage or filter failing.
  • Gauges marked with normal operating range for specific filter and / or cleaning system type.
  • Pressure gauges fitted with a static pressure spigot provide a quick and simple method of determining ventilation system / captor hood performance:

An increase or a decrease from the ‘normal operating range’ can indicate that further investigation is required, for instance:

  • An increase in pressure can indicate a blockage ‘upstream’ of monitoring point ie at air grill, or ventilation hood. Or a blockage in stack, i.e. on exhaust side of fan.
  • A decrease in pressure can indicate a blockage ‘downstream’ of monitoring point for instance blocked filters, fan impellor damaged or impaired etc.

DF001 pressure gauge

Filter Magnahelic Differential Pressure (D.P) Gauge Operation (Dust extractor Unit)

Magnahelic D.P gauges fitted across filters provide a quick and simple method of determining filter/extractor/LEV condition: 


Pressure Gauge

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  1. Indicates that the extractor is not running or dust may have blocked the pressure spigot fitted to the extractor. It can also indicate that the filters have failed i.e. dirty air is bypassing the filters either through a hole in the media, or through the cell plate seals.
  1. The area marked in green is the normal operating range of the filters. Typically you should expect the needle to rise gradually over the life of the filters.
  1. At this point, the resistance generated by the filters will begin to impede the performance of the extract system. It will be necessary to run the cleaning system more often to return the needle back into the green zone. New filters will need to be fitted when the needle will not return to the green operating range regardless of cleaning frequency/duration.



We carry out project and ventilation works in the following areas: Hampshire Berkshire Avonmouth Dorset Devon Wiltshire Somerset Oxfordshire Buckinghamshire Middlesex Northamptonshire Surrey Sussex Wales Bedfordshire Gwent Cambridgeshire Cardiff Carmarthenshire Ceredigion Clackmannanshire Derbyshire Essex Gloucestershire Greater London Gwynedd, Hertfordshire, Isle of Wight Nottinghamshire Kent Leicestershire.