Plymovent Filters FAQs
Straight answers to the questions people ask most when choosing replacement filters for welding fume extraction systems.
How do I choose the correct replacement filter for my extraction unit?
Use the unit's data plate and manual to identify the exact filter type and size. Filters vary in shape, media, surface area and sealing method, and units are designed around a specific filter.
Never choose by appearance alone. Note the filter's reference and dimensions from the old one, and ask our team if you cannot identify it.
How do I know when a filter needs replacing?
Most units have a pollution indicator or pressure gauge that shows when the filter is loaded. Other signs are weaker suction at the hood, more frequent cleaning cycles, and more dust or smell in the workshop.
Change the filter when the indicator says so or if airflow cannot be restored by cleaning. Keep a record of change dates to help plan.
What does a pre-filter do?
A pre-filter catches larger particles before they reach the main filter, so the main filter lasts longer. Some pre-filter stages also help reduce the chance of sparks reaching the main filter, but only if the maker designed them for that purpose.
Pre-filters are normally quicker to change than main filters and may need cleaning or replacing more often. Check the manual for your own unit for the type to use and how often to check it.
What is an activated carbon filter used for?
It adsorbs gases, vapours and odours that ordinary particle filters cannot catch, for example from some solvents, coatings or certain processes. It is usually an additional stage after a particle filter.
Carbon filters become saturated and need replacing on a schedule based on the contaminants and use. They do not trap solid fume particles.