Plymovent Filters FAQs
Straight answers to the questions people ask most when choosing replacement filters for welding fume extraction systems.
Why should I avoid generic replacement filters?
A filter is a key part of the system's performance. A filter that differs in size, media or sealing can reduce airflow, let fume bypass the media, or stop automatic cleaning from working properly.
That can mean poor protection for people and damage to the unit. Use a filter specified for your unit unless the manufacturer confirms an alternative.
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.