Bohler Evolution Vision 65FM Air Parts FAQs
Answers on choosing, fitting and looking after the filters, lenses, comfort parts, battery and blower parts for a powered air welding helmet.
What does the filter cover do and how often should it be changed?
The filter cover holds a coarse pre-filter and usually acts as a first barrier against sparks and larger particles, which helps protect the main particle filter behind it. It takes the heaviest wear, so it is normally changed far more often than the main filter.
How often depends on the maker, the process, the material and how dusty the work area is. Some makers suggest changing a pre-filter once or twice a week in regular use, but follow your manual. Change it sooner if it is visibly dirty, clogged, damaged or burnt, and never run the blower without the covers and filters fitted.
How do I know the main particle filter needs replacing?
Common signs are a low-airflow alarm, a filter indicator showing it is spent, a much shorter battery run time than before, or visible damage or heavy contamination. A harder-to-breathe or weaker flow of air is also a warning.
HSE guidance says filters should be changed when damaged or visibly contaminated, and fan-assisted units should follow the manufacturer's instructions for changing them. Some makers also set a minimum change interval even if no alarm has sounded, so check your manual. If an alarm sounds, leave the work area and fix the cause before welding again.
Will a replacement particle filter protect me from welding gases?
Not necessarily. A particle filter is designed to remove fume and dust, and HSE notes that P3 particle filters do not protect against the gases that can be present in welding fume. If a gas or odour filter is fitted to your blower, it must be one the maker specifies for that unit.
If you notice a smell, irritation or taste while welding, treat it as a sign that exposure is not under control. Stop and review your ventilation and respiratory protection with your employer or safety adviser. Do not rely on smell as a way of judging when a filter is used up.
When is a blower motor unit the problem rather than the filter?
A blower motor draws air through the filter and passes it to the helmet. If the flow is low even with a fresh filter, a fully charged battery and a clear, undamaged hose, the fault may lie with the motor, the seals or the electronics.
Before you suspect the motor, rule out the simple causes: a blocked cover, a kinked or loose hose, a missing seal, a tired battery. Anything beyond cleaning and part swaps should be done by a competent person following the manufacturer's instructions, because HSE advises that more intricate repairs are not a job for the wearer. Test the airflow again after any repair.