The pressure gauge reading, with clean HEPA filters is about 1.8”-2.0” WC, The HEPA filter will need to be replaced when
the pressure gauge reads 3.5” WC with a clean primary/secondary filter.
During your projects, your HEPA filter purifies the air and gradually becomes loaded with sub-micron particulates.
Even when the HEPA filter is fully loaded, the filter is still removing particulates from the air at the rated efficiency yet, at
a reduced airflow. This will affect the ability of the machine to provide positive or negative
pressure within the containment.
To replace the HEPA filter, turn the blower unit OFF. Open the door and remove the pre-
filter. You will see 4 filter tabs holding the HEPA filter in place (see photo). These tabs are
secured with 1/4-20 Nylock nuts, which require a 7/16” wrench or socket. Remove all (4)
filter tab retaining nuts, remove the filter and set aside. Slide the HEPA filter out along the
filter guides and remove it from the machine. ALWAYS TREAT THE USED HEPA FILTER AS
HAZMAT AND PROCESS IT ACCORDING TO YOUR ESTABLISHED HAZMAT PROCEDURES.
To replace the HEPA filter, ensure that the gasket on the HEPA filter faces inward toward
the flange, slide the filter in place along the filter guides and re-install the filter tabs and filter tab securing nuts. The
nuts should initially be tightened to where the stud is flush with the end of the nut. This will compress the gasket on the
filter approximately 1/2 of the thickness. This allows for the filter to be reseated and tightened later if necessary.
Bag Filter Replacement (if used)
The bag filter housing can be installed in the place of the HEPA filter using the filter tabs and nylock nuts. The bag filter
is secured inside the housing with (4) P-clips. To remove the filter, turn the P-clips 90 degrees and pull it out. Then install
the new bag filter and secure it using the P-clips.
Please note the bag filters have a large dust holding capacity and require replacement when the airflow of the
machine drops below required minimum flow or the DP gauge reaches 3.5” WC. Even when the filter is fully loaded, it
is still removing the particulates from the air at the rated efficiency but at a reduced airflow. Typically bag filters do not
require the use of prefilters.
Vapor Trap Filters
Activated carbon filters are designed to remove odors and gaseous pollutants from air. These filters are an effective
and quick solution to your VOC’s and odor problems. The selection of the carbon filter depends on the type and
amount of the gaseous pollutants. You will need to determine the requirements of your application. The Vapor Trap is
a disposable V-Bank, 24”x24”x12” filter and contains 36lb of activated granular carbon. It can be installed in place of a
HEPA filter. We recommend using our primary/secondary filter in front of the Vapor Trap to extend its odor absorption
capacity.
filter tab
