59
Donaldson Company, Inc.
Optional Equipment
Magnehelic
®
Gauge
The Magnehelic is a differential pressure gauge used to
measure the pressure difference between the clean-air and
dirty-air plenums and provides a visual display of filter change
requirements. The high-pressure tap is located in the dirty-air
plenum and the low-pressure tap is located in the clean-air
plenum.
1. Choose a convenient, accessible location on or near
the collector for mounting that provides the best visual
advantage.
2. Plug the pressure ports on the back of the gauge using
two, 1/8-in NPT pipe plugs supplied. Install two, 1/8-in
NPT male adapters supplied with the gauge into the high-
and low-pressure ports on the side of the gauges.
3. Attach the mounting bracket using three, #6-32 x 1/4-in
screws supplied.
4. Mount the gauge and bracket assembly to the supporting
structure using two, self-drilling screws.
5. Thirty-five feet of plastic tubing is supplied and must be
cut in two sections. Connect one section of tubing from the
gauge’s high-pressure port to the pressure fitting located
in the dirty-air plenum. Connect remaining tubing from
the gauge’s low-pressure port to the fitting in the clean-
air plenum. Additional tubing can be ordered from your
representative.
6. Zero and maintain the gauge as directed in the
manufacturer’s Operating and Maintenance Instructions
provided.
1/8-in NPT x 90°
male elbow
clean-air plenum pressure
tap location
1/8-in NPT adapter
1/8-in NPT adapter
plenum tap location
3/8-in flat washer
1/8-in NPT coupling
mounting bracket
#6-32 x 1/4-in mounting screws
support structure
mounting surface
Magnehelic gauge
high-pressure port
low-pressure port
two, 1/8-in NPT
adapters
plastic tubing
two, 1/8-in NPT pipe plugs
two, self-drilling screws
1/8-in NPT x 90° male elbow
dirty-air plenum pressure tap location
3/8-in flat washer
1/8-in NPT adapter
1/8-in NPT x 90° elbow
static pressure tee
Magnehelic Gauge Installation
