- The G99 Generalaire Air Filter Gauge provides a visual indication of the need to replace air filters in forced air heating and cooling systems.
- The gauge is installed between the blower and the air filter where a slight vacuum exists due to the air flow resistance of the air filter.
- Air flowing into the gauge, around the calibration screw, lifts a vane in proportion to the negative pressure in the blower compartment.
- As the air filter loads (gets dirty) the vacuum increases, raising the vane of the gauge to indicate a filter change is needed.
- The G99 Generalaire Air Filter Gauge measures 2 3/16″ X 2 3/16″ Comes with installation instructions.
- Please click on the following link if you would like to see the a PDF instruction sheet: G99-air-filter-gauge-instructions
- *Same Business Day Fast Shipping!
- Please email us anytime if you have a question. Our email address is: firstname.lastname@example.org
- We would love to help you out and have your business!