Most paint booths come with a manometer mounted on a rear side near the filter bank. It measures in inches of water the pressure differential between the front and back of the filters. As build-up occurs, pressure increases. The manometer can help determine when it is time to change the filters, which can increase the effectiveness of a paint booth. Unfortunately, many painters don’t use and maintain them or don’t even know their purpose.
How is a Manometer Calibrated and Used?
- Replace all filters in the paint spray booth and make sure there are no gaps between the filters and the holding frames.
- Read the manometer while the blower is turned off. It should read zero. If not, recalibrate to zero by turning fluid adjust knob. Put red dye in the water so it is easier to see.
- Close the doors of the spray booth and start the blower. Wait until the level in the manometer stabilizes and mark this “starting” level.
- As a general rule, most filters should be replaced when the manometer level is 1” above the starting level. Mark this spot and exactly 1″ higher than the starting mark. For example, if the starting mark is at 0.25″ place the final mark at 1.25″