How to Increase the Flushing Pressure on a Commercial Toilet
- 1). Unscrew the access cap located at the elbow where the water supply line enters the flush valve. This will expose the valve control stop screw.
- 2). Rotate the control stop screw counter-clockwise with a screwdriver until it is fully open. Rotate the control stop screw clockwise to fully close the valve.
- 3). Rotate the control stop screw counter-clockwise, one-quarter turn at a time. Test flush the toilet after each quarter turn of the screw to evaluate flushing pressure. Continue to open the control stop screw in one-quarter turn increments until adequate flushing volume and pressure is observed. Reinstall the access cap.
- 4). Check the building water pressure if adjusting the control stop screw does not produce adequate flushing pressure. Water supply specifications for a typical manual commercial toilet flush valve such as the Kohler K-13517 call for a static pressure of 35 pounds per square inch and a flow of 25 gallons per minute.
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