How to install a check valve: orientation, distance from pumps, common mistakes
A check valve only works properly when installed correctly. Wrong orientation or a position too close to the pump leads to disc flutter, wear and slamming.
TAZ Engineering Team · · 5 min
Flow direction
Every check valve body carries a flow arrow. Installing it backwards is a common repair mistake that simply blocks the line.
Pipe orientation
Swing checks go on horizontal lines with the cover up and on vertical lines with upward flow; downward flow is not acceptable for most swing checks. Lift checks normally go on horizontal pipe only unless the manufacturer allows otherwise. Spring-assisted and dual-plate checks accept more positions; check the datasheet.
Distance from pumps and fittings
Flow straight after a pump, elbow or reducer is uneven and swirling, so the disc flutters and knocks. Provide a straight run upstream, typically several pipe diameters; the valve manufacturer gives the exact figure.
Maintenance
Install isolation valves either side of the check valve so it can be removed or opened without draining the system, keep the cover accessible and inspect the hinge pin and seat periodically.
Checklist
- flow arrow
- pipe orientation
- cover up
- upstream straight run
- isolation either side
- maintenance access