These pond pumps are able to be used in an in-line flooded suction installation. They can be mounted externally from the pond but for this application they must always stay in prime when switched off. Their design allows the pump to be used either submersed or in-line. Pond pumps rely on water flowing through them for cooling.
Important limitations when used in-line:
- The pump must never be allowed to get air inside the tubing or pump chamber.
- It must be located below water level externally to allow constant flooded suction whether switched on or off.
- The pump must never be allowed to lose water charge or prime when switched off for risk of damage from overheating when later switched back on.
- The reliance of a non-return valve or check valve to maintain prime or charge is very risky.
- These pumps are not positive displacement pumps like swimming pool pumps and so will not draw air up the pipe.