Dirt Pumped Into Pool When Switching On Pump - Sand Filter System

by Pat

Dirt Pumped Into Pool When Switching On Pump - Sand Filter System

by Patrick J
(South Africa)

When the pool pump is turned off there is a loss of pressure and water returns to the pool from the filter. When the pool pump is switched back on there is air in the system and the pump has to be re-primed, then there is air pumped into the pool with a great deal of turbulence.

This is followed by a stream of dirt which eventually clears and the system then functions normally until the next cycle when the scenario is repeated. The result is the pool never clears properly and dirt settles on the floor where the Kreepy Crawly doesn't go. What would be the cause?

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Thanks for the question Patrick

When dirt enters the pool through the returns with a sand filter, it could be the following:

1. Broken lateral
2. Too much or too little pool sand media
3. Channeling

More times than not it's a broken lateral. You might need to scoop out the sand and replace the lateral(s).

For the loss of prime I would check the obvious first:

1. Bad, old, or broken Multi-port Valve. Check the gasket or O-ring. Turn the pump off and switch valve positions. If it doesn't "click" nicely in place you may need to replace it.

2. Gasket around the pool pump motor lid. If broken or worn replace it.

3. Look for obvious wet spots on and around the filter and ground. You might have a leak that is drawing in air.

4. The return line(s) might be cracked. Easy way to find which line is with the pump running, open the skimmer valve all the way and close the main drain valve. If there's a loss of suction the problem is the skimmer line.

Close the skimmer valve and open the drain valve. Again if there's loss of suction, it's the drain.

5. With the pump off check the pump motor impeller
for clogs or debris. Be sure the keep the pump basket and skimmer basket clean.

6. There is also the mechanical seal in the pump motor. A mechanical seal is a seal which helps join systems or mechanisms together by preventing leakage. I've replaced a few of these on the pool pump motors at the YMCA when we've had a leak, but the motors run 24/7.

Hope this helps and let me know how it turns out for you