No Check Valve - Should Jandy 3-way still allow back flow?

[SamanthaEstrello]

Hi All,

We have a Jandy No-Lube 3-way that splits the return water between the pool and the spa. The spa sits higher than the pool. There is no check valve on the return line to the spa. After the pump turns off, the Jandy allows water to back flow from the spa and back into the pool until the water level in the spa falls below the level of the return jets. Is the Jandy supposed to allow this to happen?

 

[Richard320]

Yes. You either need to close the spa off before the pump shuts off or install a check valve between the three way and the spa. It will let water flow into the spa but prevent it from siphoning down to the pool. Also note if you have both drains open, they'll siphon, too. I keep the spa drain normally closed and just let it fill and spill to keep the water in the spa fresh.

 

[SamanthaEstrello]

Thanks, Richard! That's what I thought, too.