Spa Overflowing


New member
Nov 9, 2014
I have a in ground pool and spa which are separated. When I turn on the pump the spa overflows. I looked at the equipment and there is a shutoff valve and check valve between the pool and spa return lines. The flow direction on the check valve goes from pool to spa. I turned the valve to the off position and the spa stops overflowing. Just up stream of these return lines is a Jandy 3 way valve and actuator. The person at my local pool store said it sounds like the 3 way valve is bad. This does not seem to explain why the problem stops when I turn the manual valve off. So to me it seems to make sense if I prevent water from flowing into the spa it would not overfill - is there another line that would allow the spa water to get back over to the pool? Appreciate any ideas.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
Welcome to TFP!

There kind of has to be an overflow, that lets excess water in the spa go back to the pool. However, it presumably can't handle the full output of the pump.

There are two valves with actuators. One chooses where the pump draws water from, pool, spa, or both. The other chooses where water from the pump goes, pool, spa, or both. For the spa to overflow, all of the water from the pump must be going to the spa, but the pump must be drawing water from the pool, or perhaps both the pool and spa. That means more water going to the spa than is taken from the spa, so it overflows.