Spa drains out water when pumps aren't running. HELP!

[cc517]

Fairly new pool owner and I just noticed for the past three days that when we wake up in the morning, the spa is drained of water almost completely into the pool. When the pumps turn on though, it refills back up. When I go look at the equipment (not knowing what to look for) I noticed that one of the valves (?) is constantly turning/rotatating when its in pool mode. If i switch to spa mode, it will move to the right direction and stop like its supposed to. But when I switch to pool mode, that valve keeps spinning and spinning. Does anyone know what could be the problem? Thanks so much for your help!

 

[JasonLion]

The valve actuator, device which turns the valve, is broken and needs to be replaced. There are small cams that rotate inside the actuator which are supposed to trigger switches to indicate that the actuator should stop turning. Either one of the cams or one of the switches is broken inside that actuator.

 

[mas985]

It could be as simple as a loose limit switch. If broken, some switches have part #s so you may be able to replace just the limit switch instead of the whole actuator.

 

[gary300]

The cams inside the actuator a pretty heavy duty, but the microswitches are fragile. I end up replacing the switches every couple of years. They are cheap and easily replaced.