Pool set to recirculate, but sending water out of waste?

[BroomePool]

Hey guys, I was using the Recirculate setting on my inground pool and noticed that it was also sending a little bit of water out the waste pipe as well as sending water through the return pipe. I've never used this setting before, but I'm not sure that's supposed to happen. Is there something wrong with it?

[TSH Tech]

Recirculate is a setting that bypasses the filter and shoots unfiltered water back into the pool. This setting is actually helpful when using water clarifying chemicals such as flocculants.

I'm going to assume this is a sand filter backwash valve? A circular type?

Yes, when water starts coming out the waste pipe despite the selector position, that means the rubber seals inside of it have worn, crushed or disintegrated and needs to be replaced. In the pool industry, we call it the "Spider gasket", but to the bookworms behind the counter, it's known as the "Backwash Valve Multiport Gasket"