Leak when pump is running in filter position

[Traulz]

OK, first let me start by saying thank you so much to all of you, because without you I would've never even been able to start anywhere on this pool. Secondly please bear with me, because I'm gonna ask some really dumb questions, does even know over the past four months, I feel like I have become a somewhat pool connoisseur, I still have stupid questions. With that being said, I have noticed that I am losing an extreme amount of water, when the filter is running on the pool in the filter position. I have checked all my lines, I have made sure that all my seals are tight, and I'm still losing water. Now I've narrowed it down to, most likely losing water in the backwash line, and I'm assuming it's probably because of the spider valve gasket. But before I take everything apart, I had just a basic question. When my pool pump is running in the filter position, will I see water running through the sightglass on the backwash line? I guess what I'm trying to figure out is should there be water through the sightglass on the backwash line if my pump is running in the filter position? I'm assuming if I'm not supposed to see that, then I am losing water there. Any help would be appreciated, and thanks in advance.

 

[duraleigh]

How much water are you losing? Where does the backwash line go?

 

[Traulz]

The backwash line runs underground, and I'm losing probably about 3 to 4 inches, every two hours.

 

[Traulz]

That's why am asking about the sightglass question, because I can't see if I'm losing water in the backwash line, as it runs underground.

 

[JamesW]

Unscrew the sightglass and listen for the sound of a leak with the pump on and then with the pump off.

You might want to put a union in the waste line to give you the ability to check for a leak.

Do you know where the end of the waste line is?

You can't see a small leak out of the waste line by looking at the sightglass.

You can cut the waste line to see if water is leaking. You can use duct tape to temporarily seal the line.

 

[Traulz]

Thanks James, I definitely will try these things. No, I cannot see where the waste line ends, I guess that's why I was asking when your pump is running in the filter position is there supposed to be water showing up in the sightglass.

 

[JamesW]

Water gets trapped in the sightglass when you use backwash, rinse or waste.

I would cut the line to check. When you replumb, add a union and T for a vacuum breaker. You can get a vacuum breaker at any hardware store.

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