Hot tub water level drops

[6XSBChamps]

Just recently I’m noticing the water level in my hot tub is dropping about 1/2 overnight. I base the level on the spillover that it would normally be in line with. Is it possible I am noticing this now because I’m only running the pump a few hours a day and it’s off up to 20 consecutive hours and the hot tub being higher than my equipment pad means water from the HT is flowing back into the pump when off, until it reaches a certain level?
We’ve had some rain recently so I can’t get a good read on whether the pool as a whole is down water, but I really don’t think it is

 

[ajw22]

View attachment 463534
Is it possible I am noticing this now because I’m only running the pump a few hours a day and it’s off up to 20 consecutive hours and the hot tub being higher than my equipment pad means water from the HT is flowing back into the pump when off, until it reaches a certain level?

Yes.

Do you have a check valve in your SPA Return line?

 

[6XSBChamps]

Yes.

Do you have a check valve in your SPA Return line?

Yes?

 

[6XSBChamps]

Two? But I assume the one on the left is the one for the spa return

 

[6XSBChamps]

As I’m thinking about this I’m wondering if the check valve isn’t working properly because the temps dropped to low 40s and I’ve been running the pool only a few hours a day now. I assume the valve has a rubber component inside that hates that combo

 

[ajw22]

Yeah, that spa CV is probably leaking a bit.

It looks like you don't have automation and your POOL/SPA return valve is set to always run your spillover when in pool mode. In that case I would not worry too much about it as your spa will refill when your pump turns on.

 

[Toxophilite]

If you want to dig further, set your return valve to completely shut close spa return and monitor. I've had a tiny suspected water leakage finally show it's hand yesterday at the spa. Between the hot weather evaporation, fall weather evaporation, sporadic rains, etc... I could never nail it down as an actual water loss. Just knew something was amiss due to calcium loss rate. Days of straight rain has finally allowed pool water to seep up at pavers next to spa. I've shut the spa return off, and though it will take a few days of sitting with no refill, it's going to show my leakage level.

 

[6XSBChamps]

Yeah, that spa CV is probably leaking a bit.

It looks like you don't have automation and your POOL/SPA return valve is set to always run your spillover when in pool mode. In that case I would not worry too much about it as your spa will refill when your pump turns on.

Thanks. There is automation now, that’s an old pic but even with automation that valve is always set to that position for the spillway into the pool.

 

[6XSBChamps]

My bigger concern was that I had a leak in the plumbing somewhere that could turn into a bigger headache. But it sounds like that is not the case. Appreciate the replies.

 

[Toxophilite]

My bigger concern was that I had a leak in the plumbing somewhere that could turn into a bigger headache. But it sounds like that is not the case. Appreciate the replies.

Now that we have cooler weather and evaporation is slowed up, if you have an autofill, shut it off, then monitor your overall water loss. I have a feeling once I get my tiny leakage fixed, my 1/8" loss for this time of year (first year so no history), which I assumed normal, is going to dissapear to little to no loss.