Raised Spa Leaking Overnight With Pump Off

[fourtitude]

I resolved a raised spa leak about 4 months ago that was draining overnight with the pump off by replacing the check valve, but the problem appears to have come back. Raised spa loses about 1 - 1.5 inches overnight (sometimes less if not at all). What's odd is that I measured the pool level and it didn't seem to rise, assuming it is related to another bad check valve.

I opened up the spa check valve I replaced last year and it looked good. There is another one for the spa water feature that I haven't opened. I've currently turned off all return to the spa while the pool continues to be filtered so I can see how far down it drains. I had the system completely turned off for 24 hours and when I turned on the pump to the pool, bubbles were coming out of the jets for about 30 seconds (not sure if this is normal).

A couple of questions:
- Would to pool raise in level if an inch of water flowed back from the spa, assuming a 600-700 gallon spa with 18,000 pool?
- Any ideas on what else it could be? Don't know if it's too premature to call out a leak detection company.

Attached are images of the spa indicating the drop in level and the plumbing. This drop occurred over a 18 hour period with the pump off.

 

[mas985]

The pool level would change by the ratio of the two areas. So it would be much less than the spa change. For example, if the spa was 50 sq-ft and the pool is 500 sq-ft, a 1" change in the spa relates to a 0.1" change in the pool. So it may not be easy to detect.

A raised spa will usually have check valves on both the suction and return. You need to make sure both are in good condition. Also, it looks like they plumbed in a bypass which has it's own check valve so you need to check that one too.

Air out of the spa jets could just be a symptom of the valve leakage. The venturi vent breaks the vacuum so some air may get into the lines as water flows from the spa to the pool.

 

[fourtitude]

Thanks for clarifying about the pool level and air bubbles.

I don't see any check valve on the spa suction side (just the 1 on the spa and another on the spa water feature), just the jandy actuator valve feeding the filter pump. Could it possibly be a leak with this valve on suction side? I did the test of running the spa for 30 minutes and the level didn't decrease. Right now I have all valves to the spa closed and just running the pool pump trying to determine where the problem may be.

 

[mas985]

Yes, the regular spa/pool valve can also leak and another thing to check.

Just one more question. When the spa level drops, does it reach the pool level and stop or does stop above/below pool level? The later could indicate an external leak.

 

[fourtitude]

Thanks again. Don't know yet about the spa level drop since it is slow and only drops about an 1-2 inches over 18 hours before the pump kicks back on. I'm currently turning off the spa over the next couple of days to determine if it could be an external leak which I'm hoping it's not. Will keep you posted.

 

[fourtitude]

Quick Update: I put the pool in spa mode and left it overnight and the spa still draining about 1 inch in 18 hours. Thoughts?

 

[mas985]

It is either a 3-way valve leak or it is an external leak. Did you detect a rise in the pool level? I would take apart and inspect the 3-way valves just to make sure. You also have a bypass so you need to check the valves in that loop.

 

[fourtitude]

I didn't detect a rise in the pool level, since it's only about an inch of water leaving the hot tub. I'm hoping for the best that it isn't an external leak. How difficult is it to check the 3 way valves and determine there is a leak in the valve? Still holding off on getting someone to look at.

Thanks!

 

[fourtitude]

One thing I just noticed that when I set the mode to spa drain, the actuator on the suction 3 way valve turned 3 times around and the valve wasn't quite in the fully off position. Next time I put it in spa drain mode, it kept turning and didn't stop after 10 minutes. Could be something faulty in this valve? Another thing I just noticed was a small drip from the end of the backwash tube, but not sure if this could cause the spa level to fall.

 

[mas985]

Definitely. The valve actuator has a stop which dictates where the valve stops. If it is going around a couple times, the stop is not in the correct location. You need to open the actuator and adjust the stop which is a small switch.

 

[fourtitude]

Thanks for the awesome diagram! Mine is a little different (JVA 2444), but concept is the same. I noticed that the lower micro switch sometimes isn't activated which is causing it to keep spinning. Maybe a bad switch? Still don't know if the bad actuator is related to the spa leak since I haven't moved it to spa mode in a while, but for now I've closed off all drains and returns to see if the spa level changes.

So far I haven't see any drainage, but should know more in a couple of hours. If it holds up, it's most likely related to the suction valve and/or actuator.

 

[imperator]

A raised spa will usually have check valves on both the suction and return. You need to make sure both are in good condition. Also, it looks like they plumbed in a bypass which has it's own check valve so you need to check that one too.
.

What would the suction side chk valve do for the raised spa?

 

[mas985]

The picture doesn't show the suction side so I was speculating some. But given the return side plumbing, the spa would still drain when in full spillover mode (i.e. spa return valve on, pool suction on). To prevent this, sometimes a pool side suction valve is used. Also, some PBs will put in a suction side check valve just to prevent the spa from draining while the valve is switching. This also helps in priming when the pad is significantly elevated. To simplify things I would have moved the bypass check valve to the common pipe going to the spa so it would have prevented back flow in spillover and bypass modes.