Air leak?

[Nitramnayr]

Our main pump can filter our spa or divert its suction to filter pool.

Water runs in and out of the heater regardless of which side is being filtered.

The RPM for the spa is set to the same as the pool RPM.

The filter basket is noticeably emptier when the Spa is being filtered. I can hear bubbles/popping by the heater inlet/outlet (bottom of the photo) when the spa is filtered, but not when the pool is being filtered.

I changed 2 o-rings on the powered diverted valves that were smashed in one spot and thought that would help. Apparently not.

Any guesses where I should focus my efforts for a suction leak?

 

[PoolGate]

Try running the hose over all the connections if you find the leak while the hose is running the pump basket will fill.

 

[Nitramnayr]

Try running the hose over all the connections if you find the leak while the hose is running the pump basket will fill.

I tried that and burning incense on a calm day. Didn’t seem to have luck with either. Is there maybe a valve inside the heater that could have an air leak?

 

[HermanTX]

When in spa mode, does your return line to the spa draw air in to make bubbles? Or do you have a air blower that is powered on or off? Are you seeing more bubbles than usual being returned to the spa?

 

[wireform]

Hard to tell from the picture but it looks like the suction line of the cleaner pump comes off the spa side of the diverter valve which would mean when set to pool the cleaner suction has no access which would also mean if it were letting in air it could only happen when the valve is set to spa. That may be where you're getting the air leak from. Check all three cleaner pump connections.

 

[Nitramnayr]

When in spa mode, does your return line to the spa draw air in to make bubbles? Or do you have a air blower that is powered on or off? Are you seeing more bubbles than usual being returned to the spa?

We have a separate air blower but I haven’t turned it in in a few weeks. There is also a check valve for the spa water to maintain its level once the pumps shut off since the spa sits higher than the pool, but the bubble sound seems to come from the heater which is plumbed prior to the check valve.

The bubbles in the spa are micro bubbles that almost make it cloudy.

 

[Nitramnayr]

Hard to tell from the picture but it looks like the suction line of the cleaner pump comes off the spa side of the diverter valve which would mean when set to pool the cleaner suction has no access which would also mean if it were letting in air it could only happen when the valve is set to spa. That may be where you're getting the air leak from. Check all three cleaner pump connections.

Will check them out, thank you

 

[Nitramnayr]

Hard to tell from the picture but it looks like the suction line of the cleaner pump comes off the spa side of the diverter valve which would mean when set to pool the cleaner suction has no access which would also mean if it were letting in air it could only happen when the valve is set to spa. That may be where you're getting the air leak from. Check all three cleaner pump connections.

Yes it’s not a great photo- sorry. The cleaner suction and return lines by the pump connect to fittings in the ground, presumably to the wall connector.

The water level in the spa/pool pump is near perfectly full (small air bubble) when the pool side is filtering. When the spa side runs it drops considerably.

 

[wireform]

More pictures from different angles can only be beneficial in solving your issue.

 

[HermanTX]

Do you occasionally bleed the trapped air in your filter? That ensures your filter is full of water for best filtering efficiency and also reduces any air that may be pushed to your returns. That does not solve your issue with the pump water level being low when in spa mode but just a good practice to remove air in the system.

It does appear you could be drawing air into your spa suction from an underground leak.
Additional views of your equipment pad will help rule out any other potential leak paths.

Question - on your filter exit pipe it (labelled filter return) goes to a manual 3-way valve. One pipe goes to the heater, where does the other pipe go to? Is this part of a heater bypass setup?

 

[Nitramnayr]

Do you occasionally bleed the trapped air in your filter? That ensures your filter is full of water for best filtering efficiency and also reduces any air that may be pushed to your returns. That does not solve your issue with the pump water level being low when in spa mode but just a good practice to remove air in the system.

It does appear you could be drawing air into your spa suction from an underground leak.
Additional views of your equipment pad will help rule out any other potential leak paths.

Question - on your filter exit pipe it (labelled filter return) goes to a manual 3-way valve. One pipe goes to the heater, where does the other pipe go to? Is this part of a heater bypass setup?

I have recently been bleeding the filter air when emptying the basket but will keep this habit going forward- thank you.

Here are a few more photos. The first one has a single drop and I am going to check it in the morning to see if it was caused by me bleeding the air from the filter just now or if it’s the culprit. I think it may be the culprit based on its location.

I believe you’re asking about the valve that bypasses or feeds rhe UV light? I did change rhe o-ring in it recently.

Thanks again-

 

[RDspaguy]

Air in your pump basket while running the spa but not while running the pool either means your air is entering from the spa suction pipes. It will end up going through, building up in your filter and heater, before returning to the spa. Or it is a flow restriction when in spa mode. Cavitation in the pump will produce an air pocket.
I would start by playing with the valves. Turn it to return to the pool and draw from the spa, then draw from the pool and return to the spa, and see what it does. This should at least isolate the issue and give us a clue where to look next.
Also, if your air control valves are open and the lower jets are blowing bubbles in front of a suction fitting it will catch air there.

 

[Nitramnayr]

We are getting warmer. I switched the diverter valve that RDSpaGuy mentioned above. Bubbles definitely forming when suction to spa is active. I’m cleaning the valve again and am guessing it’s either a crack in the valve, the elbow running down into the ground, or an underground leak. Wouldn’t it be pulling in mud/silt though if it were underground? I do not know where the spa suction line terminates. Presumably by tying into the spa drain?

 

[Nitramnayr]

I lubed o-rings in diverter valve. Seems to help a little. While pump was running I moved the UV bypass valve and heard a bunch of air clear out. Should this valve (laying flat, in the rocks) be open to help decrease air bubble formation, or will it make things like the UV less effective?

 

[Rancho Cost-a-Lotta]

Wrap the spa suction elbow and joints (before the valve) tightly with Saran Wrap and see if it makes a difference.

 

[PoolGate]

I lubed o-rings in diverter valve. Seems to help a little. While pump was running I moved the UV bypass valve and heard a bunch of air clear out. Should this valve (laying flat, in the rocks) be open to help decrease air bubble formation, or will it make things like the UV less effective?

FYI: UV does nothing for an outdoor pool. You get many times more free UV from the sun. The miniscule output of the UV lamp only works on water that passes through it anyway and that UV bulb will wear out enough in about a season as to lose what little value it may have held. The good news is that it doesn't hurt anything but your wallet and most people can't tell whether it is working or not.

 

[Nitramnayr]

Good news- turns out it was the check valve that had a bad seal. Replaced it and neither spa nor pool has much air in the basket. Thank you all for your help solving the mystery!