Air in the pump basket - suction side leak?

[ashg]

Hey folks,

I've got a recent issue that I could do some help with - I just redid my entire pool pad with new equipment and I hope I didn't, errr, mess up.

At low RPM, I'm getting air in my pump basket -prob 1/5 the depth of the basket. At max RPM, I'm getting loads of bubbles wizzing around - this air is making its way to my filter.

The problem persists if I have the spa main drain on, or I switch to any of the other 4 pool drains/vacumm/skimmers.

A few pics on my new setup:




What I have done:

1. Lubed 2 x bottom valves on pump
2. Lubed pump lid oring
3. Lubed both union connections.
4. Checked 3 way diverter value - oring lubbed and I've checked the depth of the PVC weld
5. Checked all 2 way diverter valves - oring rubbed and I've checked the depth of the PVC weld
6. Used a hose to pour slow water over each connection - no change in air
7. Used shaving cream over each connection/valve - no identifiers.

I am at a loss! Could the air be coming in from after the water leaves the pump or is this defo a suction side leak? Given I see the effects with the diverter value in both directions, this indicates it's the line coming into the pump, but I can see no evidence of it.

Any ideas of what to try next?

Thanks!

 

[PoolStored]

1. Lubed 2 x bottom valves on pump

Do you mean the drain plugs on the pump?

Air is coming from the suction side.

What are the 5 sources?

I would isolate every line and run each separately to see if you can identify one line that is the cause.

1. Top diverter as it is set.
   1. Turn off three of the diverters, leaving one pipe open.
   2. Open a second diverter and close the first one.
   3. Continue until you have checked all 4 lines.
   4. DO NOT CLOSE ALL 4 VALVES at once.
2. Turn top valve 180 degrees.

If the bubbles are coming from only one line, then the air source is past the valves in that line.
If the bubbles continue independent of diverter selected, your source is at one of the diverter or after the diverter.

 

[ashg]

Do you mean the drain plugs on the pump?

Air is coming from the suction side.

What are the 5 sources?

I would isolate every line and run each separately to see if you can identify one line that is the cause.

1. Top diverter as it is set.
   1. Turn off three of the diverters, leaving one pipe open.
   2. Open a second diverter and close the first one.
   3. Continue until you have checked all 4 lines.
   4. DO NOT CLOSE ALL 4 VALVES at once.
2. Turn top valve 180 degrees.

If the bubbles are coming from only one line, then the air source is past the valves in that line.
If the bubbles continue independent of diverter selected, your source is at one of the diverter or after the diverter.

Thanks!

So the air is independent of all 4 diverters - and will actually create a deep air bubble if just 1 is selected. At max speed, with three open you will see lots of little bubbles, but just one, it will be a large air void? Does that make sense?

 

[PoolStored]

So the air is independent of all 4 diverters - and will actually create a deep air bubble if just 1 is selected. At max speed, with three open you will see lots of little bubbles, but just one, it will be a large air void? Does that make sense?

No it doesn't make sense.

I'm trying to help determine where the leak is.

You have two inputs. On on the left and one on the right. The top valve allows you to choose the right or the left. The one on the right has 4 that come into 1.

By closing every other input but one, that isolates the suction to that pipe. If you are seeing air from only one of the 5 pipes coming out of the ground, when you have the other 4 closed, then you have a leak in that pipe.

If you continue to get air during this testing, that means that leak is likely between the diverters and the pump.

 

[mas985]

Thanks!

So the air is independent of all 4 diverters - and will actually create a deep air bubble if just 1 is selected. At max speed, with three open you will see lots of little bubbles, but just one, it will be a large air void? Does that make sense?

When you close off more suction valves, the suction inside the pump basket becomes higher (i.e. lower absolute pressure) so it is more likely to leak air. Also, the pump flow rate decreases so it is less likely to purge any air that might get into the pump basket so it will accumulate more.

Have you checked pump lid gasket for cracks?

 

[ashg]

Thanks both! So irrespective of what value is closed, air is still getting into the pump. I checked the pump lid when I relubbed and it looked good (it's brand new, could it be a unseen defect).

So based on the above, it's between the 3 way diverter and pump? Even when I used the hose on those areas, air still accumulated.

Thanks for all the help by the way - this is tremendously helpful, if not an infuriating problem to identify

 

[mas985]

All the valves have o-rings which any one could be the issue.

Did you also check the drain plug gasket at the bottom of the pump basket?

 

[ashg]

All the valves have o-rings which any one could be the issue.

Did you also check the drain plug gasket at the bottom of the pump basket?

Yea I checked them all (both plugs) and relubed. Same with values.

 

[PoolStored]

'Twer it I, I'd rebuild all the diverters:

Amazon.com

and I'd replace the o-rings on the pump lid and drains:

Amazon.com

Amazon.com

If you can get a replacement o-ring for the union on the pump, I'd replace that too.

Inspect the pump basket o-ring sealing surface for irregularities.

I'd use Magic Lube II, or another silicone based lube.

 

[Rancho Cost-a-Lotta]

You have just a few sweep-style elbows. There is one just before the pump. Are you sure that these are pressure rated and not DWV (Drain Waste Vent)? Where did you get the sweep elbows from?

 

[ashg]

You have just a few sweep-style elbows. There is one just before the pump. Are you sure that these are pressure rated and not DWV (Drain Waste Vent)? Where did you get the sweep elbows from?

Good shout but I ordered them from suppy
House. They are all sch40.

Everything is new but I guess I can replace all the orings on the pump. It’s either the 3 way, the pre pump plumbing or the pump itself…..

It was my first rebuilt … it seemed to go so well.

 

[PoolStored]

I guess I can replace all the orings on the pump

For the 12$, I'd replace the o-rings in all the diverters too.
For the couple bucks, if you can replace the o-ring on the union, I'd do that too.

 

[Rancho Cost-a-Lotta]

Good shout but I ordered them from suppy
House. They are all sch40.

Everything is new but I guess I can replace all the orings on the pump. It’s either the 3 way, the pre pump plumbing or the pump itself…..

It was my first rebuilt … it seemed to go so well.

Sounds good. You probably know this, but being Sch 40 doesn't necessarily make them pressure rated. There are a few brands of sweep 90s that are rated for pressure like those manufactured by Waterway products. I did get burned on some fake 411-9130 Waterway 's from Amazon. If they came from a reliable source then you're probably okay. Best of luck!

 

[Newdude]

They all definitely have the deep collars.

For an easy gauge on size from the pics, check the collar on the one after the 3 eay valve to waste. It's almost half as wide as the valve. Lol.

 

[Rocket J Squirrel]

I checked the pump lid when I relubbed and it looked good (it's brand new, could it be a unseen defect).

Yes it could. That happened to me. My clear pump lid looked perfect with absolutely no visible defect. I decided to start replacing parts cheapest first. Replacing the clear lid resolved my air suction leak.