Air in pump basket because of drain built wrong?

[Chomdo]

Hi guys,

I have a quick question about a problem with my skimmer. So I've been having air in the pump basket since some pipes were changed last month and I've been trying to figure it out for a week now. I've done everything possible and the normal troubleshooting for this problem. Nothing helps and now I have one final observation/question that I would need an answer to.

So for some reason the previous "pool guy" changed the draining line to go up about about 40-50 cm from the ground and then connect to the skimmer pipe straight from above (as you can see in the picture). I didn't think of it much that time, but just noticed from older pictures that it used to run along the ground level at the same height as the skimmer pipe and the pump. Somehow with common sense just seems weird that the draining pipe would run 40-50 cm higher than the skimmer line and pump and then connect to the same line. Could this be causing the problems with the skimmer and the air in the pump basket?

 

[peirek]

Hello Chomdo and welcome to Trouble Free Pool

I am assuming the drain pipe is your main drain connection? Would not expect the elevation or length cause air to be drawn in.

Sounds like you have a suction side leak. Try following this: Pool School - Suction Side Air Leaks and focus on the new piping joints.

 

[Chomdo]

Yes it is the main drain line, which connects to the skimmer line before entering the pump. I was thinking it could cause the air lock like in the picture above, no? My main drain pipe connects to the skimmer line and pump just like in that picture.

I've been trying to solve this problem for weeks and I've gone trough all the basic and more advanced procedures. There seems to be nothing else wrong with the system and no air leaks. When the pipes (skimmer and main drain lines) were changed last month, the other return was blocked due to a leaking pipe, so now I'm running on only one return. Could that also cause problems or air in the pump basket?

 

[peirek]

Continual air in the pump basket is coming from a continual air leak. The air lock described above, as I understand it, would block or partially block water from getting through. I don't see how this would cause a steady flow of air into the pump basket.

Have you gone through the suction side air leak troubleshooting steps? Maybe shut off the main drain and skimmer alternately to eliminate one or the other?

 

[Chomdo]

No leaks found anywhere. I have done the suction side troubleshooting steps countless times and checked many other things too, but the only thing I can figure out is that the main drain line and skimmer line are now positioned weirdly (by the guy who came to fix the leaking return and had to change a few pipes). I did have a leaking pvc connection in the skimmer pipe and that was fixed, but it really didn't change anything. Or maybe there's a bit less air in the pump basket now, but it still doesn't prime 100 %.

I've also tried using the skimmer and main drain alternately like you suggested but about the same amount of air remained in the pump basket. Only when I turn the filter to backwash or drain mode, I can get the pump basket 100 % full quickly. Then when I open the valves and set filter at filtration more again I can run the pump at maybe 95 % full of water. Just that that air bubble was not there before the pipes were changed so something must have happened.

I can post a picture of the air in the basket. I guess it's not too bad, but I would like to know can it cause any harm to the system having a bit of air like that in the pump basket?

 

[Chomdo]

Something quite interesting just happened and it may have solved the whole problem. I noticed there was a big chunk of concrete stuck in the return inlet. I screwed off the eyeball and flushed out the chunk. After that my pump started to prime perfectly.
Now I'm not sure did the pump start to prime because all the stones blocking the return pipe came out or because I removed the inlet eyeball to allow the water to be pumped into the pool trough a much larger hole?

I guess there's no point for me to put the eyeball back because I only have one return and I felt like the water pressure was too high to come out of that tiny hole anyway?

The filter's pressure gauge was shoving constantly 75 before I removed the eyeball and the stone. Now it's running at about 25.