Pump loosing suction

[tenndoc]

Good Morning all -

Just found this forum and it has already helped! We've been battling algae since about mid season, going from a green pool to clear and back again. Reading related threads has been a huge help so, hopefully, bleach, bleach and more bleach will eventually solve the problem.

Since about the middle of the summer we've had the problem with the pump loosing suction. Not completely of course. It will run at around 22 psi and then drop to around 10 and then back up again.

I've filled out the form with our pool info but figure this will make things easier for everyone:

Ours is a 20 x 40 in ground pool ranging from approx. 3.5' to 10' deep. We're using a Century Centurion 1 hp. motor from AO Smith pumping through a Tagelus Sand Filter. We bought our home in March of last year after it had set from neglected for a few years. We drained the pool and pressure washed it and repainted it. We also emptied the filter, replaces a couple of broken pieces inside and refilled with new pool sand. This year the pumping system worked well until about mid summer. When it quite drawing is when we began our battle with algae.

Looks to me as though I'm drawing air from somewhere but I've been unable to locate the source. There is no water around the motor, strainer basket or sand filter.

Thanks in advance -

BTW - this is our first pool -

doc

[tenndoc]

Just want to thank all you folks for coming by and reading about our problem. I can appreciate the head scratching that's going on, been doing a far amount of that myself!

I have suspected the vacuum has drawn a plastic piece from one of our grandchildren's toys into the line causing it to catch and hold stuff clogging up the works. The underground line comes out of the pool for about 25 feet and then makes a 90 deg. turn to head to the pool house. This is something that was probably done 7 + years ago. I am unable to get any kind of plumbing 'router' to make the 90 deg. turn so I'll probably dig up the area at the elbow and replace it with two 45 deg. fittings. At least then I'll be able to 'rod' out the line if needed.

As before, this is our first experience with a pool of any size. When we opened the pool this spring (we were late so the pool guys really got in my wallet to get everything clean) I found more than one FROG in the strainer in the pool house at the pump! ! ! Obviously it was really drawing water then!

So, thanks again for pondering our situation and thanks for a great forum. Dust wouldn't billow from my wallet every time I open it if I'd known all this beforehand. And to think, the guy at the pool place was offering to come by and 'service' our pool each week for only $150 a month! I do have to admit though - it was his mention of borates that got me to looking and led me to the pool forum. :-)

doc

[mas985]

You could try back flushing the suction line and see if something comes out. First remove the skimmer basket and pump basket lid, then use a hose wrapped in a wet towel and place it in the suction line entering the pump and try to seal it in the pipe. Turn on the water and see if anything comes out of the skimmer.

[tenndoc]

Thanks mas985. I tried that using an expandable bladder. After pushing water from both ends of the line I was able to force some debris out of the line. Thats one of the major reasons I concluded that there must be something in there catching and holding stuff.

Thanks for doing a little head scratching for me on this. Any other thoughts please let me know.

BTW, you can get expandable bladders that screw on the end of a garden hose in different sizes. Works fairly well on some clogs around the house and is chem free! I got mine at Lowe's but most any hardware store will probably have them.

Thanks again

[mas985]

I have done it both ways but I find that a straight hose can get more force into the pipe so you might want to try it that way too.

[tenndoc]

That was the first way we tried and honestly there just wasn't enough 'push' to move things along. Thats what led to using the expandable bladder. It will hold water, thereby increasing pressure, until the bladder expands to fill the inside diameter of the pipe. Once reached, the water is forced out the bladder. It's a dedicated vacuum line that was added sometime after the original construction.

Thanks again for your input and for taking time to help us figure it out

doc