This is really only the second full year I’ve had the pool (went in at end of season in 2020) so pump is newish. It is a Hayward Superpump 700 single speed. A few times since I’ve opened the pool this year, in the mornings or after I vacuum, and start the pump up, it seems to get going fine, then after about 5 minutes all of a sudden the water level in the skimmer drops and the water pours into the skimmer opening quite forcefully for a minute, then it seems to stabilize and go back to normal for a few minutes, and then repeats this indefinitely unless I switch off the pump and restart. After restarting sometimes it will be fine. When it does this the water inside the pump is full to the top but it looks turbulent, and it’s not usually. Any ideas on what might be going on here? I’m at a loss. Thanks.
What’s the cause of my pump system acting up like this?
- Thread starter Toad_stools
- Start date
- May 3, 2014
- 59,017
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Toad,
The only thing that will cause that problem is a stuck weir door, just like Marty says...
Thanks,
Jim R.
The only thing that will cause that problem is a stuck weir door, just like Marty says...
Thanks,
Jim R.
Thanks is for the replies guys. I don’t know I checked the weir this AM and it seems to be ok. Turned the pump on this morning and same thing happening. It’s like a cycle of about once every minute. The water in the pump drops right down, jets sputter a bit, and water in the skimmer drops suddenly and pours in, then everything stabilizes for a minute and water levels come back in pump and skimmer. Pressure gauge also fluctuating up and down while this occurs. The weir is not stuck. It’s like the whole system can’t seem to equalize with water. I don’t seem to have any leaks.
I attached a couple pics here to show the skimmer. When the water drops it seems to be pulling in air and the jets are just sputtering like crazy. 
TS,
Either the water in your pool is way too low or the weir door is sticking up. It is just about impossible for the pump to pull all the water out of a skimmer quicker than the water can "fall" in from the pool.
As a test, pull your weir door down and then turn on the pump and see what happens. You won't get much skimming action with the weir down, but the skimmer basket should not empty.
Thanks,
Jim R.
Either the water in your pool is way too low or the weir door is sticking up. It is just about impossible for the pump to pull all the water out of a skimmer quicker than the water can "fall" in from the pool.
As a test, pull your weir door down and then turn on the pump and see what happens. You won't get much skimming action with the weir down, but the skimmer basket should not empty.
Thanks,
Jim R.
Thanks Jim. If I hold the weir down it still does it. I don’t know maybe not enough water in the pool but the level is at the recommended level (I think) and I’m positive this is the level it was at most of last year. I put the hose in and am adding another couple inches of water and will see if that helps. Attached a pic of current water level. Do you think it’s too low?
TS,
The water should be about in the middle of your skimmer opening. I can't tell where the bottom of the skimmer is located in the pic, but it does not appear to be too low to me.
I like the idea of adding water and see what happens.
What is in the bottom your skimmer basket?
Anything that might impede the water flowing out of the basket might cause the problem you are having.
Thanks,
Jim R.
The water should be about in the middle of your skimmer opening. I can't tell where the bottom of the skimmer is located in the pic, but it does not appear to be too low to me.
I like the idea of adding water and see what happens.
What is in the bottom your skimmer basket?
Anything that might impede the water flowing out of the basket might cause the problem you are having.
Thanks,
Jim R.
Maybe these pics will help a bit to diagnose. Not great but best I can without getting in and the water is 70 degrees so I’d rather not. Should the level be up over the weir? 
I had a sock full of CYA pellets in there but it does it with or without the sock. And I’ve had the sock in there since opening last week but I took it out today to test if that was the culprit. But seems not.
- May 3, 2014
- 59,017
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
That level of water is fine for my VS pump at lower rpm, but I suspect your SS pump is pulling alot more water. Raising the water level should help.
Thanks. This pump does seem to have a lot of umph. I notice when I vacuum the pool it pulls dirt from many feet away. I do t know maybe that’s normal for pumps but it does seem to pull a lot of water. Hopefully raising the level will do the trick. Will report back.
TS,
I'd bring it up to the screw in the side of the skimmer mouth.
Thanks,
Jim R.
I'd bring it up to the screw in the side of the skimmer mouth.
Thanks,
Jim R.
Low water was the issue guys. Put an inch in and everything is good. Relieved. Thanks a bunch.