Thanks James.... yeah I dont understand why you wouldn't just follow the engineering plan that was paid for.... makes no sense to me. However, they guy that did this build also put the jets at wrong heights and installed the incorrect light niches and bubbler niche. He had to jackhammer all of the out and cement it all back together. Almost had a heart attack when I saw all the issues. Also had to cut the skimmer off the pool wall and reinstall as they didnt get gunite around most of it.
It's possible to cavitate the pump at higher speeds with 2" pipe.
I would have used 3" pipe.
You might have some sort of restriction in the suction.
You can check the pump display for flow and pressure at different speeds.
You might need to get a vacuum gauge and a flow meter for more detailed diagnostics.
I would have used 3" pipe.
You might have some sort of restriction in the suction.
You can check the pump display for flow and pressure at different speeds.
You might need to get a vacuum gauge and a flow meter for more detailed diagnostics.
Thanks, I have seen it on the Screenlogic app... I have just not paid attention to it. Will check.
Sounds like you are getting cavitation, but it is hard to tell for sure.
See what the pump shows for flow and total system pressure at different speeds.
You might need to put the system in "service mode" to check the readings directly from the pump display as shown in the video.
See what the pump shows for flow and total system pressure at different speeds.
You might need to put the system in "service mode" to check the readings directly from the pump display as shown in the video.
If the plumbing is too small, can the builder still access the plumbing to change it to a larger size?
Yes but it would be painful...some of the run is under dirt along house. Deck is pavers.and about 20ft in.
If you are getting cavitation and you can't change the pipe, then you will have to limit the flow to below the cavitation limit.
Check the system pressure and the filter pressure at different speeds.
The system pressure minus the filter pressure will give you an estimate of the suction head loss.
Anything over 17 feet could potentially cause cavitation because it causes the net positive suction head to be below the minimum for the pump.
Check the system pressure and the filter pressure at different speeds.
The system pressure minus the filter pressure will give you an estimate of the suction head loss.
Anything over 17 feet could potentially cause cavitation because it causes the net positive suction head to be below the minimum for the pump.
The maximum total suction head loss including static and dynamic to avoid cavitation should be limited to 17 to 22.7 feet maximum.
Since your pump inlet will be at least 2 feet above the water surface, the maximum dynamic head loss for the suction should not exceed 15 feet.
Assuming a total equivalent length of pipe at 100 feet, the head loss at 100 gpm for 2" pvc pipe is 15 feet and the velocity is 9.8 feet per second.
So, 100 gpm is probably the best you can do without getting into cavitation.
Ideally, 60 gpm will keep you below the recommended 6 feet per second limit.
www.engineeringtoolbox.com/amp/pvc-pipes-friction-loss-d_802.html
So, 100 gpm is probably the best you can do without getting into cavitation.
Ideally, 60 gpm will keep you below the recommended 6 feet per second limit.
www.engineeringtoolbox.com/amp/pvc-pipes-friction-loss-d_802.html
With 4 jets and 100 gpm, that gives you 25 gpm per jet, which is usually max flow on a jet.
What exact model jets?
You should be able to get up to 100 gpm on the pump.
If you're getting cavitation at 100 gpm or less, then you might have a clog or other issue in the suction line.
As you can see, the pump can get beyond 100 gpm at 2,350 rpm and higher depending on the head loss from everything.
The builder should have use 2.5" as per the design specifications.
I would have used 3" for the spa suction if the flow needs to go above 90 gpm.
Can you post some videos to see if we can hear the cavitation?
