Hello, I have one 4" Sheer Descent connected to a dedicated Intelliflo VF. I have the pump maxed out at 130GPM but its still not enough to give the sheer descent the full waterfall effect. Can anybody suggest a an alternative pump? We have 2 1/2 piping coming in and 2 1/2 pipe going out to the sheer descent. The pump is about 75 feet from the pool, the sheer descent is about 1 -2 feet above the pool water level. Any suggestions would be greatly appreciated.
Pool Pump Replacement Suggestion for 4-Foot Sheer Descent?
- Thread starter Davidc21a
- Start date
- Jul 21, 2013
- 52,856
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
You really needed 3” pipe for that flow rate. You are probably limited by the suction rate with the 2.5” pipe.
Let’s have @mas985 take a look.
You want to keep the water velocity below 6 ft/sec on the suction and below 8 ft/sec on the pressure side of the pump.
Let’s have @mas985 take a look.
You want to keep the water velocity below 6 ft/sec on the suction and below 8 ft/sec on the pressure side of the pump.
| Pipe Size | 6 ft/sec | 8 ft/sec |
|---|---|---|
| 1.5" | 38 GPM | 51 GPM |
| 2" | 63 GPM | 84 GPM |
| 2.5 | 90 GPM | 119 GPM |
| 3.0" | 138 GPM | 184 GPM |
| 4.0" | 235 GPM | 312 GPM |
That's what I figured, I was told to get a dedicated waterfall pump but I just do not want to replace my pump and get the same results. I'm willing to swap it if I can get more GPM
- Jul 21, 2013
- 52,856
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
- Jan 7, 2012
- 1,461
- Pool Size
- 21000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
- May 3, 2007
- 16,963
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
A 4' sheer descent should required only about 50 GPM to get the full effect. Typical recommendations are 12 GPM/ft.
How do you know the pump is maxed out at 130 GPM? Do you have a flow meter or is it the pump drive that is reporting 130 GPM?
Is there any other return port from the pump to the pool other than the sheer?
Post a picture of the sheer in action and the pump plumbing.
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The suction will begin to have problems at about 17 feet of head loss, which is also the NPSHa at 17 feet of head loss.
For 2.5" PVC pipe, you should design a maximum of about 90 GPM for suction, but you can probably get up to 150 GPM without getting cavitation (For 100' of pipe total equivalent length).
Where are you getting 130 GPM?
Are you sure it is only (1) 4' sheer?
The maximum flow is 20 gpm per foot, which is 80 gpm for 4 feet.
Do you have a filter on the return?
You might need to take suction and return pressure measurements.
www.jandy.com
For 2.5" PVC pipe, you should design a maximum of about 90 GPM for suction, but you can probably get up to 150 GPM without getting cavitation (For 100' of pipe total equivalent length).
Where are you getting 130 GPM?
Are you sure it is only (1) 4' sheer?
The maximum flow is 20 gpm per foot, which is 80 gpm for 4 feet.
Do you have a filter on the return?
You might need to take suction and return pressure measurements.
Sheer Descent Waterfall: Pool Cascade Waterfall | Jandy
Looking for a Sheer Descent Waterfall? Find this Pool Cascade Waterfall for the Perfect Pool Experience. Buy Now w/ a Pool Pro Near You!
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Hi James, I was just going by what the app was telling me not sure if that's what is actually being pushed out. We originally had 4 sheer descents plumbed to this pump. Three were canceled because we ended up remodeling so now the pump is just pushing out the one 4 foot sheer descent. When the pump is being ran at full speed its only pushing the sheer descent about 6" inches out from the wall, I was told it should be pushing it out way more. Here is picture of the pump, its not going through a filter just directly to the sheer descent. After looking at the pump it looks like the suction is reduced to 2" at the pump could this be the issue? Maybe find a pump that accepts the full 2.5"?The suction will begin to have problems at about 17 feet of head loss, which is also the NPSHa at 17 feet of head loss.
For 2.5" PVC pipe, you should design a maximum of about 90 GPM for suction, but you can probably get up to 150 GPM without getting cavitation (For 100' of pipe total equivalent length).
Where are you getting 130 GPM?
Are you sure it is only (1) 4' sheer?
The maximum flow is 20 gpm per foot, which is 80 gpm for 4 feet.
Do you have a filter on the return?
You might need to take suction and return pressure measurements.
View attachment 563547
View attachment 563540
Sheer Descent Waterfall: Pool Cascade Waterfall | Jandy
Looking for a Sheer Descent Waterfall? Find this Pool Cascade Waterfall for the Perfect Pool Experience. Buy Now w/ a Pool Pro Near You!
Attachments
The power is consistent with 130 GPM.
Check the actual power use and the suction and return pressure.
Check the actual power use and the suction and return pressure.
At 80 GPM and 1 foot elevation, you should get a strong flow and about 18" of projection.
At 80 GPM and a 2 foot elevation, you should get a strong flow and about 22" of projection.
Maybe the sheer is clogged due to no filter?
At 80 GPM and a 2 foot elevation, you should get a strong flow and about 22" of projection.
Maybe the sheer is clogged due to no filter?
Maybe the water is going to these returns?
You should get about 18" to 22".
That won't make a lot of difference.
130 GPM is 32.5 GPM/ft.
That should produce about 28" to 34" of projection depending on the elevation.
That should produce about 28" to 34" of projection depending on the elevation.
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6" is consistent with a flow of about 32 gpm, so the available data is very inconsistent.
130 GPM should be shooting out like a firehose.
Maybe show a video of the pump in action and the sheer.