Head

[mas985]

The return side is correct but on the suction side, water can't be pulled, it can only be pushed. Water moves from high pressure to low pressure because the higher pressure pushes on the water. The pump creates lower pressure by removing water from the pump basket via the impeller. This creates a low pressure area in the pump basket which allows the higher atmospheric pressure on the pool to push the water towards the pump.

Pressure gauges can be found in pool stores or online such as ebay, also your filter has a pressure gauge. Ebay also has suction gauges but you can find those at Sears or automotive stores. Flow meters can be had online as well.

However, with just the filter pressure gauge and a little knowledge of your suction side plumbing, you can get a fairly good estimate of flow rates from the spreadsheet I mentioned. The PSI2GPM spreadsheet helps you to estimate flow rates, head loss and energy use.

 

[jordangregory]

Mark,
Thank you so much for all your help with calculations here in the past.
I just went out to my pool today and it is a swamp. I will be spending the next few weeks getting it all cleaned up.
But I was looking around and saw that I really only have 1.5 inch pipes. I had previously told you I had 2 inch pipes.
Does this change the calculations on the amount of head and flow rates?

 

[mas985]

Yes, it does make a difference but at this point your first priority should be cleaning up the algae.

Once the algae is gone and you have backwashed the filter, then post back the filter pressure with configurations that I posted earlier. Also, DO NOT add DE to the filter.

1 -Set valve to skiimer open 100% and wall port open 100%, record the filter pressure.
2 -Set valve to skiimer open 100% and close wall port, record the filter pressure.
3 -Set valve to close skiimer and wall port 100% open, record the filter pressure.

Attached the cleaner and repeat 1 & 2. report back the filter pressures.

 

[jordangregory]

Here is what I came up with:

Skimmer and wall port open 100% = 14 PSI - I don't notice any air bubbles
Skimmer open 100% and wall port closed = 10 PSI - I notice a substantial increase in fine air bubbles
Skimmer closed and wall port open 100% = 12 PSI - I notice some fine air bubbles, but much fewer than when just the skimmer is open
I also added the cleaner to the wall port while the skimmer was closed. This caused the pressure to drop to 8 PSI and I started to see more fine air bubbles coming in.
I also added the cleaner to the skimmer while the wall port was closed. This caused the pressure to drop to 7 PSI and tons of air was coming in.
I also added a cleaner to both the wall port and skimmer while both lines were open 100% and the pressure is at 12 PSI. I notice some fine air bubbles coming in with this.
With a cleaner added to either the wall port or the skimmer with both ports open 100%, the pressure is at 13 PSI and I notice some fine air bubbles coming in.
Whenever I see fine air bubbles coming in, I also see fine air bubbles being pumped back into the pool. This makes it so when under water with goggles, the water always seems cloudy. Perhaps the extra air also makes a better breeding ground for algae

Some other things I have noticed:
The suction on the wall port is very strong. I swam near it last year and as my hand got near it, it was sucked in. My hand was pulled in so hard that is sliced my hand up. I got a very deep cut from that.
Today, I also noticed that when I turn off the pump and then open the strainer basket in front of the pump, it is as if a huge vacuum is behind the basket. All the water rushes out within a second and for about 10 seconds, I hear air continuing to rush in. I am assuming there is a huge

 

[mas985]

That is about what I would expect with 1.5" plumbing. With both suction ports open, you would have about 66 GPM @ 50' of head. The suction is fairly reasonable at 6" hq which is probably why you do not see any bubbles.

However, with the skimmer closed, you would get about 61 GPM @ 54' of head but the suction would clime to almost 15" hg which is very high and explains why you would be drawing in bubbles from somewhere.

With just the skimmer, you could expect about 58 GPM @ 57' but the suction would be at 21" hg which is very high. This seems a little to high for a skimmer. Have you checked that line for any blockage? Also does the skimmer have a float valve or diverter?

With both ports open and the cleaner attached to the wall port, does the skimmer work ok? If so, I would not close either port when using the cleaner. You are just asking for trouble. With 1.5" plumbing, you really need both lines to prevent the suction from getting too high. Also, you should look into an anti-entrapment cover for the wall port to prevent injury.

But the bottom line is that if you are seeing a lot of bubbles, then you have an air leak somewhere. The key is to find where the air is coming into the line.

Today, I also noticed that when I turn off the pump and then open the strainer basket in front of the pump, it is as if a huge vacuum is behind the basket. All the water rushes out within a second and for about 10 seconds, I hear air continuing to rush in. I am assuming there is a huge

That is probably just the filter siphoning water out of the pump basket. Does it start to gurgle?

 

[jordangregory]

To answer your questions:
I don't know what a float valve or diverter is. I just have the little gate thing in front and then a basket sitting inside. It is possible that something is stuck in the skimmer line
Yes, it gurgles quite a bit for about 10 seconds.
My assumption was that the sand filter would be full of water and therefore, would not be able to siphen any water out of the pump basket when the pump is turned off. But obviously, there is a large void in the pump basket.

Also, I went out to check on my pump this morning and found that there was almost no suction in any of my lines. The pressure went from about 14 PSI when I put the pool to bed to 24 PSI when I checked back in this morning. The pump basket had air in it and some water was moving, but it was very, very little. I am assuming that when the pressure goes up in the filter by about 10PSI, it is time to backwash, but the filtering system should still be working. Correct? It seems wrong that the water is almost at a stand still

There are just so many problems! I know everyone keeps telling me to find the leak since bubbles are coming in, but I have done that many times already. I found a leak in the above ground plumbing and then in some other fittings above ground as well. While each fix helped, none got rid of the problem. The only thing left is to dig up the lines. I dug up around the skimmer basket last year and did not notice a leak there.

 

[mas985]

I don't know what a float valve or diverter is. I just have the little gate thing in front and then a basket sitting inside. It is possible that something is stuck in the skimmer line

Given the run to the skimmer is twice as long as the wall inlet, it should have more head loss but it seems to have quite a bit more head loss. At this point I am not certain for sure if there is a blockage or not. Did you say that you tried to back flush the lines or not? It is worth a try.

My assumption was that the sand filter would be full of water and therefore, would not be able to siphen any water out of the pump basket when the pump is turned off. But obviously, there is a large void in the pump basket.

The water in the sand filter is heavy and above pool level so it will try to empty towards the pool. However, unless air enters the system from somewhere, the water will remain in the filter. When you open the pump basket, air can enter at the pump and travel towards the filter which displaces the water inside the filter and allows water to drain from the filter out towards the returns. The filter will drain to the pool's water level and then stop but air will have replaced most of the water that is in the filter. Most systems will behave this way unless there are shut off valves to prevent it so consider it normal.

Also, I went out to check on my pump this morning and found that there was almost no suction in any of my lines. The pressure went from about 14 PSI when I put the pool to bed to 24 PSI when I checked back in this morning. The pump basket had air in it and some water was moving, but it was very, very little. I am assuming that when the pressure goes up in the filter by about 10PSI, it is time to backwash, but the filtering system should still be working. Correct? It seems wrong that the water is almost at a stand still

This is exactly what should happen when you are fighting an algae bloom. The algae plugs up the filter. The filter PSI rises which increases total head loss. The increase in head loss reduces flow rate from the pump.

So you really need to clean up the pool first. Read the pool school articles on how to kill algae but really it just requires using a lot of chlorine until all of the algae is gone. You will need to backwash the filter a lot while you are killing the algae.

Also, keep both suction ports open at all times. Your pipes are not big enough to support one suction line at time. This is what is causing most of the air to enter the plumbing. Once the algae is cleaned up, then you can work on the air leak.

 

[jordangregory]

I now have my pool cleaned up. It is very clear. The Cl is insanely high since I was doing my Cl test wrong and ended up adding 16 gallons of shock in one day, but I assume the Cl level will go down one day soon.
How do you think I should go about finding this leak? I have exhaused what I know to do. I have looked above ground and did all the simple stuff that is always recommended on this website. Do I go to a professional now? And if so, what should I be looking for procedure and price wise?

 

[mas985]

Most air leaks occur in the pump basket lid. Even if you have lubed the gasket correctly, there could be a crack in it which would allow air into the pump so inspect that very carefully. Use a lot of pool lube to make sure you have a good seal. Also, check the pump housing for any cracks.

If you haven't tried to back flush the suction lines, I would try that as well. First try to flush the lines using a drain king on the pump inlet. It should seal well if you get the correct size.

Also, sometimes pressurizing the suction lines can reveal a small leak as water will come out instead of air going in. After you make sure the suction lines are clear, you can then plug them on the pool side with either rubber plugs or threaded plugs. Turn on the hose and see if water comes out anywhere. Unfortunately, it will be tough to see if the leaks are underground but hopefully they are none.

 

[Backyardchemist]

Yes, but they do not make a 1/2 HP Whisperflo two speed. The smallest is the 3/4 HP Whisperflo WFDS-3 or WFDS-24 (uprated) but this is a significantly more powerful pump so you will never be able to run it on high speed for vacuuming or running your cleaner.

Uh-oh. I just replaced an old pump with a WFDS-24 for a similar-sized pump as the OP. Seems to work well on low speed, and vacuuming is WAY better than it used to be on high-speed, but the pump is running pretty hot and drawing max amps at both speeds (it's not low voltage, I checked that). Do you think I've messed up with too much pump? I only have a single 1.5" suction line from the skimmer basket to the pump.

I'm waiting for a pressure/vacuum gauge to arrive in the mail so I can check my TDH under operating conditions.

 

[mas985]

Every plumbing system is different but if the pump is drawing max amps, then the operating point is on the right side of the head curve which means lower head loss not higher head loss.

 

[UPSguy]

jordangregory,

Just so you understand, the 1/2 HP Whisperflo is more powerful than the 1 HP SuperPump you have now so it will likely draw in more air than you are now plus it will use more energy than you do now. The 1 HP SuperPump is one of the smallest in ground pumps on the market although you wouldn't know it by the label.

I thought about sending a PM since this is sort of an old thread but thought I remembered somewhere when I signed up about not doing that since someone else may benifit from the answer. Even though I am looking at AGP pumps I have been searching your posts to learn more and hopefully quit asking questions. Can you please explain your above statement? Is it a full rated vs up rated thing or something in the design of the whisperflow?

Thank you and I hope the OP will forgive me and also hope he got his air leak fixed.

 

[mas985]

The label HP for a pump is a very rough guide as to how powerful it is and how much energy it will use. Because it is difficult to make a motor with less than 1 THP, sometimes manufactures will use a larger motor than the pump actually needs. This is ok and doesn't affect performance or energy use much since both are dictated by the wet end.

In addition, the SuperPump, uses a 1 HP up rated motor with a THP of 1.0 while the Whisperflo uses a 1/2 HP full rated motor with a THP of 0.98 so the motor sizes are about the same. However, if you look at the head curves, the Whisperflo is above the SuperPump so it is a little more powerful pump than the SuperPump.

For the CEC Curve-A, assuming the data is correct:

SuperPump SP2607X102S - 51 GPM, 1194 watts, 2.56 Energy Factor
Whisperflo WFE-2 (high efficiency) - 55 GPM, 1230 watts, 2.69 Energy Factor

So you can see the Whisperflo moves more water on the same plumbing as the SuperPump. Also, it is slightly more efficient doing so but it uses a single speed energy efficient motor while the SuperPump uses a two speed standard efficiency motor.

Labels can be very deceiving.