Noisy New Pump

[fyton2v]

I'm a new pool owner... again... and going through initial start-up. I have 3 pumps on my pool.

1. Filter pump.
2. Spa booster pump for jets
3. Water feature booster.

The filter and spa pumps are working quite well. My 1.5HP water feature pump is pretty noisy and it runs louder than the 3HP spa booster. All the pumps are Jandy Stealth models with the filter pump being the ePump. Anyway, I think I know what the problem is, but I'm looking for confirmation. See below:

The water feature pump sucks water through a separate drain in the pool and supplies water to 3 things: Two separate sheer decent waterfalls and 1 return inlet in the spa to add more water to spa's cascading waterfall. This pump is loud and doesn't run smoothly. There is no cavitation, but I can see several tiny air bubbles through the window. I think my problem is that the plaster company put a anti-vortex drain cover over the 2" return in the spa. Would that cause back pressure and make the pump struggle?

Oh.. another interesting phenomenon on the water feature plumbing. After you turn the water feature pump OFF the sheer descent waterfalls continue to run through some awesome siphon action. No electricity and perpetual waterfall. While this is kinda cool, it is a little inconvenient to stop. I have to go manually turn the valves on their return lines to shut each one off individually. What's the solution here? A auto valve actuator?

Thanks everyone. It's been quite an adventure so far...

 

[Lershac]

That's not siphon action... You gotta have some pressure there from something. Pic of your layout?

 

[fyton2v]

Was thinking about this on my way to work. I think it is siphoning, but not from the pool. I think it's from my spa via the return I mentioned above. It's a raised spa and the water level is above the sheer waterfalls. The plumbing for this stuff rises above the spa's water, but after the pump kicks off I think it's still siphoning over the loop. I haven't let it run long enough to see if my spa drains. Will test this evening.

Thanks!

 

[PoolGuyNJ]

If the spa's water level is higher than the sheer descents', and there is no check valve on the line from the water feature pump to the spa, it could siphon until either the two are nearly equal or air gets in the spa's line, which ever occurs first.

If there is a check valve but it's just after the pump discharge, what you see happening is no surprise.

If there were no check valve, the spa would drain into the pool until air entered and the sheers would likely have stopped immediately and the lines to sheers would also drain into the either the pool or spa..

Scott

 

[Lershac]

ah, I had a mental picture of a sheer waterfall being something high... yeah, a check valve would help that or an actuator to turn it off. As long as the sheer waterfall is lower than the level in the spa you would get a backflow from the spa into the sheer waterfall until the water fell either to the spa inlet level or the sheer waterfall level.

 

[mas985]

I think my problem is that the plaster company put a anti-vortex drain cover over the 2" return in the spa. Would that cause back pressure and make the pump struggle?

Depends on the covers used but most are fairly low head loss.

However, the noise you are hearing from the waterfall pump could be just high flow rate water noise. Pumps that operate with low head loss and high flow rate tend to be quite noisy. How large is the pump and what size/length are the pipes from the pump to the waterfalls?

 

[fyton2v]

My Internet is down so posting this from my phone. Please excuse spelling errors.

I was able to do more thorough testing of all pumps yesterday in the daylight. Issue with waterfall solved. You are all correct that I need a check valve between my spa and the 2 sheer waterfalls. The noise issue is more confusing though.

I have 3 Jandy pumps:

1: 3hp single speed spa jet pump. Only plumbed between spa drains and spa jets. This pump works great. Smooth and quiet.

2: 1.5hp single speed waterfall booster. Simple plumbing. It pulls from a drain in pool and has 3 separate returns. 1 in spa to boost spa waterfall. And 2 for the sheer waterfalls. I think it's 2.5" pipe on the suction side and 2" on the return. Pretty sure. This one is loud. I think the noise is coming from air as it passes through the pump. There are always tiny bubbles in the basket. I've the cover and the union fitting and all looks air tight. It's tough to tell if it's pulling in air for the unions, but nothing is leaking.

3: filter pump. This is a 2hp VS ePump. It's quiet up to about 3000 rpms, but this pump has more turbulence in the basket especially with suction side pool sweep on. Above 3000 it gets louder. Similar noise to waterfall booster.

None are screaming loud. I'm just a bit confused why the spa jet pump is perfect while the others have air and can be louder than the biggest HP pump. I can post some pics once Internet is restored.

Thanks all.

 

[fyton2v]

Oh. I took off the drain cover that was blocking the return in the spa. It didn't really make a difference.

 

[fyton2v]

adding some pics to make this thread more interesting .

Mas,

Would air bubbles or turbulence be caused from too low of a TDH for type of pump being used? If I understand correctly, these stealth pumps are "high head" and I'm wondering if head loss is too low on the return side of my filter and waterfall booster pumps. I could have this concept totally backwards.

On the booster side it's a short return back to the pool (maybe less than 25' on average) via 3 seperate 2" pipes. The suction side is 2.5".

On the filter side the returns are 2" pipe scaled down to 1.5" pipe to 6 wall fittings (4 in pool, 2 in spa). The wall fittings have 3/4" eyeballs. Suction side is 2.5" from drains (skimmer is inline with the drains) and is scaled down to 2" at the equipment pad. So... 2" into pump suction and 2" out through big Jandy CV filter, heater, then returns back to pool and spa.

Some pics... and this equipment pad is about 20' away from the pool water.

Pipes from left to right against the wall:
1. Spa return
2. Pool return
3. spa drain
4. suction into filter pump
5. suction for pool sweep
6. suction for skimmer and drain #1
7. suction for skimmer and drain #2
8. water fall #1
9. water fall #2
10. spa return from booster
11. suction from spa drains
12. return for spa jets
13. air intake for spa jets

[attachment=1:2jiysm06]photo2.JPG[/attachment:2jiysm06]

[attachment=0:2jiysm06]photo1.JPG[/attachment:2jiysm06]

 

[mas985]

Would air bubbles or turbulence be caused from too low of a TDH for type of pump being used? If I understand correctly, these stealth pumps are "high head" and I'm wondering if head loss is too low on the return side of my filter and waterfall booster pumps. I could have this concept totally backwards.

Yes, if the return head loss is too low, it can cause not only noise due to the high flow rate but also cavitation on the suction side of the pump. This is a condition called run out or in other words, the pump has run out of NPSH (net positive suction head). On the head curve, this is the right most point where the curve stops.

The pump may also be sucking in some air which adds to the problem but I suspect it is mainly the water flow that you hearing in the pump chamber and perhaps cavitation. One way to tell is to close the return valves about 1/2 each and see if the noise subsides.

You have three return pipes but only one suction pipe which is shared with the circulation pump. This means the pump is seeing much lower return head loss than suction head loss which is a really bad situation and can easily cause cavitation.

[EDIT] - I did a few calculations based upon a single 20' 2.5" suction run and three 20' 2.0" returns and the pump pretty much has to be in run out condition so it is probably cavitation that you are hearing. Water noise can be loud but cavitation sounds like you are pumping gravel.

 

[fyton2v]

focusing on the booster pump for the moment:

"pumping gavel" is a very good description of the sound. I went out to reduce/close the returns from that pump and I think the sound goes away, but it's a little hard to tell. Restricting flow through the valves creates a different noisy situation. As the pump smooths out the rush of water through the partially closed valves is the loudest thing happening on that pad.

The plaster company is going to come out and put a return fitting in the spa. At the moment I just have an open 2" pipe headed there. I'm thinking that I'll reduce that down with a 3/4" eyeball. That should increase the head a bit. It's worth mentioning that even with the valves restricted I'm still seeing tiny bubbles... in my pump... makes me unhappy (there's a song in there somewhere). I need to figure that one out.

In addition to adding the eyeball, would it help if I were to eliminate the 2.5" pipe on the supply side of the pump? Without a whole lot of trouble I could make it 2". So it would be a single 2" pipe feeding 3 separate 2" runs vs. the single 2.5" pipe feeding the 3 runs.

Need to figure out a way to repay all the great people on this forum. I never would've made to this point with the help.

 

[mas985]

In addition to adding the eyeball, would it help if I were to eliminate the 2.5" pipe on the supply side of the pump? Without a whole lot of trouble I could make it 2". So it would be a single 2" pipe feeding 3 separate 2" runs vs. the single 2.5" pipe feeding the 3 runs.

No, that would make things worse. The problem is that you have less head loss on the returns than the suction. Most pumps will work better and quieter if the return to suction head loss is at least 2:1. Even if you had a 4" pipe to reduce the suction head loss, it would still not solve the problem because the pump would still be in a run out condition. Basically, the pump is producing too much flow rate and does not have enough return head loss.

But when you have both waterfalls off and only the spa running, is the pump any quieter? In that mode, the head loss would be a little better than 1:1 return:suction but not much and it would still be very close to the end of the head curve. If you added a single 3/4" eyeball, that should be enough to restrict the flow and push the operating point onto the head curve. However, you would still have the issue when running the waterfalls and I assume you like the way those look in terms of flow rate.

BTW, do you have uprated 1.5 HP or the full rated version (SHPM vs SHPF)?

 

[JamesW]

Is there any way you could post a video at Youtube showing the pump so that we can hear it and see inside the basket?

It would help if you could put a vacuum gauge on the suction side and a pressure gauge on the return side. Since this is a brand new pool, I would think that the builder would be willing to help with this.

It would be easy to drill and tap a 1/4-inch pipe thread into the PVC. You can buy the 1/4-inch pipe thread tap at most hardware stores. The tap will specify the drill size. If I remember correctly, the drill size is 7/16-inch. Be careful when drilling, as the drill goes through the PVC it can hit the other side of the pipe if you're not careful to control the penetration.

A flowmeter would also help, but unfiltered water will clog some types of flowmeter.

Here is a video about drilling and tapping PVC. The guy rambles for a while, but eventually gets it done. He puts the tap all of the way through, which is not right, and wouldn't work anyway. Just put the tap in about 3/4 of the way in.
http://www.youtube.com/watch?v=ayduerGoCyw

It's also possible that the suction is obstructed. Sometimes plaster or other debris will get in the main drain and create a blockage. Another possibility is rocks or concrete chips in the impeller. For new construction, this is not too unusual.

Vacuum and return pressure will give us a good idea of where the pump is on the head curve.

 

[fyton2v]

Ok... couple things that I need to correct. I said the 3 returns were 2", but I they are actually 1.5". I went back to some photos to verify. The pump is full-rated 1.5HP (SHPF). It does get a bit quieter when I turn off the other 2 water falls, but it's still kinda loud. So this would be 2.5" in and a single 1.5" return with a vortex of bubbles inside the basket. I'm starting to wonder if it's a situation at that 3 pipe junction that's causing the bubbles.

What I now that was another cavitation issue with my filter pump doesn't seem to be the case. The gravely noise is actually coming from a Jandy 3-way valve on the intake side. it's the one that diverts suction from the pool to the spa. Cavitation in a valve? Need to do more research. This start-up process is soaking up an unbelievable amount of time.

In addition to adding the eyeball, would it help if I were to eliminate the 2.5" pipe on the supply side of the pump? Without a whole lot of trouble I could make it 2". So it would be a single 2" pipe feeding 3 separate 2" runs vs. the single 2.5" pipe feeding the 3 runs.

No, that would make things worse. The problem is that you have less head loss on the returns than the suction. Most pumps will work better and quieter if the return to suction head loss is at least 2:1. Even if you had a 4" pipe to reduce the suction head loss, it would still not solve the problem because the pump would still be in a run out condition. Basically, the pump is producing too much flow rate and does not have enough return head loss.

But when you have both waterfalls off and only the spa running, is the pump any quieter? In that mode, the head loss would be a little better than 1:1 return:suction but not much and it would still be very close to the end of the head curve. If you added a single 3/4" eyeball, that should be enough to restrict the flow and push the operating point onto the head curve. However, you would still have the issue when running the waterfalls and I assume you like the way those look in terms of flow rate.

BTW, do you have uprated 1.5 HP or the full rated version (SHPM vs SHPF)?

 

[fyton2v]

I will do these things, but the gauge install will take some time. Youtube would be easy. I'll show all 3 pumps for a side by side comparison.

Is there any way you could post a video at Youtube showing the pump so that we can hear it and see inside the basket?

It would help if you could put a vacuum gauge on the suction side and a pressure gauge on the return side. Since this is a brand new pool, I would think that the builder would be willing to help with this.

It would be easy to drill and tap a 1/4-inch pipe thread into the PVC. You can buy the 1/4-inch pipe thread tap at most hardware stores. The tap will specify the drill size. If I remember correctly, the drill size is 7/16-inch. Be careful when drilling, as the drill goes through the PVC it can hit the other side of the pipe if you're not careful to control the penetration.

A flowmeter would also help, but unfiltered water will clog some types of flowmeter.

Here is a video about drilling and tapping PVC. The guy rambles for a while, but eventually gets it done. He puts the tap all of the way through, which is not right, and wouldn't work anyway. Just put the tap in about 3/4 of the way in.
http://www.youtube.com/watch?v=ayduerGoCyw

It's also possible that the suction is obstructed. Sometimes plaster or other debris will get in the main drain and create a blockage. Another possibility is rocks or concrete chips in the impeller. For new construction, this is not too unusual.

Vacuum and return pressure will give us a good idea of where the pump is on the head curve.

 

[fyton2v]

Videos! First time I've ever uploaded to Youtube.

1. The filter pump on full (3450 rpm). It's kinda loud, but if i cut back the RPMs it gets very quiet under 3000. On full blast it works OK with all suction valves open full. However, I need to increase suction to my pool sweep by closing these valves a bit and then the pump struggles. More noise, more cavitation. I don't think it's able to pull enough water from the pool to keep up with the returns. In this configuration most of the gravely sound is coming from the 3 way valve. When the valves close you can hear the gravely sound shift to the pump somewhat. Figuring out the right settings for the pool sweep operating efficiently should be really fun (that is sarcasm).
http://www.youtube.com/watch?v=Phit5gqa7rc

2. My spa jet pump. This one is single speed and seems like it's running perfectly.
http://www.youtube.com/watch?v=EpOSpUgq0rs

3. The waterfall booster pump... and problem child. You can see that when I close the valves it quiets down. It still is loud, but a lot of the sound is coming from water rushing through the valves. Even when the valves are restricted it's still bubble city.
http://www.youtube.com/watch?v=Ldy_0sj3KNU

Enjoy!

 

[mas985]

I wouldn't mess with the plumbing to measure pressure and suction. You can get perfectly valid measurements from the pump drain plugs without any plumbing modifications.

Even with 1 1/2" plumbing and all three pipes open, you might still be exceeding the capabilities of the pump. However, if only one pipe was open, then the operating point should be well within proper operating points so there could be some other issues going on.

A pressure and suction measurement from the pump might help to narrow down the issue but I would highly recommend doing that from the drain plugs rather than cutting into your plumbing.

 

[JamesW]

The filter pump sounds OK and the basket looks good and solid. 2-inch PVC is really too small for the ePump, especially if it's the 2 H.P model. The JEP 2.0 is actually a 2.7 H.P pump. The JEP 1.5 is actually a 2.2 H.P pump.

On full run out, the 1.5 and the 2 H.P will hit 150 gpm. 2-inch PVC should really not exceed about 60 gpm (ideal) to 80 (not ideal). The sound is due to excessive flow rate. If, for some reason, the suction valve does not fully open, then the issue will get worse. Even 3000 rpm is too high for 2-inch PVC; you should keep the speed to below 3000 rpm.

http://www.zodiacpoolsystems.com/Produc ... A6219.ashx

The spa jet pump sounds good; I'm guessing the return pressure is sufficient to keep the pump in the proper part of the pump curve. A pressure gauge would confirm, but is probably not necessary as it is running well.

The waterfall booster pump SHPF 1.5 does sound like it is running with too little return head pressure. At full run-out it will do 160 gpm. It is a high head pump, which is not the right choice for a waterfall. The correct pump would be the Waterfall pump, which is a High-flow, low head pump. As the name implies, it is made specifically for waterfalls. Depending on the design flow rate, the 2-inch PVC suction is probably too small. What is the design flow rate for the waterfalls?

http://www.zodiacpoolsystems.com/Produc ... L6204.ashx

http://www.zodiacpoolsystems.com/Produc ... rFall.aspx

http://www.zodiacpoolsystems.com/Produc ... A6223.ashx

Note: After seeing the videos, I don't think that pressure gauges are necessary.

 

[fyton2v]

aha! I just found out that the 2 regular spa returns have drain covers over them. This will help explain (at least partially) the cavitation in the filter pump. Essentially there are two 1.5" pipes throwing water into my spa without restriction. These will end up getting 3/4" eyeballs too. Hopefully tomorrow.

I don't know how you pool pros put up with this stuff.

 

[fyton2v]

On the filter pump piping. It's sucking from 3 separate lines... 1 sweep line and 2 seperate 2.5" drain/skimmer lines. If I were to replace the suction side of the pump with 2.5" mate with the 3 suction runs (where it's 2" now) would this help? If not, what if I do that, plus put 2.5" pipe past the 3-way jandy valve (you can see this stuff in the pictures above) to mate with the 2 separate return runs to the pool and spa? Fixing my inlets in the spa will help too.

I really want this to run correctly. Otherwise it'll drive me crazy. I'm my own plumber. I'd rather do the work myself than bring back the plumber who installed this in the first place.

sigh. Thank you!

The filter pump sounds OK and the basket looks good and solid. 2-inch PVC is really too small for the ePump, especially if it's the 2 H.P model. The JEP 2.0 is actually a 2.7 H.P pump. The JEP 1.5 is actually a 2.2 H.P pump.

On full run out, the 1.5 and the 2 H.P will hit 150 gpm. 2-inch PVC should really not exceed about 60 gpm (ideal) to 80 (not ideal). The sound is due to excessive flow rate. If, for some reason, the suction valve does not fully open, then the issue will get worse. Even 3000 rpm is too high for 2-inch PVC; you should keep the speed to below 3000 rpm.

http://www.zodiacpoolsystems.com/Produc ... A6219.ashx

The spa jet pump sounds good; I'm guessing the return pressure is sufficient to keep the pump in the proper part of the pump curve. A pressure gauge would confirm, but is probably not necessary as it is running well.

The waterfall booster pump SHPF 1.5 does sound like it is running with too little return head pressure. At full run-out it will do 160 gpm. It is a high head pump, which is not the right choice for a waterfall. The correct pump would be the Waterfall pump, which is a High-flow, low head pump. As the name implies, it is made specifically for waterfalls. Depending on the design flow rate, the 2-inch PVC suction is probably too small. What is the design flow rate for the waterfalls?

http://www.zodiacpoolsystems.com/Produc ... L6204.ashx

http://www.zodiacpoolsystems.com/Produc ... rFall.aspx

http://www.zodiacpoolsystems.com/Produc ... A6223.ashx

Note: After seeing the videos, I don't think that pressure gauges are necessary.