Silent pump for small onground pool with solar and heat pump

[pmcd]

I have a Hayward Power-Flo Matrix two speed pump with a 100sqft Harward cartridge filter. It is plugged into a three pronged outlet via an 8 ft cord or so.

- 160 sqft of Aquatherm solar panels 30 ft away and up 12' on a flat roof
- Sta-rite salt system
- roughly 7000 gallon pool half in the ground and constant 4' depth
- 50k btu heat pump

At high speed all works but the pump is quite noisy and it uses maybe a 1/3 of the heat pump's power draw. All components work ( solar heat pump and so on). Heat pump only comes on if water from solar is below 80.

At low speed the flow is not enough to run the solar, salt system and heat pump but the noise level is great. It is enough to run the heat pump and salt system but not the solar.

I want a pump with an on/off switch and a three pronged stand cord for 115v. Is there a pump that is quiet that would work? Perhaps a 3/4 HP or even 1/2HP? It has to work with the Hayward Xstream filter.

I have basically shut down the solar and run the pump at half speed along with the heat pump. Much better and am thinking my solar adventure was a mistake ( my previous Enersol panels, Zodiac salt system , Sam heat pump seemed to be able to handle the pump being at 1/2 speed but the Enersol panels developed the black dust problem and a nightmare ensued).

Was thinking a Pentair Dynamo 3/4 HP pump might be a nice compromise which has the advantage of self-priming ( I am on the border of needed that) and would hopefully be quiet). Might not work with the filter? Might not fit on the base where the Power-Flo matrix is? Horizontal discharge issue?

Am at a loss and any advice would be appreciated. Energy savings a bonus but silence is the main priority. The Hayward Power Flo has always been loud at full speed and silent at half speed.

The expensive route would be variable speed but that would involve expensive electrical work, expensive pump, no on/off switch and too many delicate components that might fail.

 

[CJadamec]

My VSP pump is virtually silent up to about 2200 rpm and about that rpm I wouldn't exactly call it noisy but you can hear it. There have been plenty of time I have to check the basket or feel the return to make sure its on. It might be an expensive solution to your problem though. The super flo pump I have will run off a standard 110v pump outlet.

 

[Hayward Pool]

Just a thought on the noisy pump on high speed. If it is quiet on low speed I am going to assume there is not problem with the bearings. This is a hydraulic noise I think
.
Normally a pump will get noisy if it is trying to pump more water than the suction is receiving.

 

[mas985]

Given the rise for solar, the pump you have is about as small as you can go. The 3/4 HP would not be that much quieter.

However, if you do have an issue with the pump, it could possible be fixed. A video would sure help to assess.

 

[pmcd]

Thank you for all the information.

- the Hayward 1 HP pump is noisy, but I suspect that it is just a bit noisier than my old Pentair 1 HP Dynamo. At half speed the Hayward is virtually silent and so I got used to the bliss! Too bad a 3/4 HP pump would not be significantly quieter.
- I suspect the new solar panels added just enough head to bring the flow below the minimum required for the heat pump. Had to add more turns since the Enersol product was essentially a bunch of vertical sheets. The new set up required two panels joined in series because of the roof geometry.
- apart from a 12' rise and 30' piping run, which adds at most 18' of head the turns in piping would not take you past 30 feet of head which seems to be within the capabilities of low powered pumps. I am not after efficient solar but just solar that compliments the heat pump. These head calculations are really complicated! Is there some rule of thumb for estimating the amount of head in a setup?

Anyway, will look into the Pentair Super Flo VS. I suppose that might require either another adaptor or a new cartridge filter? Also, it doesn't seem to just plug in to a three pronged GFCI outlet or is this something that you have to hardwire?

 

[mas985]

What is the filter pressure with and without solar engaged?

I have a couple of tools in spreadsheets that I use to calculate head loss (see signature). But you can get a rough estimate from just the filter pressure.

 

[CJadamec]

You shouldn't have to change the filter if you change the pump.The superflo vs is hard wired but will run on either 110 or 220v. You could wire a plug onto the pump for your 3 prong pump outlet. Just make sure to use 12 gauge wire.

 

[pmcd]

What is the filter pressure with and without solar engaged?

I have a couple of tools in spreadsheets that I use to calculate head loss (see signature). But you can get a rough estimate from just the filter pressure.

For some odd reason the filter pressure does not change when I engage the solar, at full speed. It is 12psi. At half speed the filter pressure is 6 psi ( without solar). If I start the pump at full and the solar is on I can switch the pump to 1/2 speed and solar, heat pump work fine. Salt complains about flow though. This is impractical as I have the solar on an automatic system. At low speed I must be right on the border for having the solar and heat pump working. My Aqua Rite salt system is very picky with flow and won't ever work with solar and half speed. My previous salt system from Zodiac did not complain.

I must admit to being less than enthusiastic about the solar given the need to run the pump at full noisy speed. The Super Flo VS would be quiet as long as I could get away with 2200 rpm or so. At 3000 rpm it is apparently louder than the Power Matrix at full speed according to our local dealer ( the claim is that variable speed pumps are louder at higher rpm's). In addition, it is expensive and might require expensive electrical work. Nice pump though.

Odd that filter pressure doesn't change when switching to the solar panels. I didn't test that at low speed.

 

[mas985]

For some odd reason the filter pressure does not change when I engage the solar, at full speed.

It should.

Does the filter gauge go to zero when the pump is shut off? You might try tapping the gauge to see if it changes. When they get old, sometimes they stick.

Also, are you bypassing any water around solar? There definitely should be a pressure rise with solar. Otherwise, it may not be going through the panels.

 

[pmcd]

It should.

Does the filter gauge go to zero when the pump is shut off? You might try tapping the gauge to see if it changes. When they get old, sometimes they stick.

Also, are you bypassing any water around solar? There definitely should be a pressure rise with solar. Otherwise, it may not be going through the panels.

It is definitely going through the panels. When the panels are engaged the path is pretty obvious and I can tell by the water temperature that the water is going through the panels. The gauge does go to zero when the pump is off. I will check again tomorrow. Might have misread. It could have gone from 12psi to 14psi with the solar working but I was looking for a drop, not an increase which is why I think it did have the 2psi increase. The panels are only one story up but obviously a two speed pump must really be taking a hit at half speed. As I mentioned, once the solar is flowing I can switch it to low and it works fine. It just won't work properly to "prime" the panels from low. There is also the worry that the salt generator requires a certain flow.

From what I gather, noise levels don't change a lot by going .75, 1, 1.5 HP ( I went and listened to some). It's lowering the rpm's that really seems to affect the noise level.

 

[mas985]

Normally, when you switch from high to low speed, the pressure should drop by about 75%. Because it is at 6 PSI, it makes me think you are losing prime when switching to low speed. 12' high panels will drop pressure by over 5 PSI. Do you have a VRV and is it on the roof? If so, that could be the problem. The solution is to drop the VRV to about 6' above the pump on the panel supply side. However, you may still need to prime the panels on high speed because it is unlikely you can prime on low speed. Unfortunately, I don't think that controller supports a high speed prime with an automatic drop down to low speed but others do.

Another solution would be to remove the VRV all together and have the panels always primed. Of course you would need to drain them manually before winter.

 

[pmcd]

@mas985

I do have a VRV. It is halfway up the roof so around 6' above the pump and close to the panels which are around 25' or so away. I have to drain the panels in any case for the winter for fear of freezing. Since they are on a flat roof and not the rubber Enersol which seemed to cause the blast dust issue with my pool this is yet another hassle with them.

I could try with a pump with slightly higher flow such as the Pentair Opti Flo/ Dynamo or perhaps the VS. Really, I am after the silence of the half speed pump. I am beginning to have real doubts about the use of solar in our climate. The cost of the system might have been better spent in the extra cost of heating via the heat pump ( which is not that much for our small pool).

When you say the controller doesn't support priming on high then dropping, do you mean the Goldline+2 speed pump combo? At the moment when the valve turns to send water to the panels the pump has no idea what is happening. If it's on high then fine, otherwise it just doesn't prime properly. What is strange is that it all worked before I had the Enersol system replaced by a slightly larger system with probably more resistance. The extra head was just enough to stop my borderline system from working right.

The VS pump would solve the issue but the cost would be more than the solar system!

 

[pmcd]

You shouldn't have to change the filter if you change the pump.The superflo vs is hard wired but will run on either 110 or 220v. You could wire a plug onto the pump for your 3 prong pump outlet. Just make sure to use 12 gauge wire.

Ok, had a pony panel installed with 220/110v options. So hard wiring or three pronged is now easy! Bought a Super Pump vs 115v which will be hard wired. The Xstream cartridge filter came with a plastic base which also accommodated the Power Matrix two speed pump. Everything then sat on a concrete slab. I never cared for the plastic base that the XStream came with. Can the filter sit directly on the concrete slab with the Super Pump? The new pump has a vertical discharge and so something will have to be done to deal with that. The goal is to get rid of the plastic base of the XStream since the new pump won't fit there ( and the plastic rattled so I want it gone, if possible). If the XStream requires that base them am open to other filtration solutions.