Filter capacity?

[JamesW]

I checked it again. That's correct.

3,500 and 2920 or 2020?

For a three-phase circuit, watts equal volts times amperes times the square root of 3.



Check the voltage between each pair of legs.

These should be the same.

A to B

A to C

B to C.

Check the amperage on each leg A, B and C.

These should be the same.

For a three-phase circuit, watts equal volts times amperes times the square root of 3.

For example, if the voltage is 230 volts and the current is 9.29 amps, then the power is 230 x 9.29 x 1.732 = 3,700 watts.

Check the rotation.

 

[JamesW]

https://www.energy.gov/eere/amo/articles/determining-electric-motor-load-and-efficiency

 

[JPMorgan]

3,500 and 2920 or 2020?

Sorry... 2920

 

[JamesW]

Check the rotation.

 

[JPMorgan]

Can you double check the vault? Maybe take pics from different angles and post them here?

Not really sure where all these pipes are leading to. No one has ever explained it to me. Anything look odd?

 

[proavia]

You may want to determine what all the valves are for and figure out the flow directions. I see some valves with numbers on them. Is there a schematic somewhere? If not, one should be drawn up to help better understand the plumbing.

I can see some valves only partially open. Important to know why they aren't fully open and if they are on the suction side or return side of the system. Additionally, even if those ball valve handles are fully open, sometimes the internal ball isn't and could be restricting the flow.

On an up note, at least there are flow arrows on some of the pipes.

Hopefully @JamesW will chime in shortly as well.

 

[JamesW]

Can you show the back of the motor?

There should be a pop off cover over the shaft.

Remove the shaft cover and see if the shaft is turning clockwise.

When the motor starts or stops, the rotation should be slow enough so that you can see the rotation.

 

[JPMorgan]

Can you show the back of the motor?

There should be a pop off cover over the shaft.

Remove the shaft cover and see if the shaft is turning clockwise.

When the motor starts or stops, the rotation should be slow enough so that you can see the rotation.


Could be tricky, but I can try. The back of the motor is only a short distance in front of the wall. Not sure if I have room to get back there and do what you suggest, but will take a look in the morning. I think I see a shaft spinning on the side of the motor... possibly a cover plate missing that allows me to see that. I can turn the pump off and on a couple of times to see if I can determine if that is the shaft and which way it is spinning.

You may want to determine what all the valves are for and figure out the flow directions. I see some valves with numbers on them. Is there a schematic somewhere? If not, one should be drawn up to help better understand the plumbing.

I can see some valves only partially open. Important to know why they aren't fully open and if they are on the suction side or return side of the system. Additionally, even if those ball valve handles are fully open, sometimes the internal ball isn't and could be restricting the flow.

On an up note, at least there are flow arrows on some of the pipes.

Yes.... once we get our pool service provider situation straightened out I hope to have them explain all this to me so I understand it better. Trying not to deal with our current contracted company because they are pretty awful and I'm pushing to get rid of them. (Examples: never mentioned a word about our insufficient flow rate... told me to talk to the engineer when I raised the issue.... allowed CYA to get to 180 before I arrived here... pretty sure they never tested for it.... sells us a bunch of chemicals we don't need and then won't take them back when I don't use them. Got to go!!!) The company that has worked on the pump seems better.... so far. Hopefully we will continue to be satisfied with them and will hire them and dump the other bozos.

 

[JamesW]

Maybe use your phone to video the shaft from the back so that you can play it back as the motor starts and stops.

Maybe use a mirror behind the pump and then video from the top or side.

Looking in a mirror, the rotation will look like it is counterclockwise.

The shaft cover should pop off easily.

You can also look from the front at the impeller.

The impeller should rotate counterclockwise when looking from the front.

A three phase motor can be wired to rotate either way.

It’s is quite possible that it was installed with reverse rotation.

The impeller still spins, so it will still move water, just less efficiently than if the rotation was correct.

It would explain the weak performance.

 

[JamesW]

It looks like there is a gap that you can look into to see the shaft.

Or, look at the impeller.

 

[JamesW]

What To Do About Air Leak

We just recently opened the outdoor pool at our HOA and I am noticing a lot of air in the system. I can see air bubbles coming from several of the jets (in shallow end of pool) and each time I check the equipment I am bleeding lots of air from the two large filters. Should I be concerned about...

www.troublefreepool.com

Did you ever get this air leak figured out?

 

[JamesW]

The pump should have an arrow on the front that shows the direction of rotation as shown in this picture.

 

[JamesW]

Pump repair completed today. Flow rate has improved, but not where it should be. Pool company seems to be stumped. Flow rate has gone up about 30 gpm, but filter pressure has increased and is now running at 30 psi.

The filter pressure should not go above about 16 psi at full flow, so there might be a problem with the sand or maybe something past the filter is causing a restriction.

Any concern about possible damage to the system with filter pressure running at 25-26?

All are reading about 25 psi.... a little lower on the gauges coming out of the filter.

Filters pressures are about 23 and 24 psi now.

The current pressure is too high for the flow rate.

If you increase the flow from 130 gpm to 167 gpm, the pressure will increase by about 1.65 X.

So, increasing the flow will put the pressure at about 40 psi or higher.

This is too high and you should not increase the flow until you can figure out why the pressure is so high.

I would not want the pressure to be any higher than about 25 psi maximum and 15 to 20 would be much better.

 

[JamesW]

Filters pressures are about 23 and 24 psi now.

Because you have 2 filters, the flow should be half through each, which is about 65 GPM.

We can estimate about 6 feet of head loss for the filter and about 6 feet for the multiport valve at 65 GPM.

That is 12 feet of head loss or about 5 psi.

If the suction is 100 feet of 3” PVC pipe and the return is 100 feet of 3” PVC pipe, then the suction should be about 3.5 feet of head loss (3” Hg) and the return should also be about 3.5 feet for a total of 7 feet or about 3 psi

The total head loss should be about 19 feet or about 8 psi.

24 - 8 = 16 psi of extra pressure.

Maybe the flow is higher than the flow meter is indicating?

I would replace the flow meter and the vacuum gauge.

Maybe put a second flow meter on to see if they are the same.

If the flow is verified, then the system has excessive restriction on the suction and returns.

Verify the rotation of the motor.

 

[JPMorgan]

What To Do About Air Leak

We just recently opened the outdoor pool at our HOA and I am noticing a lot of air in the system. I can see air bubbles coming from several of the jets (in shallow end of pool) and each time I check the equipment I am bleeding lots of air from the two large filters. Should I be concerned about...

www.troublefreepool.com

Did you ever get this air leak figured out?

I has been better recently, but still getting some air. We are closing the pool on Monday, so some of these issues will need to be addressed next year. Pool company technician was out today and I have an update that I will post later.

 

[JPMorgan]

I looked at how the shaft is spinning and it is going clockwise. As I stand at the side on the motor, it spins toward me (which from the back side of the motor would be clockwise). The technician that was here today said he is getting 13.9 amps on one side and 15.4 on the other. (I have no idea what that means, though he tried to explain it to me.) He fixed a bad flow meter which was located on the return line and we got a reading from that flow meter of about 170 gpm. The other flow meter still shows about 140 gpm. He said they should be the same, so he switched them to see what would happen and each flow meter gave the same reading.... switching the location did not change what we were getting from each flow meter. He did note that there is a stretch of 1" pipe after the filter from a T going into 2" pipe downstream (see pics) and said that is likely restricting the flow somewhat. He is having his engineer look into whether it's possible to get 170 gpm flow through that 1" pipe and said, if not, then the flow meter giving the higher reading might be off. Said that sometimes the flow meters are "doctored" to get a higher flow rate, but also said he didn't see any evidence of that. If the 170 gpm is accurate, then the other flow meter must be off and they will try replacing that one. At this point, flow is acceptable if we go by the 170 gpm reading, but unclear why we are getting two different readings.

TBD.... 1) which flow meter is giving the accurate reading; 2) possibly changing stretch of 1" pipe to 2" pipe.

 

[JamesW]

The technician that was here today said he is getting 13.9 amps on one side and 15.4 on the other.

There are three lines, so there should be 3 amperage readings and 3 voltage readings.

What was the voltage?

Check the voltage between each pair of legs.

These should be the same.

A to B

A to C

B to C.

Check the amperage on each leg A, B and C.

These should be the same.

 

[JamesW]

Did the person measure the power or the power factor?

This is why I said that most people do not understand how to properly test 3 phase motors.

 

[JamesW]

Can you show the power switches and breakers?

Where did the person test the current?

 

[JPMorgan]

Check the voltage between each pair of legs.

These should be the same.

A to B

A to C

B to C.

Check the amperage on each leg A, B and C.

These should be the same.

What happens if the voltage is not the same and/or the amperage is not the same? What is the resolution in that case?
I think we are at a point where we need to call in a competent electrician. I have a guy who has done work for me in the past and I have forwarded these comments to him to see if he is capable of testing and answering these questions.