Low pressure/suction after motor replacement

[AZ-Pool-Owner]

Hi all,
Hoping you might have ideas to help me diagnose, let me know if more equipment info needed. Btw, is "pump" synonymous with the motor (?), the basket(?), the plate connecting them(?), all of it?

Originally had a 1hp motor with 1" impeller and it worked great for my setup, have skimmer vac mate attachment for vacuum and also have in ground hot tub. If suction was all pool side, I'd have 12-15 psi on the sand filter gauge (Hayward S311SX) and vacuum would zoom around almost climbing out of the pool so it did clean the walls well. If suction/return was all to the in-ground spa psi would be around 30 and the jets had great pressure without the need for air pump.

Fast forward and "someone" let the pump run dry, it got hot, real hot lol, kinda melted the impeller and motor was screeching. Had the motor setup replaced by company A. Pressure was real low, vacuum barely moved and spa jets just terrible. Guy claims to not know why, mirrored original setup. Turns out he used 3/4" impeller and the motor was rebuilt poorly, loud and almost cyclical, like impeller only threw water every half turn, not constantly.

Now enroll company B to replace. First tried 1hp with 1" impeller, still low pressure, average 10 psi on vacuum, still slow to move around. Then tried 2hp motor with 1.5" impeller, which we expected would increase pressure, but didn't. Guy says it may be my sand filter having 'channels' that the water is flowing through. I replaced the sand maybe 4 years ago. Haven't had any issues until this motor/impeller replacements.

So that's where I'm at now, vacuum is not cleaning entire floor of pool overnight, not even attempting to climb walls, I feel like the pressure is almost half what it should be in most situations. Anyone have an idea what I could inspect or how to get my pressure back up? Variable speed pump was suggested but I don't understand why like for like components aren't functioning the same.

Thanks!!
Dan

 

[ajw22]

Do you have all the parts you have gone through?

Can you give us the motor and impeller part numbers you started with and then tried.

What model pump do you have?

For a pump with the type of meltdown you describe I would have suggested to just replace the whole pump. The volute may have warped from the heat.

 

[1poolman1]

Hi all,
Hoping you might have ideas to help me diagnose, let me know if more equipment info needed. Btw, is "pump" synonymous with the motor (?), the basket(?), the plate connecting them(?), all of it?

Originally had a 1hp motor with 1" impeller and it worked great for my setup, have skimmer vac mate attachment for vacuum and also have in ground hot tub. If suction was all pool side, I'd have 12-15 psi on the sand filter gauge (Hayward S311SX) and vacuum would zoom around almost climbing out of the pool so it did clean the walls well. If suction/return was all to the in-ground spa psi would be around 30 and the jets had great pressure without the need for air pump.

Fast forward and "someone" let the pump run dry, it got hot, real hot lol, kinda melted the impeller and motor was screeching. Had the motor setup replaced by company A. Pressure was real low, vacuum barely moved and spa jets just terrible. Guy claims to not know why, mirrored original setup. Turns out he used 3/4" impeller and the motor was rebuilt poorly, loud and almost cyclical, like impeller only threw water every half turn, not constantly.

Now enroll company B to replace. First tried 1hp with 1" impeller, still low pressure, average 10 psi on vacuum, still slow to move around. Then tried 2hp motor with 1.5" impeller, which we expected would increase pressure, but didn't. Guy says it may be my sand filter having 'channels' that the water is flowing through. I replaced the sand maybe 4 years ago. Haven't had any issues until this motor/impeller replacements.

So that's where I'm at now, vacuum is not cleaning entire floor of pool overnight, not even attempting to climb walls, I feel like the pressure is almost half what it should be in most situations. Anyone have an idea what I could inspect or how to get my pressure back up? Variable speed pump was suggested but I don't understand why like for like components aren't functioning the same.

Thanks!!
Dan

You have an Emerson replacement motor on your ??? pump (no pump manufacturers used Emerson motors in the past). The numbers on your pump may have been misleading. It may have been a 1hp uprated pump which would have had a 3/4hp full-rated impeller in it. When the motor was replaced, the installer probably just looked at the horsepower and not the service factor very common practice even today). Despite a true 1hp replacement motor, it would have been a 3/4hp pump.
A higher horsepower pump can induce "channeling" into a sand filter.
Best thing you could do would be, if you are able, get a VSP like a Pentair Intelliflow/IntelliPro or TriStar in as large a horsepower rating as you can afford and adjust the speed to your pool's requirements.
There could be other viable options, but it would be good to get the model (or a picture) of your current pump posted or in your signature.

 

[AZ-Pool-Owner]

The original diffuser I have a picture with 320-113b on it, I do not have the impeller nor a picture of it unfortunetely, the motor was Emerson K63CXESD-4791, 1hp, 3450 RPM.

I don't have the model of the first "new" motor attempted, there was no label. I do have a picture of the impellers but not the model numbers, see attached "1st impellers" picture, left is what Company A put on, right is what Company B swapped to (1" size).

The new pump motor (2nd attempt) is a Century SQ1202, 2hp, 3450 RPM. The diffuser plate has CI-200PA on it, I have not removed yet to check the impeller but from what I see it's about the same size as the one on the right in that picture. I can remove the diffuser here later to check the actual impeller if necessary.

Thanks much!

 

[1poolman1]

The original diffuser I have a picture with 320-113b on it, I do not have the impeller nor a picture of it unfortunetely, the motor was Emerson K63CXESD-4791, 1hp, 3450 RPM.

I don't have the model of the first "new" motor attempted, there was no label. I do have a picture of the impellers but not the model numbers, see attached "1st impellers" picture, left is what Company A put on, right is what Company B swapped to (1" size).

The new pump motor (2nd attempt) is a Century SQ1202, 2hp, 3450 RPM. The diffuser plate has CI-200PA on it, I have not removed yet to check the impeller but from what I see it's about the same size as the one on the right in that picture. I can remove the diffuser here later to check the actual impeller if necessary.

Thanks much!

Those appear to be StaRite Max-E-Glass 1/DuraGlass 1 impellers. The one on the left seems to be severely damaged (what are those ridges?). The one on the right is a larger-horsepower impeller. What are the numbers on the impellers?
That diffuser was used on 3/4 - 2 hp. Max-E-Glass/DuraGlass pumps. Max-E-Glass were full rated. DuraGlass were uprated. Everything is different now with regard to pump ratings.
Emerson, Century, A.O.Smith, Neptune, are all motor manufacturers. All pump manufacturers buy motors, they don't make them.

 

[AZ-Pool-Owner]

You have an Emerson replacement motor on your ??? pump (no pump manufacturers used Emerson motors in the past). The numbers on your pump may have been misleading. It may have been a 1hp uprated pump which would have had a 3/4hp full-rated impeller in it. When the motor was replaced, the installer probably just looked at the horsepower and not the service factor very common practice even today). Despite a true 1hp replacement motor, it would have been a 3/4hp pump.
A higher horsepower pump can induce "channeling" into a sand filter.
Best thing you could do would be, if you are able, get a VSP like a Pentair Intelliflow/IntelliPro or TriStar in as large a horsepower rating as you can afford and adjust the speed to your pool's requirements.
There could be other viable options, but it would be good to get the model (or a picture) of your current pump posted or in your signature.

Guarantee the motor wasn't original to the whole system. I will get a picture of my equipment posted to my signature, thanks for that suggestion. I hear you on the variable speed... however; I may have just fixed this? I took it all apart to get pics for this thread and when I put it all back together it's working as I would expect. Crazy. Go figures. Maybe a seal issue? I'll update my thread, I may not need anymore assistance but thank you for the reply!

 

[AZ-Pool-Owner]

Guarantee the motor wasn't original to the whole system. I will get a picture of my equipment posted to my signature, thanks for that suggestion. I hear you on the variable speed... however; I may have just fixed this? I took it all apart to get pics for this thread and when I put it all back together it's working as I would expect. Crazy. Go figures. Maybe a seal issue? I'll update my thread, I may not need anymore assistance but thank you for the reply!

Those appear to be StaRite Max-E-Glass 1/DuraGlass 1 impellers. The one on the left seems to be severely damaged (what are those ridges?). The one on the right is a larger-horsepower impeller. What are the numbers on the impellers?
That diffuser was used on 3/4 - 2 hp. Max-E-Glass/DuraGlass pumps. Max-E-Glass were full rated. DuraGlass were uprated. Everything is different now with regard to pump ratings.
Emerson, Century, A.O.Smith, Neptune, are all motor manufacturers. All pump manufacturers buy motors, they don't make them.

That's why I was asking what is the "pump" to you all? The basket? The plate that connects to it? I have all mismatched parts so there is no one answer.

 

[AZ-Pool-Owner]

Might have solved this myself, took everything apart for pictures and when I put it back together I'm getting way better pressure readings and my vacuum is zooming around. May have been a seal issue? Hard to say as I didn't do anything special here. Will update if situation changes! Thanks all!

 

[1poolman1]

Might have solved this myself, took everything apart for pictures and when I put it back together I'm getting way better pressure readings and my vacuum is zooming around. May have been a seal issue? Hard to say as I didn't do anything special here. Will update if situation changes! Thanks all!

Over the years, on several occasions, when a repair didn't seem to work I would take it all apart and do it over, step-by-step, and the problem would usually go away. Why? I don't know, but as long as it was working properly, like yours now is, it didn't matter. Apparently it was operator error. Those old StaRite pumps are workhorses. The 1/2hp models were still made until about 5 years ago, 30+ year run.

 

[1poolman1]

That's why I was asking what is the "pump" to you all? The basket? The plate that connects to it? I have all mismatched parts so there is no one answer.

Put all these parts together and you have your pump, an assembly of all of this. They are not mismatched as the only variable, besides impeller horsepower, can be the motor manufacturer. Doesn't matter who made the motor, it is still a StaRite Max-E 1 or DuraGlass 1. This is actually a parts list for a DuraGlass 1.