New Pool Pump Motor Overheating

Scberniard

Member
Aug 28, 2020
7
Baton Rouge, Louisiana
I recently switched out my booster pump motor (like for like). Century 2.5 HP 230V. The existing motor was old (not sure how old because I purchased the home 1 1/2 years ago) and was blowing start capacitors. After three capacitors I went ahead and switched out the motor as it seemed the old one had reached the end of its life. I never had any issues with the old one besides the start capacitor. After hooking up the new one, it fired right up and running great, but is quickly overheating and shutting off (I haven't timed it, but I'd guess 30 min-1 hr). Nothing electrically has changed, but I did test it and I'm getting the correct voltage. Additionally, after purchasing the new motor and it overheating, I was able to switch it out for another new one and still having the same issue.

Is there any reason why replacing the same exact motor would begin to overheat?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
27,847
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Post pics of the motor data plate.

What model pump is the motor attached to? Post pics of all labels on the wet end of the pump.
 

JamesW

TFP Expert
Mar 2, 2011
26,975
I did test it and I'm getting the correct voltage.
What is the exact voltage that you measured?

What is the voltage before the pump starts and what is the voltage when the pump is turned on?

Check the current (amperage).

If you don't have a clamp ammeter, you can get one.

Can you show the whole system including the breaker and switch that go to the pump?

What is the impeller part number?

 

drsipe

Gold Supporter
Jul 24, 2020
163
Middletown, Pennsylvania
Pool Size
24500
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-60 Plus
When you changed the motor, did you change the seals?

If you did change the seals, but you did not get them seated right (or whenever I bought off-brand seals) the shaft seals can be a little tight.

As a test, you could separate the pump from the motor and perform a motor test run. If the bare motor runs without overheating, then I would replace the seals.

If the motor is overheating when operating bare (without a pump attached), I would open the motor cap and see if the fan is spinning when the motor runs. I've never seen this on a pool pump motor, but I've worked in industry for years and I've seen pumps straight out of the motor shop, that the fan was not properly attached.
 

Scberniard

Member
Aug 28, 2020
7
Baton Rouge, Louisiana
When you changed the motor, did you change the seals?

If you did change the seals, but you did not get them seated right (or whenever I bought off-brand seals) the shaft seals can be a little tight.

As a test, you could separate the pump from the motor and perform a motor test run. If the bare motor runs without overheating, then I would replace the seals.

If the motor is overheating when operating bare (without a pump attached), I would open the motor cap and see if the fan is spinning when the motor runs. I've never seen this on a pool pump motor, but I've worked in industry for years and I've seen pumps straight out of the motor shop, that the fan was not properly attached.
Ok, thanks. Yes, I replaced the seals on both of the new motors. I'll give it a test run and see what happens. I have noticed that the old motor shaft spins easier than the new ones (just spinning it by hand without the seal).
 

Scberniard

Member
Aug 28, 2020
7
Baton Rouge, Louisiana
What is the exact voltage that you measured?

What is the voltage before the pump starts and what is the voltage when the pump is turned on?

Check the current (amperage).

If you don't have a clamp ammeter, you can get one.

Can you show the whole system including the breaker and switch that go to the pump?

What is the impeller part number?

I pulled 245 volts before the pump starts and 240 when the pump is on. I don't have a clamp anmeter, but I will look into getting one.

I took the impeller off, but I could not find a part number on the actual impeller. I was able to get the diffuser part number and I believe that the impeller part # is 35-5315 (Pac Fab).

A picture of the breaker is attached. Thanks for the assistance.
 

Attachments

  • Breaker.jpg
    Breaker.jpg
    74.6 KB · Views: 1

JamesW

TFP Expert
Mar 2, 2011
26,975
See what the amp draw is.

Can you spin the impeller and shaft easily?

Can you show the whole back of the motor where the wires connect?
 

Scberniard

Member
Aug 28, 2020
7
Baton Rouge, Louisiana
See what the amp draw is.

Can you spin the impeller and shaft easily?

Can you show the whole back of the motor where the wires connect?
Ok, I will get the amp draw.

Yes, the impeller/shaft can spin easily. However, when spinning the old shaft compared to the new (all without seals or anything attached), the new ones do not spin as freely. They spin smooth, but not as easily when turning by hand (both new ones feel exactly the same).

I know it's not exactly what you're asking for, but I have a picture of the old wiring attached (I currently have the motor unhooked to get the impeller #). The old/new pump motors are exactly the same and the wiring is identical.

Thanks
 

Attachments

  • Wiring.jpg
    Wiring.jpg
    92.5 KB · Views: 3
Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.