Pump overheating

RRich · Postby **RRich** » Sun 31 May, 2009 16:50

When I purchased a Kreepy Krauly about six to seven years ago and started performing my own pool maintenance, I started noticing that my filter pressure normally ran no lower than about 18 PSI â€“ sometimes after acid-washing the grids it ran as low as 15 PSI, but only for a few days and never ever lower than 15 and required sometimes weekly backwashing. Sometimes, even backwashing and manually cleaning the filter grids wouldn't bring the pressure down.

At 20 PSI, the Kreepy slows to a mere crawl and stops working all together, though the skimmer will continue to work for a few days with the Kreepy disconnected. Over the years, I've inquired with my local pool supply/service shop several times and was never given a real explanation or solution for the high pressure. Recently, while my pump and motor were in the shop for repair/replacement, I mentioned this issue again and pointed out that the return line was only one inch pipe, as was pointed out to me recently when one of the technicians had been at the house to investigate the problem with the motor. He pointed out that my water return line from the filter to the pool was only one inch pipe, while the line from the pool to the pump was two or 2.5 inchs. He explained how the whole filtration process works and that the difference in pipe size was causing an inordinant amount of pressure to build up in the filter tank, as water couldn't flow out at the appropriate rate in comparison to the rate being pumped in.

The owner suggested replacing the normal-sized pump impeller with a smaller one (I don't remember the sizes). The impeller was changed out and that seemed to solve the problem, as the pressure recently has been as low as 9 PSI. It's very noisy though, especially with the Kreepy Krauly connected, but I'm not sure whether the noise is directly related to the smaller impeller or the new pump motor or other. For now reducing the impeller size seems to have solved my pressure problem and don't know yet whether this change will cause some other filtration component to be out of balance.

grmcgee · Postby **grmcgee** » Sun 21 Jun, 2009 18:33

I have read this forum and many others about pool pumps overheating. I have a Hayward Superpump on a 21,000 gal inground pool. The motor is UST1102 (115/230 volts, 1 HP). This setup ran flawlessly for over 12 years, maybe 15 (I am the second owner). My normal mode of pump operation during summer is 24/7. The pump is turned off for only short periods to switch filter modes or start/stop auto cleaner. Last year I had to replace the motor capacitor, after which the motor ran great all summer. This year after about a week of normal operation, the motor has started overheating and cutting off. It runs about 2-4 hours before the thermal switch cuts off operation. There is also a smell of "hot wires" that has never occurred before. After cooling for a few hours, the motor will run normally again for a few more hours. It has always run somewhat hot, but it has never been cut off by the thermal switch until now. I have not checked the voltage/amperage yet, but it doesn't seem likely that is the problem since the exact same setup (an isolated electrical circuit) has run great for so many years. Also, the motor is inside a pump house, protected from the weather with nothing blocking the surrounding air. So the questions to you experts are: Does this mean that my motor is wearing out and I will need to replace it soon? Or is there a chance that I have a power (or other) problem that can be corrected? In other words, it is worth the time to do diagnostics, or should I go ahead and spring for a new motor?

ThisSucks · Postby **ThisSucks** » Wed 17 Feb, 2010 20:55

SO my pool pump would only suck at bout 50%. I dug out the line to find a major bend in the flex pvc and a major crack. Fixed the line. Now it sucks at 100% but the motor overheats at about 4 min. The extra load i'm guesing is causing it. Motor never overheated when it ran at 50%. I even ran it 24 hours straight and no problem. So problem solving time. Asked around, checked online. Concensus was that the motor was bad due to running at half pull for so long. REplaced the motor. And guess what, same problem. Overheated in like 3 minutes. So now i'm debating whether it is the filter or i have a clogged line which is causeing the load. I don't think its the wiring since the pump ran for months fine at half pull. Anyone have any ideas? thanks

poolpumpguy · Postby **poolpumpguy** » Thu 18 Feb, 2010 13:37

stevek wrote:I just replaced my 3/4 hp hayward today with a 3/4 AO and having the same problem. In additon to this the pump is cycling(?), turning off and on but not like when it over heats and changes speeds. Any suggestions? The wiring was fine for the last 3/4 pump. Should I look at replacing it or is it a pump issue?

Steve

if it is a northstar by hayward that motor is almost a 1.5 hp. you must check the service factor of the old motor. or check your voltage with a meter. a 3/4 could have be set for 115 v. new motors from factory are set for 230 volts
this is a hayward trick they used to make you think you are getting a 3/4 pump that looked as if it pumped as much water as a 1 1/2 pump.. if you don't have the old motor you will need to ID the impeller and start from there.. this is what it sounds like to me..... or bring your pump in to your local pool pump motor repair guy with free motor testing and have him help you .. good luck

waspa · Postby **waspa** » Fri 05 Mar, 2010 22:14

Hi there, I am new to this forum and I don't have a pool. I have a Caldera Hot Tub and we are having the same problem with our pump motor overheating. It is a sta-rite 2 1/3 hp, it will run great for a little while and then shut off until it cools sown then will come back on. A few days ago my husband went out to heat it up and the control panel was displaying the "flo" and the temp read at 50 degrees. We initially thought it was the heater, but it tested fine. I talked to a hot tub tech and was told that there is a thermal couple in the motor that is probably bad. I can not find this particular part and all the schematics of this particular pump I can not find this part. Do we need to replace the whole motor? Can we just replace that piece and if so, where is it???? Any suggestions? Any other ideas on what else could be causing this problem?
Thanks

Guest · Postby **Guest** » Sat 14 May, 2011 22:13

We replaced the motor twice and it is still overheating. Now what?

nickiface · Postby **nickiface** » Sun 15 May, 2011 08:34

I just bought hayward
super ii 3/4 horsepower, runs very well for 5 minutes the burnt smell, trips off .
Brand new motor from ao smith, i put new impeller seals and o-rings, no better.
Can i get a new one! It's from inyo discount pool parts store

LoopZilla · Postby **LoopZilla** » Tue 05 Jul, 2011 16:45

OK,

Same issue, new 3/4HP motor overheating. Motor is a replacement for an existing Hayward installation, which I have replaced twice before.

Things I know:
- New seal, new impeller & impeller housing
- Motor is wired for 240V
- Voltage at motor terminals is 236V, 119V on each leg measured to ground, measured under pumping load so no significant voltage drop
- Uncoupled amps are 3.25 on each 120V leg at the pump terminals, dry pump pulls same, wet pump pulls 8.6A on each leg.
- No plumbing changes, water is flowing like it has for the last 12 years
- External gas water pump used to 'clear' the lines, both inlet from drain and strainer, and through output - nothing showed up

Any ideas?

Postby **czechmate** » Tue 05 Jul, 2011 19:56

You should pull around 4 amp running current on 3/4HP motor at 240V fully loaded. Burning smell shows usually blown capacitor. Overloaded tripping motor, like when your pump freezes in winter is not smelling, just warms up and trips. You pulling current that would run a 2HP motor. It would suggest, that probably the running capacitor phase is not electrically in correct angle. I would ask dealer for a replacement.

LoopZilla · Postby **LoopZilla** » Wed 06 Jul, 2011 10:30

I agree, the motor seems to be pulling too many amps. But, I think I can effectively rule out the power supply, because it is delivering those amps, and at the correct voltage.

I removed the motor (again) and had my dealer give me another new motor to try. Same results, so I can rule out a defective motor from the manufacturer.

While I was in there, I replaced the seal (again) and made sure there was no evidence of abrasion on the impeller or housing. Spindle with impeller turn easily with no weird noises.

The internal cooling fan is indeed pumping out hot air from the rear vent when the motor is running.

Is this motor under-rated at 3/4 HP? Or, was the original Hayward over rated? The Hayward installation manual for the Super II actually states a 10A draw for the 3/4HP version on 230V...

I don't have a tach or flow meter, but I think it is turning at the spec RPM.

What in the system could have changed to create this issue? The motor is the ONLY factor that is new.

Any additional assistance would be greatly appreciated.

Postby **czechmate** » Thu 07 Jul, 2011 08:05

I have the same size pool and running 1.5HP motor on the old Swimquip XL pump. Have been told several times it is little beef up, that 1HP should be fine.
The backpressure on the filter would indicate if it is under strain. Up to 20psi is pretty normal. Mine run on fresh DE fill around 12psi. I never let it gain more than 6-7 PSI. Then I bump it and add a some DE back.
It will clear out some debris from overhanging oleandra blossoms' that would rot in the filter. and shorten the cleaning cycle again.
DE is not cheap, but electricity on longer cycle is worse.
Plus running pump extra 3 hours in a 100 degree weather is not helping the motor life.
I may well be, that 21000 gal pool should have at least 1HP motor.
It is all about the the volume draw and power to push thru the dirty filter, to run system more efficiently.

James Nagle · Postby **James Nagle** » Tue 12 Jul, 2011 17:23

Well guys I was looking on here trying to figure out why my pump was doing the exact same thing and I figured it out (for my pump anyway)... The motor has a centrifugal switch inside the back cover that stays engaged while starting the motor and then once started and the shaft starts spinning, it disengages. Mine APPEARED to disengage upon starting but apparently did not thus overheating the motor. I bent the contacts apart a little more and it is working just fine now. Hopefully this helps someone else.

Wirenut Bill · Postby **Wirenut Bill** » Tue 09 Aug, 2011 15:06

I have an old (15 yr?) AO Smith motor that recently started doing the cycling on and off thing. It gets too hot to touch even when disconnected from the pump, so it's time to replace it. Checked the capacitor & centrifugal switch to no avail.

Something did come to mind, though. I have recently replaced the sand in my filter. When I did, the guy at the pool store said to use about 20% less than the filter manual called for. He said it would work as well, but be less strain on the pump. He may have been right. I used 100%. My motor is "toast".

patriciathore · Postby **patriciathore** » Tue 16 Aug, 2011 04:18

To avoid this happen again, you must check your pumps once in a while. Its a must to all swimming pool owners.

Guest · Postby **Guest** » Sun 04 Dec, 2011 02:28

grmcgee wrote:I have read this forum and many others about pool pumps overheating. I have a Hayward Superpump on a 21,000 gal inground pool. The motor is UST1102 (115/230 volts, 1 HP). This setup ran flawlessly for over 12 years, maybe 15 (I am the second owner). My normal mode of pump operation during summer is 24/7. The pump is turned off for only short periods to switch filter modes or start/stop auto cleaner. Last year I had to replace the motor capacitor, after which the motor ran great all summer. This year after about a week of normal operation, the motor has started overheating and cutting off. It runs about 2-4 hours before the thermal switch cuts off operation. There is also a smell of "hot wires" that has never occurred before. After cooling for a few hours, the motor will run normally again for a few more hours. It has always run somewhat hot, but it has never been cut off by the thermal switch until now. I have not checked the voltage/amperage yet, but it doesn't seem likely that is the problem since the exact same setup (an isolated electrical circuit) has run great for so many years. Also, the motor is inside a pump house, protected from the weather with nothing blocking the surrounding air. So the questions to you experts are: Does this mean that my motor is wearing out and I will need to replace it soon? Or is there a chance that I have a power (or other) problem that can be corrected? In other words, it is worth the time to do diagnostics, or should I go ahead and spring for a new motor?