New Pump, Running Hot

[gigi747]

I just had an EcoPump EP6 installed Friday, however when it runs on it's high speed, it gets very hot and you can smell the windings heating up... Has anyone had trouble with these AO Smith motors? It runs fine and nice and cool on low speed...

My timer is a mechanical Intermatic with a SPDT switch after it for the Hi/Low. I picked up the 3-way switch from Home Depot, and it is rated for 240v/20 amps... I still have to look over all the wiring and connections etc.

My first guess would be a bad connection somewhere, bad timer (almost 20 years old-however the old pump worked just fine on it) corroded wire somewhere, or maybe the AO Smith pump is actually bad...

I still have to look everything over, but wanted to get some input on the AO Smith motors and if anyone had problems with them.

Thanks!

 

[happyheathen]

First - if you can smell a motor, turn it off - the thing is drawing more current than it was intended to.

My first thought would be to ensure that any possible configuration issues (voltage, what ever else could be set more than one way are all set to the same option (don't configure for 208 and feed 220 for instance (208 is usually 3-phase; 220 is single).
If the motor's internal wiring is properly configured, the next thing is to check and at least remove from list of possible problems:
That capacitor on your motor may be a "start" only or a "start and run"; the former is not involved in the running - it simply induces a phase shift so the armature winding is out of alignment with the field - it tries to get aligned by turning - hence "start".
I had not heard of "start and run" until my HVAC blower needed a new one. No idea their function - but they remain in the line while operating - remove the cover. Does the capacitor show heat damage? Run just long enough to determine if the smell is from the capacitor or the innards of the motor.
Look for a short to ground - a major one should blow the circuit breaker - a tiny one might draw just enough excess current through the windings to heat them.

Has any part of the motor (besides the electrical panel, duh) been opened? A foreign item might be the problem.

If this had been a common issue, you would probably not have needed to ask.

I have no knowledge of that pump or its maker, but A. O. Smith owns the pool pump market - the problem is almost certainly with your install.
Good luck!

 

[gigi747]

Thanks for the advice!

She's been shutdown, looks like I get to work when I get home from work, haha!

I'll report my findings!

Cheers

 

[happyheathen]

Quick thought:

I don't know how much you know about capacitors, so lesson 1 in "how to Safely handle a capacitor":
Those things store electricity and discharge it only when told to. Some can hold that charge even when the device has been turned off.

ALWAYS SHORT A CAPACITOR BEFORE REMOVING IT!

This is usually done by placing a screwdriver across the terminals. If your screwdriver has the shaft all the through the handle, be careful how you hold it.

 

[gigi747]

So I double checked all the wiring to the motor tonight.
Hot 1 is going to my SPDT switch, which in turn is connected to A and L1 of my motor.
Hot 2 is going to L2 of my motor.
And ground is going to ground.

I measured the voltage between each hot and I'm getting ~235 (each legs reads ~118)
When the motor is on low, each hot wire reads ~1.5a
When the motor is on high, hot #1 reads ~8.5a, and hot #2 reads ~8.5a

So I swapped out the circuit breaker for a new 20 amp. I checked the connections at the pump, all were secure. The capacitor looked fine(thanks for the reminder). I started it back up, no smell or heat for about ten minutes. After about 15 minutes, the pump housing was very hot to the touch, almost hot enough to make you pull your hand off of, and it was starting to smell.

So it's only drawing the 8.5 amps that it is supposed to, but still getting hot. Maybe I'm overreacting here, I didn't think that your motor should get too hot to touch. However after some forum searching, in some instances this is normal. My motor has class F insulation, which is rated to 311*F. My old motor had class B insulation. Perhaps the smell I am smelling and just a hot motor and I'm not used to it?

I guess here's my excuse to buy an infrared thermometer...

 

[happyheathen]

I know nothing about pumps; my father was in the motor building business (wrote specs - a job automated about 10 seconds after he retired).
Before accepting any motor running like that, contact the pump manufacturer - I would think if something that out of the ordinary is intentional, there would have been a large, red warning - pools attract children, most of whom have little understanding of lacquer insulation and motor windings, but do tend to poke and prod everything they see. I am assuming the pump is in an open area with plenty of air circulation.
Who sold, who installed, what do they say? Ask for contact info of other owners.

The fact that the insulation is still good will be of little consolation if a winding shorts - that smell is the lacquer (or whatever) used to insulate the winding's wire (the wire never moves; mechanical abrasion is not an issue).

Found an extended discussion of the product and technology - I just skimmed it. You might want to take a look:
http://forums.thathomesite.com/forums/l ... 01.html?16

Talk to A.O. Smith - see if they have heard from other owners.

 

[scooperhsd]

what is the size of the wiring that you ar using to connect the pump to the powerpanel ? If it's too small, that can cause heatup issues. I'd receommend at least 12 guage wire.

 

[gigi747]

I had a local pool store install it. I'm not a fan of pool stores/service men so I'm not going to bother with them. The wire is 12 gauge and the pump is ~4' from my timer box. The pump is outside and protected from the elements and has proper ventilation.

I called EcoPump, they said they have never seen those pumps gets hot.. Their "technical support guy" sounded more like a salesman than an electrician or technician.

I emailed the Centurion division of AO Smith, their response was to call one of their 'authorized service centers'

 

[Bama Rambler]

After about 15 minutes, the pump housing was very hot to the touch, almost hot enough to make you pull your hand off of, and it was starting to smell.

If you can force yourself to hold your hand on it for 8 seconds it's less than 150ºF. If it's less than 150ºF then it's fine.

 

[mikexyz123]

I have the exact issue. Installed new 1.5 HP AO Smith pump for a Hayward SuperII pump. Old one started making all kinds of noise and when I took apart, impeller was melted onto shaft.

Ordered new pump with same specs. Installed it fine, water moves great, very quiet.... but motor casing is HOT. I can hold my hand on for 8 secs, but barely.

Had electrician check for 230 volts (236), wired correctly. Took apart again to insure impeller moves freely. Snaked out drain side pipe incase of clog (no). But back together again. Still hot. :grrrr:

I read in another post that a smaller impeller fixed the problem. I'm worried if I leave as is I'll end up burning up the motor (and melting impeller.) Am I just being paranoid? Any other ideas?

I'm new to site and think it's GREAT!

 

[JohnT]

I have the exact issue. Installed new 1.5 HP AO Smith pump for a Hayward SuperII pump. Old one started making all kinds of noise and when I took apart, impeller was melted onto shaft.

Ordered new pump with same specs. Installed it fine, water moves great, very quiet.... but motor casing is HOT. I can hold my hand on for 8 secs, but barely.

Had electrician check for 230 volts (236), wired correctly. Took apart again to insure impeller moves freely. Snaked out drain side pipe incase of clog (no). But back together again. Still hot. :grrrr:

I read in another post that a smaller impeller fixed the problem. I'm worried if I leave as is I'll end up burning up the motor (and melting impeller.) Am I just being paranoid? Any other ideas?

I'm new to site and think it's GREAT!

Perfectly normal. 8 seconds is longer than I'd keep my hand on my pump.

 

[gigi747]

Thanks for all the input guys, I appreciate it!