I installed a new Pentair Superflo (1hp) yesterday. Had some initial priming problems, but it primed fine this morning and water circulates well. But only for about a minute--then the pump shuts off. It stays off for a minute or two, then comes back on. This only happens on the high setting; it runs on low fine. Doesn't flip the breaker. It acts like it is overheating and flips some kind of shutoff, but it happens after 1 minute max (including first thing in the morning) and the motor doesn't feel hot at all. The hp on this motor is lower than the one it is replacing, but I can't imagine that would make it strain more somehow (again, runs fine on the low setting). Voltage to the pump is ~240. Any help would be greatly appreciated!
New two-speed pump runs fine on low, shuts off on high
- Thread starter erik in tucson
- Start date
Did you replace the entire pump or just the motor on your old pump?
Is the wiring correct?
Is the wiring correct?
I replaced the entire pump (motor and wet half--bought new as a single unit). I think the wiring is correct; it seems pretty straightforward: one load wire to 1, one load wire to the toggle switch (which has wires going to 2 and 3) as in the attached image:
It definitely seems like some kind of internal overload relay is getting thrown, but I can't imagine why. Although this pump is smaller than the old one (1 hp, sf 1.25 versus 1.5 hp, sf ~1.5), it does seem to be moving water through the system at the same speed, but not more/faster. Can you imagine anything I did wrong with the wiring? Having played around with it some more this morning, I'd say my original estimates were a bit off: it runs for ~30 sec, then shuts off for 2-3 min.
It definitely seems like some kind of internal overload relay is getting thrown, but I can't imagine why. Although this pump is smaller than the old one (1 hp, sf 1.25 versus 1.5 hp, sf ~1.5), it does seem to be moving water through the system at the same speed, but not more/faster. Can you imagine anything I did wrong with the wiring? Having played around with it some more this morning, I'd say my original estimates were a bit off: it runs for ~30 sec, then shuts off for 2-3 min.
It does sound like a thermal switch being thrown, but I would think the motor would be very hot to cause that to happen. I had on doing that and the label was yellowing and it smelled like it was burning.
Did you check the actual voltage at the motor? I am kind of grasping at straws.
I suppose there is the possibility that you got a bad motor.
Did you check the actual voltage at the motor? I am kind of grasping at straws.
I suppose there is the possibility that you got a bad motor.
I haven't checked voltage at the motor yet (hoping to avoid working in that tight space again!), but I'll check that next. Would voltage in the low 240s be an issue if the pump label states a 208-230 range? Is there any kind of shut-off switch other than a thermal one? I agree that it couldn't possibly be truly overheating. Thanks for the help on this.
243V at the motor (244 at the timer). Just ran it on high with the back panel off--same result (ran for 20-30 seconds, then shut off). No burning smells; connections look tight. No wires rubbing the shaft or anything like that.
n240sxguy
Well-known member
Sounds like you just got a bad one. That thermal overload is just an automatic breaker basically. Just like all manufactured things; every once in a while you get a bad one.
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Thought I'd give a final update for anyone with similar issues. Pentair sent a tech out to make sure the installation was done correctly so the warranty would still be valid. It was. He replaced the bad motor and everything has run fine in the ~2 months since. Simply a bad motor out-of-the-box. Never heard back from Pentair with any details. Thanks for the help everyone!