Our spa has begun making a noise that I think means I need to spend lots of money. As the motor runs to heat it, it occasionally makes what I can only call a groaning noise, audible from 25 yards away. It sounds like it’s overloaded, and is heating up pretty noticeably. After a while, it trips the breaker.
I oiled the rear (I think it’s a plain) bearing; the front’s got no oil feed. Possible explanations:
1. Bearing failure, but then wouldn’t it be noisy all the time?
2. Something caught in pump (unlikely; there’s a filter upstream from the pump).
3. Windings failing, but, again, wouldn’t it be noisy all the time?
Any explanations I’m missing? I’d rather not spend lord knows what on replacing the motor and pump if it’s some simple explanation.
Bill Houghton
Replies
Find out the amperage reading on the motor and see what it is. Realistically, onces it starts making noises like this you will be pulling it out for service. The amperage reading at least lets you know how hard, electrically, it is working. In most cases the new motor is less than a rebuild and it goes back in quicker. If it is a cheap motor most likely the front oilite bronze bushing is the problem. No real way to get to it without dissassembly. Even then who knows how long it will last. As a last comment, check the input voltage when you check the amperage.
Well, it's either the pump/motor or the piping. If the piping is plugged the pump would be starved for water. That would sound like a rattle, with an increase in pitch, more than a groan. Does the flow drop off when it makes the noise? You could also be sucking air if the suction piping is cracked. The sounds for sucking air and for blocked flow are similar.
If it's not that, the pump/motor has to come out anyway. You could inspect it better on the bench and find the problem. Taking amperage readings before pulling it is a really good idea. If you can get it when it's groaning, and when it's not, that would be useful information. If the amperage goes up when it makes the noise, that would suggest additional load on the pump, like bad bearings. If the amperage went down when it made the noise, it would suggest lessening load, such as restricted suction, or the impeller loose on the shaft.
Front seal and / or retainer letting you know that it's time is just about up and it's leaving and gonna take the bearing with it.
This is usually the reason for the noise. Not always but most often.
Change both bearings along with the seal and retainer. Repair the pump before the whole unit is history and you get into serious money.
Who ever invented work didn't know how to fish....