Dynamo Pump Humming

Jul 22, 2011
94
This is going to start off like the typical "my pump is humming" threads, but wondering if my issue is a bit different.

pump runs almost 24x7 on low, and then i run on high for a few hours each day. went to go backflush the other day, turned pump off, switched filter gears, reached down to switch pump back on, hums galore. i said GREAT... here we go again! this is my 3rd pump in 5yrs... same pentair dynamo 2 spd pump... i popped the cover off and can spin it up manually by hand and it carries on as normal. but i kill the power, no go... i ordered a replacement capacitor. came in saturday, put it on sunday AM and nada... same thing... just hums. finally electrician friend comes over and tells me nothing is wrong with either cap, it's the fact the cap is not getting power. only thing we can think of is to crack open the casing and see if the wires are fried or corroded... pentair says i'm SOL and outta warranty, so any advice is greatly appreciated!!!

thanks!
 
Well, since you're high-and-dry on your warranty, why not open 'er up? You might be able to get it running (or at least limping...) for cheap/free.

Worst-case scenario, you're buying a new pump motor anyhow.

certainly... but i can manually get things going now with a little screw driver spin, so i don't want to mess things up completely without know exactly something to look for... not really in a position to purchase another pump just yet... so i'd rather have to work things manually as opposed to have a dead pump all around by pokin around where i shouldn't be... lol
 
Since it's not the capacitor, I'd suspect the centrifugal switch and/or contacts.
Can you see the switch when you have the end cover removed. There should be a couple of springs on the sides of the shaft.
 
Since it's not the capacitor, I'd suspect the centrifugal switch and/or contacts.
Can you see the switch when you have the end cover removed. There should be a couple of springs on the sides of the shaft.

i'll have to go out there and look to see if i can find what you're referring to. not sure what i'm looking for, but i'll see if i can find some springs without taking it completely apart...
 
That looks like the 'switchless' design. There are some connections behind the terminal plate, but you'd most likely have to remove the bell end to get to them, so it's up to you if you want to try that. The problem with doing that is that you will possibly break one or more of the thru-bolts off when trying to remove them.
 
That looks like the 'switchless' design. There are some connections behind the terminal plate, but you'd most likely have to remove the bell end to get to them, so it's up to you if you want to try that. The problem with doing that is that you will possibly break one or more of the thru-bolts off when trying to remove them.

well that doesn't sound like fun... is there any kind of wiring diagram or breakdown of parts i could find somewhere? from what pentair said, these are AO smith motors... but can't find much in the way of a breakdown anywhere...
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.