POOL PUMP MOTOR CONTROL
POOL PUMP MOTOR CONTROL
(OP)
Hi Guys,
I got a Pentair Wwhisperflo in ground pool pump for free from a friend and mounted it up to my above ground pool. It filters great and has a pretty good turnover rate on the water but there is one issue, the motor is too powerful when it comes to hooking up the vacuum. Once the vacuum is hooked up, the pump exceeds the flow capacity of the vacuum and it begins to suck air through the pump basket lid. I'm wondering if there is a safe way to knock back the speed on the motor. I'm writing up this thread while I'm at work so I don't have the nameplate info from the motor in front of me, but I'll update the thread with that info once I get home this evening. It is connected to a 120V residential outlet though. Any ideas you guys have would be great, I've been investigating a VFD but I really only need two speeds out it, not "infinitely variable" speed. Thanks Guys!
I got a Pentair Wwhisperflo in ground pool pump for free from a friend and mounted it up to my above ground pool. It filters great and has a pretty good turnover rate on the water but there is one issue, the motor is too powerful when it comes to hooking up the vacuum. Once the vacuum is hooked up, the pump exceeds the flow capacity of the vacuum and it begins to suck air through the pump basket lid. I'm wondering if there is a safe way to knock back the speed on the motor. I'm writing up this thread while I'm at work so I don't have the nameplate info from the motor in front of me, but I'll update the thread with that info once I get home this evening. It is connected to a 120V residential outlet though. Any ideas you guys have would be great, I've been investigating a VFD but I really only need two speeds out it, not "infinitely variable" speed. Thanks Guys!





RE: POOL PUMP MOTOR CONTROL
There is no practical way of varying the speed of a standard 120V motor. SOME more modern pool pump motors are now coming with a VFD built into the motor itself, ie the motor is actually 230V 3 phase and they use the VFD along with a "voltage doubler" so that it can accept 120V single phase. But I doubt anyone would "give away" one of those, they are very very expensive and a hot item on places like eBay or Craigslist. It's more likely your friend bought one of those and gave you his older fixed speed version.
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: POOL PUMP MOTOR CONTROL
Don't try to change the speed of the motor, restrict the flow.
With the flow restricted, the motor will use less energy also.
I have seen industrial irrigation pumps that would burn out if they were allowed to pump with too little back pressure.
When we installed them, we used a valve on the discharge to limit the flow to a safe level.
We would use an ammeter to monitor the current while we throttled down the discharge.
Then we would either wire the valve handle in place or remove the valve handle.
Bill
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"Why not the best?"
Jimmy Carter
RE: POOL PUMP MOTOR CONTROL
RE: POOL PUMP MOTOR CONTROL
RE: POOL PUMP MOTOR CONTROL
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: POOL PUMP MOTOR CONTROL
Keith Cress
kcress - http://www.flaminsystems.com
RE: POOL PUMP MOTOR CONTROL
RE: POOL PUMP MOTOR CONTROL
I once had an application where it was not feasible to throttle the flow. An order was given to have the diameter of the impeller reduced. Due to some mix-up, the thickness of the open face impeller was reduced instead of the diameter. That did reduce the flow but loss of flow due to cavitation was so frequent that the impeller was replaced with a new impeller, properly reduced in diameter.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: POOL PUMP MOTOR CONTROL
RE: POOL PUMP MOTOR CONTROL
RE: POOL PUMP MOTOR CONTROL
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: POOL PUMP MOTOR CONTROL
Keith Cress
kcress - http://www.flaminsystems.com
RE: POOL PUMP MOTOR CONTROL
RE: POOL PUMP MOTOR CONTROL
You say you want reduce flow when vacuuming? If you don't want to also reduce flow during normal pool operations then put in a tee with a solenoid valve in one leg you shut-off when doing the maintenance.
BTW I'm not sure what above ground pools have for suction ports but I hope you've checked them for being impossible to pin a swimmer. Seems to have been a lot of those sad accidents lately.
Keith Cress
kcress - http://www.flaminsystems.com
RE: POOL PUMP MOTOR CONTROL