Pump Flow Fluctuations

[ca1ore]

I am having some issues with slight flow variations from my main pump and cannot work out why. I'd likely not even notice except it mucks with the setting of my herbie-style drains. Previously I just thought it was probably that my old pump (PW 150) was failing, but upon purchasing a new one, same problem. Pump is plugged into an EB8 on my Apex.

Anybody have any thoughts on what is going on? I know that the power into my house does vary from about 112 to 117 volts (I know this because I have a power conditioner on my stereo system) - not an electrical expert, but could this be the reason?

 

[Vinny Kreyling]

Limited electrical knowledge here but if you add more gas the engine will run faster.
Add more current the same should apply.

 

[mcgyvr]

How are you determining you are having fluctuations?
A voltage range delta of 5V shouldn't have much if any effect on it.. But it will have some on that type of pump as its directly line powered..

could be cavitation on the inlet and many other things depending on the specifics of your plumbing,etc..

 

[Vinny Kreyling]

I run a DC pump & my Herbie does NOT stay constant all the time either.

 

[ca1ore]

How are you determining you are having fluctuations?
A voltage range delta of 5V shouldn't have much if any effect on it.. But it will have some on that type of pump as its directly line powered..

could be cavitation on the inlet and many other things depending on the specifics of your plumbing,etc..

I'm basing my comment on an audiophile power conditioner that monitors and displays voltage. Rather a 'stab in the dark' as I have explored and eliminated all of the usual suspects - at least, all the ones I could think of. It's very strange.

 

[Vinny Kreyling]

Simon,
ON A DC PUMP, I was told - running reactors can cause this sympton.
Any restriction when reactors either start to clog or cause resistance can cause a flow difference.
Like adding head pressure.

 

[HippieSmell]

I would increase the airflow getting into the drain and see if that fixes it. Too much air restriction can cause fluctuations.

 

[ca1ore]

Simon,
ON A DC PUMP, I was told - running reactors can cause this sympton.
Any restriction when reactors either start to clog or cause resistance can cause a flow difference.
Like adding head pressure.

Good thought, but I don't run any reactors off the main pump for precisely that reason. I think I am going to pull it off the energy bar to see if that makes any kind of difference. Flow tends to be slightly lower at night; probably only 10 or so gph, but enough that my siphon drain sucks air.

 

[ca1ore]

Gave up trying to workout why and just reconfigured my two corner overflows as dual, independent herbies. Required moving to an over the rim return, but the fluctuating flow now is modulated by the dual emergencies.

 

[tkeracer619]

AC motors rpm are not determined by the voltage but the hz. The formula for rpm in a single phase motor is (Hz x 60 x 2)/ Number of poles. Your voltage fluctuation wouldn't cause it.

 

[jonwright]

Atmospheric pressure will mess around with skimmers and presumably water levels. I can almost predict if the barometric pressure is rising or not by the level of water in my overflow with a herbie setup.

I also experience this with my LifeReef skimmer. The level goes up, then back down and it seems to coincide with the pump as far as I can tell (which isn't much). I can't decide what's doing it because I can definitely hear more air go through - so I'm not sure if it's cause or effect.