Pump randomly losing efficiency?

[IOnceWasLegend]

I've had this problem persist across two return pumps and it's making me tear my hair out trying to figure it out.

At completely random intervals (ranging from a day or so to several weeks), my return pump (Varios S2) will lose efficiency and flood my sump. When this happens, water level in the overflow box drops and sump raises. This is not caused by:

• My ATO (water level in reservoir stays constant)
• My overflow box (the weirs are clean, and the drain has had no screen on it since I've tried troubleshooting it)
• My drain (drain line is completely clear, gate valve has remained at a constant setting)

So my only answer is the pump. I have no idea if it's a setting on the pump that I'm inadvertently tripping, or if there's something wrong with the pump, but it is driving me up the wall having my ATO alarm go off randomly. However, like I said, this problem has persisted across two return pumps. Any suggestions for how to test this, or should I just get a new pump because I am losing my mind at this.

 

[JVU]

Do you have it connected to a smart controller like Apex? If so, check the coding meticulously to see if anything is tripping an OFF statement or a feed mode. Or if you have it on a smart plug, same idea.

If you don’t have it connected, it might be useful to connect it temporarily so that you can get an instant notification of when it turns off to help with troubleshooting. If you have the newer Apex with power monitoring that can help differentiate between loss of power, pump turning itself off, pump turning itself down, something getting stuck in the pump, etc.

 

[IOnceWasLegend]

Do you have it connected to a smart controller like Apex? If so, check the coding meticulously to see if anything is tripping an OFF statement or a feed mode. Or if you have it on a smart plug, same idea.

If you don’t have it connected, it might be useful to connect it temporarily so that you can get an instant notification of when it turns off to help with troubleshooting. If you have the newer Apex with power monitoring that can help differentiate between loss of power, pump turning itself off, pump turning itself down, something getting stuck in the pump, etc.

Unfortunately I have neither a smart switch nor an Apex available at the moment.

Edit: I also don't think it's the pump turning off so much as losing efficiency. Tank was kept at steady state, until the sump flooded. I turned the pump up to restore water levels in overflow and sump, turned it back down to its lowest setting (the one I've been running it at), and the sump flooded again.

 

[Patio]

lose efficiency

As in shut completely off or pump less water or unknown?

something getting stuck in the pump, etc.

The intake can also get too close to the sump walls and choke itself a little, maybe?

 

[JVU]

When you clean the pump you don’t see any culprits I guess? What Pat said about making sure the intake isn’t against a sump wall is a good thought. And make sure you are using the intake guard that comes with the pump to prevent intake clogging.

 

[IOnceWasLegend]

As in shut completely off or pump less water or unknown?

The intake can also get too close to the sump walls and choke itself a little, maybe?

Pump less water. And the intake was stationary throughout all of this.

When you clean the pump you don’t see any culprits I guess? What Pat said about making sure the intake isn’t against a sump wall is a good thought. And make sure you are using the intake guard that comes with the pump to prevent intake clogging.

I decided to dig down and open up the pump to clean it. I was initially confused how something stuck in the impeller could be the case, because I assumed the reduction in flow would be constant and progressive instead of the seemingly random nature of less flow, then more flow later on, etc.

Assuming made an ass out of me and...well, just me.

Took the pump apart, cleaned a bunch of calcium deposits off the impeller and the housing, and put it back together. The controller threw up an error message when I tried to turn it on. Through research and process of elimination, I figured out that the pump and controller has a safety mechanism that won't turn the pump on if it detects resistance at a given threshold. It'll try again a few seconds later, though.

So what I *think* was happening was that the calcium buildups were causing drag on the impeller. When it built up enough, this would occasionally be able to trigger a pump shutdown. Pump would shut itself off, sump would flood, pump would turn itself on again, this would dislodge the calcium deposit just enough to let the impeller spin, but at a lower efficiency that didn't *quite* trigger the shutoff. This would explain the random nature of the sump flooding and the inconsistent flow, with the sump flooding quickly (but me never being able to catch it, since there's a ten or fifteen second window).

 

[svreef]

Does the pump have overheat protection?

 

[IOnceWasLegend]

Does the pump have overheat protection?

Not to my knowledge.

 

[Vhuang168]

How long of a time frame are we talking about? Is it happening over a few days, or a week or longer?

 

[IOnceWasLegend]

How long of a time frame are we talking about? Is it happening over a few days, or a week or longer?

Shortest was a couple days; longest was about ten to twelve days.

 

[Coral reefer]

So if you lose power the sump floods?

 

[IOnceWasLegend]

So if you lose power the sump floods?

Sump doesn't overflow, but enough water comes in to trigger the float switch on my ato, even when I have maximum distance between optical sensor and float switch.

 

[Coral reefer]

Sump doesn't overflow, but enough water comes in to trigger the float switch on my ato, even when I have maximum distance between optical sensor and float switch.

Oh like the tunze high level alarm?
So what about this, level builds in display until a siphon happens and sucks a bunch back down to sump?

 

[IOnceWasLegend]

Oh like the tunze high level alarm?
So what about this, level builds in display until a siphon happens and sucks a bunch back down to sump?

Possible, but I have a siphon hole drilled at the top of the return line to avoid that.

 

[Coral reefer]

Possible, but I have a siphon hole drilled at the top of the return line to avoid that.

I mean your drain(s)

 

[IOnceWasLegend]

I mean your drain(s)

Hm. Possible. How would I be able to avoid it?

 

[Coral reefer]

Hm. Possible. How would I be able to avoid it?

You have two drains? One has a gate?

 

[IOnceWasLegend]

Correct on both counts.

 

[Coral reefer]

Correct on both counts.

So the gate is at full siphon and the other takes just a trickle?

 

[IOnceWasLegend]

So the gate is at full siphon and the other takes just a trickle?

I had it set up like that initially to try and quiet it. Since it's in the garage the water level has typically been about 2" or so from the emergency drain.