Sump Pump Clunk After Backup Pump Install

[kevharper]

Had a Zoeller Model 98 sump pump with a Flotec checkvalve. All was good and the pump operated quitely.

This weekend, I added a Basement Watchdog Big Dog battery backup pump to supplement my Zoeller. I wye'd off the 1.5" main line and added two new flapper type checkvalves from Lowes (each one about 12" above the pump). I discarded the old Flotec flapper type checkvalve.

The system seems to work fine. Only difference is that now when the Zoeller cycles off, I hear a mild clunk that I never heard before. Any idea how I might quiet it down?

BTW, there are 1/8" downward angled weep holes just below each of the checkvalves to prevent air lock.

Thanks, Kevin

[hallerb]

probably the check valves.

Honestly if I were you I would run a completely seperate line for the backup pump. In case that single drain line ever fails or a check valve malfunctions where the pump could just cycle water endlessely.

Just get the water out of the immedioate area, like out a wall if it can run away from building.

I am a belt AND suspenders kinda guy.

[Toller]

probably the check valves.

Honestly if I were you I would run a completely seperate line for the backup pump. In case that single drain line ever fails or a check valve malfunctions where the pump could just cycle water endlessely.

Just get the water out of the immedioate area, like out a wall if it can run away from building.

I am a belt AND suspenders kinda guy. _______________

I installed a water powered back up for someone. If it breaks, water will pour into the sump, AND the main sump pump will mainly pump through the broken back up rather than out. Sure isn't what I would want in my basement; I am not sure belt and suspenders are enough there. I wouldn't be concerned except that the pump was so poorly made that failure is quite possible; he bought the pump....

[kevharper]

I'll put the Flotec check valve back in and see what happens then.

Thanks guys...

Kevin

[Jack]

Is there any loose pipe or something that is banging when the the pump shuts off?

[mm]

I have sump pump issues, so I really want to understand this, but I can't follow this paragraph at all. If the water powered backup breaks or if the electric sump pump breaks?

Water will pour into the sump if the water powered back up breaks? Only a certain kind of breaking at most, and wouldn't the water just blow out the designed exit if the valve fails?

The two pumps are connected to each other? The only water powered one I know sucks the water up to the ceiling and blows it out sideways, like a perfume atomizer but using water instead of air, and isn't connected to the original pump at all, except the input tube sits in the same water.

What brand of pump did he buy? I don't want to buy the same thing.