Hello all,

I have found that the backup sump pump doesn't work as expected. Here is the problem:

When the pump is activated, I can see lots of water ejected from a small hole which is used to prevent air-lock inside the sump pump. However, the flapper inside the Quiet Check Valve doesn't move up AT ALL! I have tried to block the eject hole with finger but the check valve still doesn't move up.

One observation is that after the main pump finishes the cycle and the quiet check valve connected with the backup bump will release a few air bubbles.

Question 1> Do you think that the quiet check valve for backup is broken? Or what other issues may cause this problem?

Question 2> What is the procedure to replace the check valve?

Please see attached images for details. The pump setup is similar as mine and I borrow it from internet.

Thank you

 

New install?
100% sure there installed in the right direction?

 

@joecaption,

This is NOT a new installation and it was installed by a plumbing company in 2008.
As you can see from the image on the second row, the direction of the valve is correctly pointing to UP.

Thank you

 

Did the backup ever work? Assuming it did, it's possible a small piece a debris has jammed the flapper on the backup check valve. You can take out that check valve by unscrewing the threaded caps. You should unscrew the bottoms of both valves first and then put a large bucket underneath one of them. Using a small stick or a screwdriver from the bottom of the valve, push up the flap and let the water in the pipe drain into the bucket. Once all the water is gone, you can unscrew the other end of the valve and inspect or replace.

Another possibility is that the backup sump pump has a problem and can't generate enough pressure to overcome the pressure of the water on top of the check valve.

I'd take out both valves, rinse them out well and make sure the flappers are free, and then reinstall and retest. If the backup works at first when there is no water above the check valve, but then doesn't work when the pipe is full of water, I'd suspect a problem with the backup pump.

Hope this helps.

 

@CarbideTipped,

Thank you so much for your information and I will report back after I receive the new replacement valve.

Best

 

Another thought...when you were observing the backup pump operating, was the main pump also operating? If so, it's likely the backup couldn't overcome the pressure from the main pump. You should only test the backup when the main is off.

 

I'd agree with that statement.

Although it is possible...... I've never seen one of those valves get stuck before.

 

Hello all,

Here is the follow-up on the problem.

I replaced the Quiet Check Valve and now the valve can open a little (5mm) and the backup pump now can discharge the water. Based on my observation, the valve with main pump opens much wider and the main pump discharges the water much faster. I assume this is normal due to the capacity of the backup bump is weaker than the main one.

BTW: the old replaced valve looks fine to me and I will clean it up and use as backup in the future.