Sump pump won't run under battery power

[RustyNail]

I'm trying to test my sump pump's battery backup before Hurricane Sandy hits. I killed the breaker for the pump and filled up the sump pit with water. The pump didn't kick on. When I pressed the "pump test" button on the battery box it sounded like a motor kicked on, but no water pumped out. The battery box also has an alarm light which lit up after I pressed the test button.

After flipping the breaker back on, the pump kicked on and emptied the pit, so I know the pump works. I presumed that the battery was dead and took it to Autozone where I had bought it. They tested it and said it had 13 volts so I just took it back home and tested it again with negative results.

I found something on the web that said "use a deep cycle battery, not just a marine battery....there is a difference." That was news to me and sure enough the battery I have is a "dual purpose marine battery."

Could this be the reason it's not kicking on? Any help is much appreciated.

 

[stevemachine]

The deep cycles are the best for sure so then no matter what it should charge up after a total discharge. I don't know if that's a reason as to why its not pumping water. Post some pics of the setup if possible. I know you need some check valves in order for the pump to pump water up the discharge.

 

[IFIXH20]

The Battery backup has a separate pump -- Meaning you have a main pump and a backup pump. The backup pump may be bad or it could be air lock , a air lock pump will come on but will not pump the water out -- Loosen the hose clamp on backup pump check valve , then try backup pump again.

 

[RustyNail]

Thanks for the replies stevemachine and IFIXH2O. I hadn't opened the cover to the pit before, and assumed that there was only one pump that the battery provided power to in the event of AC power failure.

But even if I had opened it up, I likely wouldn't have known that the black horn shaped thing seen in the attached picture was the backup pump. Thank you IFIX for educating me on that.

You probably can't tell from the picture, but the backup pump is pretty close to the top of the pit. Like I said, I didn't open the cover but I'm fairly certain I didn't fill the pit up that high when I tried to test the battery backup, which explains why it didn't kick in on its own or pump out any water when I pressed the "pump test" button.

As it stands, I'm going to monitor the pit if the power goes out to see if it kicks in and will have buckets at the ready in case it doesn't.

Much thanks to both of you, and keep an eye out for my next thread to be titled "I want to move my basement bathroom rough in"

~RustyNail

 

[IFIXH20]

Yes, the black horn shape thing is your backup pump. I would fill the pit to test the backup before power goes out, you will be surprised of the amount of water you can get when the pump is down/not working, so please test before hand. Hope Sandy be a good little girl for you. GOOD LUCK.

 

[actionjw253]

Take out battery job and replace with hydro powered back up pump