When testing my battery powered backup sump pump a few weeks ago, I
noticed it wasn't pumping any water (it was making noise like it was
trying to). I disconnected and then re-connected the pipe and it
seemed to start working again. Now a few weeks later, I checked it
and had the same problem, and again it was resolved by disconnecting
and re-connecting the pipe.
The battery is only a couple years old and the water levels look fine.
Any idea what could be going on?
On Sat, 3 Jan 2009 12:40:47 -0800 (PST), firstname.lastname@example.org
I think the problem is your lack of a vent hole, but if you want to
check the voltage on a 12 volt battery, connect a car lightbulb across
the ternmainal and see if it glows at the proper brightness. Better
yet, connect a car horn and see if has the proper noise. (Although a
horn in a cement basement might be a bad idea.)
I wrote my whole post below and then realized the key was here. I'm
not talking about the battery's total condition. If his multimeter
were working (and it's not) the meter wouldn't give the full battery
condition either. I only gave him a substitute for a voltmeter and
I'm only talking about the voltage, and the voltage is a good
indicator of whether the charger is functioning. Hey, I just looked
to see how the topic came up, and you were the one who asked what is
the voltage in the first place. You didn't ask about battery
condition in this subthread.
I think those are two alsmost separate things. If the bulb or horn
doesn't work it might be because the battery is worthless or because
it is discharged.
OTOH, if it's sulfated and worthless it won't light the bulb or blow
the horn. If the battery is still good but discharged, the horn will
make less than the expected amount of noise, from nothing to a click,
to a buzz, to a weak horn sound, depending on how undercharged it is.
It takes a pretty high voltage to give a full blast sound.
The horn is better than the lightbulb because when the bulb is almost
bright enough or more, it's harder to judge just how bright the bulb
is than to judge the sound of the horn. And because the horn draws
more current, which matters when the battery isn't charged enough.
This comes up most often in cars, where people are told to check if
their battery is charged by turning the lights on. Especially in the
day time, it's really hard to tell how bright a lightbulb is, and much
easier to tell how loud the horn is.
I"m not saying this will tell you how much longer the battery will
work, but it will tell you what the voltage is when you do it. It
won't give a specific number of volts, but it will still show the
I looked and didn't see any holes. I should also mention there
appears to be two check valves installed in the line.. One right
before the connection to the pump and one at the 90 degree turn in the
pipe toward the wall. Does the hole need to be above the water line?
If so it may not be possible if it has to be below the first check
Apparently some pumps have an anti-airlock hole built-in. If you can,
check your owner's manual to see if yours does and where it's located.
If you don't have that manual available, check around where the main
pump housing fits into the base for a vent/relief hole. If you find one,
be sure it's not plugged up. From what I've read, that's a problem with
the built in anti-airlock vents -- being near the base of the pump,
closer to the bottom of the sump pit, they're more likely to be plugged
with dirt and debris than if they're higher up in the discharge pipe.
But in any case they need to be between the pump discharge and the check
valve, though not necessarily above the water, though, again, if not
above the water they are more prone to clogging up and also more
difficult to check.
My sump pump (Wayne CDU790) does not have a built in anti-airlock vent.
The check valve is on the discharge line above the sump pit and the
anti-airlock hole is about a foot or so below the top of the sump pit so
it sprays onto the sump wall when the pump is running. Even there, it
does get a bit of dirt build up over time so I clean it out yearly with
Here's as good an explanation of the sump pump "air lock" issue as I've
"Envision the sump pump drawing down and sucking air before the pump
switch deactivates. Now you have a small pocket of air around the
impeller and nothing leading to the bottom side of the check valve.
The impeller does not have the force to move air, only water. That 3/16"
[anti-airlock vent] guarantees that water will enter into that chamber
where the impeller is so that the pump can force the check valve open.
Doesn't matter where that check valve is; those pumps are not designed
to move air.......only water.
Even if the check valve was 8 feet up.......that air hole will allow
that huge pocket of air to displace quickly enough to engage water to
push up to open the check.
It's not rocket science but I've seen too many pump failures that did
hundreds of thousands of dollars of damage and I can go right to the
pump, take it out of the pit and start it right up like there is nothing
wrong with it.
And there isn't; the pump air-locked and had nothing to do with product,
had everything to do with workmanship error."
On Jan 3, 12:08 pm, email@example.com wrote:
I would not trust those chargers without knowing it keeps a proper
voltage be testing it, I would think a properly charged battery should
last 20 + years. Unless the battery is kept at a minimum of 12.8 it
will sulfate and be ruined in a year. www.batteryuniversity.com has
all sorts of battery info, that could be the real issue a weak
You are kidding, its basicly unused, no discharging just maintenance
charge, no vibration as you get in a car that destroys plates. Low
voltage kills them in a 6 months. He replaced one after 1.5 years,
that simple fact tells me its a charger issue. On solar instalations
you get better life than cars, vibration is a factor you have not
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