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How to Replace a Broken Sump Pump

By Our Home from Scratch on Dec 03, 2012

Hey everybody!  Sorry if I’ve been AWOL lately.  Work has been pretty crazy and I’ve been unable to read or comment on my regular blog reads.  I’m hoping to set aside some time in the next day or two to get caught up.  In the meantime, I’ve also been busy with annoying, but necessary repairs around the house.  This past week I had to replace our sump pump.  As far as technically challenging repairs go… on a scale of 1 to 10, this one is around a 3 or a 4, where changing a light bulb would be a 1 and replacing a furnace is a 10.

So, we’ve lived in our current NJ house for a little over 2 years now and we’ve never, ever heard our sump pump run.  Even during and immediately after hurricane Sandy it was quiet.  About a week ago, Lisa had been noticing this recurring humming noise coming from the basement.  In typical, ‘you’re probably hearing things mode’ I blew it off as just typical furnace noise.  Then a couple days later I was in the basement grabbing some tools and I heard it first hand.  Crap.  The sump pump was running for 30-45 seconds, would stop for 30-45 seconds then would run again.  It wasn’t raining, and it hadn’t rained heavily for a couple weeks.  Something is wrong with this picture.

If you don’t have a sump pump or are not sure how it works, I can explain.  Most new home foundations and a lot of existing homes are outfitted with a perforated plastic pipe that wraps around the outside perimeter near the footer or the base of the basement wall.  It then gets covered in gravel to prevent sand and dirt from clogging its slits.  This pipe, which can be sometimes referred to as a “weeping tile” (ala Mike Holmes) then runs into the basement into a large bucket.  The bucket is equipped with a sump pump that evacuates the water back outside, except it does so away from the house, keeping the foundation dry and less likely to settle further or become disturbed from water erosion.

Here’s what our bucket and evacuation pipe looks like…

sump pump (2) The small pipe on the left is the condensate discharge from the central air system.  The larger pipe on the right is the outlet pipe from the sump pump.  These systems are also vented and may have two large pipes as opposed to one.  We DO have a vent in this system it’s just hidden in the basin.

That large plastic box is a check valve.

sump pump pvc check valve The check valve prevents the water that was just pumped out from coming back down the pipe and back into the sump bucket.  It’s just a little rubber gasket that only opens in one direction.  When this pump was continuously running, the first thing I assumed was the check valve wasn’t sealing and it was constantly sending the water back into the basin only to be ejected again.  After taking the check valve apart, cleaning it, putting it back together and then plugging the pump back in, it was still running constantly.

Time to investigate further.  So, I disconnected the check valve, slid the AC discharge pipe out of the way and popped off the cover to the basin.  Couple things I noticed:  1.  there wasn’t much water in the bucket, only a couple of inches.  2.  there was a spider in there with a leg span about as long as my thumb and with WAY more hair on its legs than mine.  I’m generally not afraid of spiders.  I was afraid of THIS spider.

Sump pumps usually have some type of float mechanism so when the bucket fills high enough with water, it will switch on.  This pump was running AND the float was a couple inches above the water.  This thing is straight up broken.  Now I could try to repair the switch mechanism or I could just go out and buy a new one, a new shiny one that didn’t have giant banana spiders hidden inside.  I think you can guess which way I went on this.

old sump pump new sump pump They even sell these in stainless steel!  As if it were going to be on our kitchen counter next to the toaster.

The replacement went pretty easy.  I disconnected the old sump pump at the check valve union and just pulled it out of the sump bucket.  Easy.  The new sump pump and the old sump pump have different PVC fittings.  Take note, the one on the right has a fitting that goes OVER the threads.  The new one is a female type connection, where the PVC will need to go INTO the pump.  So much for reusing that pipe.

Here’s a closer shot of the fittings…

in vs out So, after assembling a few pieces to the new pump, I glued on the male fitting to a small section of 1 1/2″ PVC pipe.  Lowes and Home Depot sell certain diameter pipes in larger 8′-10′ lengths and a few at 4′-5′ lengths.  Since this is a smaller section, I opted for the car friendly 5′ piece.

To glue on the male fitting (which I fitted up to the display pump at Lowes to make sure I had the right one), I just placed my pipe on a stable surface to start.  You’ll need both the purple primer and the PVC glue for this part.

pvc glue and primer I applied the purple primer to both pieces and then the glue to both.  You need to put these two piece together within a few seconds once you apply the glue or it will harden prematurely.

pvc primer To glue them together, place the male fitting over the pipe, hold it steady for a few seconds, then try to give it a very slight turn.  If you get resistance to the turn, you’re good.  I like to hold the piece onto the pipe for maybe 30 seconds to a minute before letting go.

pvc glue Okay.  The new pump was then connected to the pump and placed into the basin.  I marked both the new pipe and the old pipe for length taking into consideration a gap for the new check valve.

To cut the new pipe to length, I just used my miter saw.

cutting pvc With the new pipe cut, I added some thread compound to the male fitting and reinstalled the pipe to the new sump pump.

thread compound To cut the existing part of the discharge pipe that was hanging from the basement wall, I used a hack saw.  You could also use a reciprocating saw, aka a Sawzall, but I find they shake the pipe too much.

The new check valve is a flexible rubber boot style and it slides over the pipes and gets clamped down.  You just need to leave some extra room between these pipes for this valve.

sump pump check valve Sorry that photo is a little blurry, but you get the idea.

After the new valve was installed, I plugged it in and tested it by lifting up the float.  Success!

new sump pump

The flexible check valve let’s you get away with the pipe being slightly misaligned, which is nice.

So, that sucked.  Any annoying repairs in your future?  Any 8 legged monsters?

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