Sump pump makes loud noise

Old 01-19-05, 01:05 PM
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Sump pump makes loud noise

the other day I got a plumber to come in and replace my zoeller sump pump with another one exactly like it. The float switch was stuck and it was all crusted over. It never shut off and I finally couldn't take it. After he replaced it with the new one I noticed it makes a loud thump when it shuts off. Is this normal? I called him back but he said its normal, I find that hard to believe. I can hear the thump upstairs in any room and I just wonder if everyone lives like this. Don't they have pumps that shut off quietly. Or is it just the zoeller pump...cause I'll just get rid of it if it is? Constant loud knocking noises like that drive me crazy and it doesn't make it any better that it comes on every 5 seconds. Is there anything I can do?
Old 01-19-05, 01:21 PM
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Welcome to the DIY Forums.
Usually sump pumps just coast to a stop. I have never heard one shut off. I am assuming the old one did not do this. Are you sure it's the pump and not the check valve thumping?
At any rate, if it is the pump, I would get a hold of Zoeller and voice your concerns. I put their webpage link below. Good luck.
Old 01-19-05, 04:45 PM
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If I may chime in here, The thump you hear would have to be the check valve. As the pump stops, the sudden reversal of the water flow "slams" the check valve shut. Could be that there was a different type valve with the old pump. Another thought that comes to mind is, if the check valve was moved further up the pipe than it originally was, the check will slam harder. Hope this helps.
Old 01-19-05, 05:21 PM
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Make sure that the piping is secure, too.
You're probably hearing the checkvalve slam shut, (as was alluded to in the other posts), but if the piping is loose, it will make the noise even worse.
Old 01-19-05, 10:06 PM
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Hi Yarsix,
-I've worked with lots of kinds of check valves and I have yet to see one that makes a thump loud enough to hear in even the next room, let alone upstairs ! - Wait to hear from Zoeller, or from one of our Mods (DUNBAR PLUMBER)who apparently installs Zoeller all the time.

Do it Right - Do it once.
Old 01-22-05, 08:04 PM
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thanks for all your advice. I guess I do need to take a look at the check valve and possibly give ole Zoeller a call. Appreciate the advice. This is a great forum!

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