Until I get my birdbath wired on Monday, see this latest pump question answered by the pondlady
My tub pump not working (sucking) for pond?
I am using a pump from a jet tub for my pond. I put the intake directly into the water it works normally, I use one stick of PVC with all required fittings and glued properly and the pump will run but not suck.
I can't figure out why the pump will not suck with a 3' stick of PVC attached.
I have primed the pump, done everything I could think of.
There are a couple of things that might be going on. First of all, is the pump running? You can usually tell by a slight hum when you touch it. It could have tripped the GFCI, so the outlet needs to be reset. Try that. Or the impeller could be gummed up with something. Check the intake end of the pump. Use screwdriver to move the impeller to loosen it. Of course, you have the electricity off when you do this.
Or the pump does not have enough head to push the water 3 feet up in the air. That is probably the reason if the pump is working normally otherwise.
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