cooperplace

any thoughts re the pump?

thanks for the suggestions guys. Here's what it's doing: if I apply power with the shaft vertical and the end inspection port pointing DOWN, it starts and runs fine. The moment I move the pump so the shaft is horizontal, the impeller/shaft assembly is able to move about 1mm up and out of the motor housing and it then locks solid. I can duplicate this behavior by running it with the impeller cover off. It's a mechanical, not an electrical problem. I'm told that the water goes down the drain in the opposite direction in the southern hemisphere.

No, it doesn't sound like that. I have already checked the connections: they are fine.

I bought a new Grundfos 15-50 pump on Ebay for my hot water circulating loop. Plumbed it in, got water in the system, turned it on. Didn't start. Tried all 3 speed settings, wouldn't start. I removed it, and checked that the voltage is getting to the pump. It is. So I took the impeller cover off, and (this is done with the impeller wet) with the cover off, it spins beautifully, and if power is applied (just for a second), it starts and turns perfectly. But when I put the cover on, it binds up and won't turn. All I did was remove the cover. I didn't touch the gasket. Spins without the cover on, won't spin with the cover on. I can't take it back because it came from a private seller on Ebay, bought it months ago. And yes, I'm installing it with the shaft horizontal. Any suggestions would be much appreciated. Peter.