Either the start cap, start switch or possibly not getting enough voltage. You need to check winding resistance to ground. The manufacturer should have instructions on this. If there is any reading below about 10meg, just replace the pump. If it ran dry it will have burned up the pump internals. This pump is not rebuildable. I tried once. So many parts and they make them so expensive you can buy a new one. There are other pumps that cost much less on the market. Walrus makes one that works well and you can get two for the price of one Grundfos. I would avoid the ones that have a pressure tank and other stuff. They work, but take up a lot of space and have too many things to fail. You can replace the simpler pump only models for the price of repairing the them.
Answers & Comments
Either the start cap, start switch or possibly not getting enough voltage. You need to check winding resistance to ground. The manufacturer should have instructions on this. If there is any reading below about 10meg, just replace the pump. If it ran dry it will have burned up the pump internals.
This pump is not rebuildable. I tried once. So many parts and they make them so expensive you can buy a new one.
There are other pumps that cost much less on the market. Walrus makes one that works well and you can get two for the price of one Grundfos.
I would avoid the ones that have a pressure tank and other stuff. They work, but take up a lot of space and have too many things to fail. You can replace the simpler pump only models for the price of repairing the them.