I am attempting to make a small pump work as my sump pump. This pump will burn up if it does not have a constant supply of water. I thought I had the system water tight with a check valve on the bottom of the suction pipe. But somehow the water escaped and when the pump turned on, it blew out the 15A fuse in my home fuse box.

Before I try this again, I would like to protect the circuit at a lower amp level. The power strips that I have around here will handle 15A so there would be no gain if I plugged the pump into one of these strips. Do they make 6 amp power strips? If I put in a GFI outlet, would it blow faster than the house fuse? Any ideas to protect this pump at about 6 amps would be appreciated.

Why not put a float switch to prevent the pump from running when there is no water

The suction pipe is ALWAYS under water. The pump has a switch that turns it off when the level gets to a fixed point in the sump.

BUT if you cannot stop the water it will run out of the pipe and back into the sump as soon as the pump stops. So the next time you fire up, you are dry. This pump comes with huge caution stickers explaining that the unit must have an inexhaustible water supply and when it STARTS it better be under water. That is why I put the one way valve at the bottom of the suction pipe. Once I prime the assembly, the pump will lower the level in the sump as required and keep the whole system wet. The problem has been that the pipe connections cannot be made water tight so water slowly leaks out. I thought that I had the leaks fixed this time and it is possible that the one way failed which would drain the system in a heartbeat. I am installing another pump next week and if it happens again, I will be sure to check the water level in the suction pipe before I tear everything apart. If the pipe has water all the way up to the first elbow, then I have once again failed to get a water tight connection. But if there is no water at all in the pipe, it has to be a check valve failure. Perhaps a piece of ka ka got sucked into the valve and held it open but I was not careful enough in the disassembly to do a good autopsy.

Can you build a trap into the piping to keep the pump in the water? if the pump is at the bottom of the trap, it would stay wet even in the backwash when the check valve fails to hold the water. if you could use some large clear tubing (available in big box home centers) you could adjust the size of the trap until the right combination is found. all of this, of course, depends on the location of your pump.

I am not sure that a trap would hold water. I am going to test this with the garden hose out in the back yard today. My concern is that if I plumbed the pump into the bottom of a “J”, the water might siphon out anyway. I THINK that the reason a trap works on your drains is that the pipe is not full of water. With a full pipe, I fear that I will just set up a siphon. I was surprised to find that with a 9 foot column of water, the book says the check valve will be looking at 45 psi. That pressure goes down as you get closer to the outside exit but it is still about 30 psi at the pump. That is why I was having trouble getting the thing leak free.

When I reinstall this thing, I will unplug the pump unless I am in the basement. Then I should be right there for the next failure.