Sump pumps are used by homeowners to help keep their basements and other low-lying areas free from water buildup during periods of heavy precipitation. Occasionally, sump pumps may malfunction because of physical obstructions in the pump mechanism itself, which requires a partial disassembly and cleaning. A more common issue, however, is the cracking and abrasion of the power cord where it comes into contact with the pit liner or other support structure. This condition requires a repair be made as a proactive measure to avoid future failure of the system. Cord repairs can be made inexpensively, which may negate the need to replace the pump as the result of a total electrical short circuit because of power cord failure.
Things You'll Need
Turn off the power supply that controls the sump pump (circuit box). Remove the three-pronged grounded power cord from the wall socket to ensure safety. Raise the sump pump from its pit so that the full length of the power cord may be examined closely. Wipe the cord down with a clean rag so that it is relatively clean and dry.
Inspect the cord to determine the full extent of the damage and how best to fix it. Run your fingers along the cord to feel for any deep indentations. Check the surrounding areas of the sump pit and/or support structure where the cord was positioned for sharp edges and other protruding items.
Fix minor power cord surface abrasions by wrapping the area 4 inches above and 4 inches below the abrasions with waterproof electrical tape. This will provide some protection and support to the cord.
Fix power cord cuts that have not affected the electrical connection yet by first sealing the cut area with waterproof electrical tape. Make sure the area is completely dry, then wrap the cord tightly with tape 4 inches above and below the cut location. Wrap the tape tightly for several more revolutions.
Apply shrink wrap sealing material to the general area, and heat it with a heat gun. The shrink wrap will contract and melt, forming a tight seal against any future water penetration in the area.
Splice the power cord inside a junction box if the cord is completely severed. Using a junction box is required to meet most applicable building codes. In an emergency situation, temporary repairs may be made by using a utility knife, and stripping 1 inch from the heavy insulation that is covering the cut cord. There will be three wires inside, underneath the insulation covering. Strip off the outer layer covering the three wires, exposing them. Repeat with the other cut end of the power cord.
Slide shrink tubing over the end of each of the bare wires on one end of the power cord. Twist the two ends of the exposed wires together, matching them up by color. Make the twists as tight as possible. Slide the shrink tubing over the top of each of the wires and run it down the cord away from where you are working.
Make sure the wire twists are connected according to color. Using the hot soldering iron tip, place it under one of the twisted wire joints and hold it steady. When the wire becomes hot, apply solder to the connection. The solder should melt, thus creating a permanent connection. Remove the soldering iron. Repeat with the remaining two wire connections.
Wrap electrical tape tightly around the soldered wires, keeping the colored wires separated with tape. When all joints have been covered with electrical tape, push the shrink tubing over the top of the cut area. One piece of shrink wrapping per connection. Use a heat gun to shrink the tubing, so that it melts onto the cord. Wrap the entire area with waterproof electrical tape as an added precaution.
Plug in the power cord, and return the power supply to the "On" position. The sump pump is now ready to use.
In some jurisdictions in the United States, splicing electrical wire outside a junction, switch or outlet box does not meet building code; this, however, does not preclude non-splice repairs made to the cord itself.
Make sure the cord is unplugged from the power source before repairing any components. Make sure the sump pump is plugged in, and has an active power source prior to receiving any heavy precipitation.