How to Wire a Circulator Pump
Circulator pumps are used wherever water or other liquids needs to be forced around or through a series of pipes. The circulator pump contains an electric motor and a one-way valve so the liquid can only travel in one direction. The pump usually connects to the electrical supply via wires that attach to a positive, negative and ground terminal. The connection to a ground source ensures that if something goes wrong, any electrical charge goes direct to ground, shorts the system and blows a fuse. This prevents electric shock.
Remove the screws holding the terminal cover in place using a suitable screwdriver. Notice a round hole in the cover. This is to put the cable through.
Feed the end of the cable that connects to the circulator pump through the hole in the terminal cover. Move it up the cable so it's out of the way. If no cable is already connected to the electrical supply and ready to wire to the pump, use non-metallic 14-2 gauge cable.
Remove about 3 inches of the non-metallic cover from the end of the cable using wire strippers or a knife and long-nosed pliers to expose the three wires inside.
Remove just over a 1/4-inch of the colored plastic from the end of the exposed wires using wire strippers so you can see the copper wire inside. Twist the exposed copper wires using your fingers or a pair of long-nosed pliers to stop the strands from splitting.
Loosen, but do not remove, the three screws on the circulator pump terminals using a suitably sized screwdriver. Use your fingers to pull the metal washers that are under the screwhead toward the screwheads so you can feed the wire under the washer.
Slide the exposed metal wire on the end the green stripped wire under the washer of the ground terminal. Hold the wire in place, and tighten the screw. Ensure the wire is held secure by gently pulling it using your fingers.
Slide the exposed metal wire on the end the negative wire under the washer of the negative terminal. Hold the wire in place, and tighten the screw. Ensure the wire is held secure by gently pulling it.
Slide the exposed metal wire on the end of the positive wire under the washer of the positive terminal. Hold the wire in place, and tighten the screw. Ensure the wire is held secure by gently pulling it.
Slide the cover down the cable and place on the circulator pump. Insert the screws and tighten using a screwdriver. Turn on the electricity if the opposite end of the cable is already wired to the electrical supply or wire a plug to the end of the cable so you can connect the pump to the main's electricity.
- The live terminal inside the circulator pump is labeled "Pos", "Hot" or "+" for positive. The return feed that completes the electrical circuit is labeled "Neg", Neu" or "-" for negative. The third terminal is labeled "Gnd" or "T" and connects directly to ground.
- Non-metallic 14-2 gauge cable is suitable for an electrical current up to 15 amperes.
- The ground wire is covered in stripped two-tone green plastic; the negative wire is covered in gray or white plastic. The color of the positive wire may be red, orange or sometimes black.
- If you have any hesitation about wiring the cirulator pump yourself or are not confident to connect mains electrical wires, do not attempt the task. Get a qualified electrician to wire it for you.
- Ensure your electrical supply is turned off before you commence wiring the circulator pump.
- Wear a pair of very lightweight rubber gloves, in case you come across a live wire.
Stephen Benham has been writing since 1999. His current articles appear on various websites. Benham has worked as an insurance research writer for Axco Services, producing reports in many countries. He has been an underwriting member at Lloyd's of London and a director of three companies. Benham has a diploma in business studies from South Essex College, U.K.
- the circulating pump image by YURY MARYUNIN from Fotolia.com