How to Replace a Circulator Pump

A circulator pump is a special part (usually found in heating and cooling units) that helps to pump gas or liquids (like water or cooling agents) through the pipes and tubes of the system. In fact, you can think of the circulator pump as the heart the heating or a/c system, pumping the liquids that the machine needs to do its job. If the pump malfunctions, then the entire machine will shut down.

Fortunately, however, replacing a circulator pump isn’t quite as tricky as it sounds, and in fact is a job that the fairly experienced do-it-yourself can take on for him or herself. If you’re ready to tackle the job, just follow the handy steps outlined below to bring your heating or a/c unit back to life.

Tools and Materials Needed
  • Circulator pump
  • Pump flanges
  • O-rings
  • Gaskets
  • Pipe cutter
  • Wrenches
  • Pliers
  • Electric pliers
  • Bolts
Step 1 – Find the Right Circulator Pump Replacement

Before you can roll up your shirtsleeves and get to work, you need to make sure that you’re working with the right materials. Take note of the model of circulator pump you’re replacing and make sure to get precisely the same model when you go to the home improvement store. If that model is no longer available, talk to a pro to find out which currently available model is the best replacement.

Step 2 – Cut the Power

Because circulator pumps do draw electricity, for safety’s sake you need to make sure the power is cut before you start working. You may even want to turn off the circuit breaker. Remember to be very careful when doing any type of job that involves electrical wiring; use tools with rubber-insulated grips when possible, wear rubber soled shoes and work in a dry environment. After turning off the power, take the pump’s cover plate off and disconnect any electrical connections.

Step 3 – Drain and Remove the Circulator Pump

Using your wrench, gently loosen the nuts connecting the pump to the pipes. This will trigger drainage of any remaining water or liquids, so make sure to have a bucket or pan handy to catch the overflow. Once all the liquids have emptied, then you’re ready to take the pump out of the machine.

Step 4 – Install the new Circulator Pump

Insert the new circulator pump. You will need to connect the associated pump flanges with O-rings or gaskets, depending on the model of the pump, and secure the pump to the distribution pipes with the bolts and wrench. Make sure all the connections are tightly secured to prevent leakage, but also take care to not exert too much force! Finally, remove the circulator pump plate and connect the electrical wires that you disconnected from the old pump into the new pump housing. Replace the metal plate. Open all valves to allow any trapped air or water to escape, and set the speed setting to the appropriate level (the same level as the old pump), if applicable.