How to Detect Problems in a Faulty Circulator Pump

Galvanized pipes
  • 1-2 hours
  • Intermediate
  • 0-50
What You'll Need
Basic Hand Tools

A circulator pump is a device that is used to circulate water, or coolant, through the piping that leads to radiators, air conditioning units, baseboards, or other convection type items. They help to distribute the coolant, or the heated water, through the home in order to regulate the temperature. Detecting problems with a faulty circulator pump is not a difficult project, but does require some time and attention to the symptoms.

Step 1 - Inspect the Circulator Pump

Many times when we believe that there is a problem with the circulator pump it may be something else. Inspect the pump for any signs of obvious problems. This could be in the form of leaks or broken pipes.

Step 2 - Check Radiators and Tubing

One way to detect a problem with the circulator pump is to check the radiators and tubing coming from the pump itself. As the thermostat tells the pump to circulate the heated, or cooled air, check the tubes to see if they warm up or cool down. Touch the radiator tubes to check if they are getting hotter. If not, this may mean that the circulator pump is not working as it should.

Step 3 - Check for Air Bound System

boiler system

There are times when some areas of the home are getting hot, but other rooms are still cold. When this happens it is an indication that the pump is working, but that the lines are air bound. In order to fix this problem you will need to turn off the boiler and drain it. Then release the pressure in the lines in order to get rid of the air pockets. Once the boiler is reset, you should notice that the circulator pump is now directing heated water through all lines.

Step 4 - Fix Any Leaks

A circulator pump is susceptible to leaks at the mounting flanges. After several years of use, the mounting screws corrode enough where they loosen or break altogether. The fix is simple enough. You simply remove the old mounting hardware. Place in a new gasket, and secure the flange with new mounting hardware.

Step 5 - Check Motor and Circulation

A less common problem than leaks or air in the pipes is that of the pump not circulating the water but the motor is running. When this happens you will need to take off the pump to make sure that the wires are not corroded, or the inlet valves blocked.

Step 6 - Check For Problems Causing Noise

Sometimes the circulator pump makes a lot of noise. When this is the case, there are several things which can be wrong with it. Air could be in the lines, but a more common problem causing noise is that a bearing that is going bad within the pump itself. Another reason for the noise is that the pump has been mounted a little askew and is not aligned with the pipes. When there is a bank of multiple circulator pumps, the noise could come from the check valve in one of the different mounts. In order to locate the specific problem, the pump will need to be removed and inspected.