Circulators
A circulator pump provides the hot water needed to heat a given zone in the home. When it fails, that zone will be without heat until it is remedied. Noisy operation, corroding flange connections, excessive heat on the motor and excessive power draw are all signs that a circulator is on its way out.
Another problem we see quite often is an incorrectly installed circulator. If the motor is not mounted in the proper position, premature failure is virtually guaranteed. Also, if one or more circulators are not installed in the proper place within the near-boiler piping, they can create lower than normal operating pressures during certain parts of the cycle. This causes the pressure reducing valve to open due to a false reading of lower pressure, introducing more water and resulting in higher static pressure once the heating cycle is complete. These higher pressures can cause premature failure of your expansion tank and pressure relief valve.