Our central heating stopped working yesterday afternoon with the boiler fault code indicating a boiler overheat.
A quick check showed that the central heating pump wasn't spinning but was getting very hot and making a buzzing sound.
I had to loosen off the pump connections to spin the pump so that i could get access to the central screw and see if the spindle would rotate. Spindle was stuck, but came free and seemed to rotate freely. After a boiler reset the pump seems to work fine and the heating works as it should.
Under normal circumstances i would now be looking to replace the pump (Grunfoss 15-60) i've always thought it was noisy and having stuck once i would assume its only going to stick again.
However, there has always been a slight weep from one of the pump connections and in loosening off the nuts to rotate the pump the slight weep turned into a steady drip. Consequently i took the pump off to find that the gasket on that connection was pretty much missing on one side.
With a new gasket fitted the leaks are now cured but not only that, the pump runs much more quietly than it did before. When the pump kicked in there used to be quite a bit of flow noise which got a lot worse when the system went into bypass. This has now pretty much gone to the point that i assumed that the pump had stuck again as i didn't hear the heating come on in the night.
I've tentatively concluded that there must have been some gasket material either fouling the flow through the pump or stuck in the pump impeller that caused the noise and ultimately caused the pump to stick. Now that this has been cleared the pump should be ok and doesn't need replacing.
Would that be a fair conclusion or should i just bite the bullet and fit a new pump?
A quick check showed that the central heating pump wasn't spinning but was getting very hot and making a buzzing sound.
I had to loosen off the pump connections to spin the pump so that i could get access to the central screw and see if the spindle would rotate. Spindle was stuck, but came free and seemed to rotate freely. After a boiler reset the pump seems to work fine and the heating works as it should.
Under normal circumstances i would now be looking to replace the pump (Grunfoss 15-60) i've always thought it was noisy and having stuck once i would assume its only going to stick again.
However, there has always been a slight weep from one of the pump connections and in loosening off the nuts to rotate the pump the slight weep turned into a steady drip. Consequently i took the pump off to find that the gasket on that connection was pretty much missing on one side.
With a new gasket fitted the leaks are now cured but not only that, the pump runs much more quietly than it did before. When the pump kicked in there used to be quite a bit of flow noise which got a lot worse when the system went into bypass. This has now pretty much gone to the point that i assumed that the pump had stuck again as i didn't hear the heating come on in the night.
I've tentatively concluded that there must have been some gasket material either fouling the flow through the pump or stuck in the pump impeller that caused the noise and ultimately caused the pump to stick. Now that this has been cleared the pump should be ok and doesn't need replacing.
Would that be a fair conclusion or should i just bite the bullet and fit a new pump?
