Pump bearings' job?

[spurs4ever]

Might sound a strange question but what exactly are the bearings of a circulating pump (ie Grundfos 15-50) for? What's their job? How comes if they go water will pour out of the vent screw when removed??

 

[Nige F]

To hold the impeller and it`s spindle . The water should come out if the screw is removed anyway. The bearings are ceramic and water lubricated

 

[spurs4ever]

if the screw is removed the water should only trickle out though shouldn't it, unless the bearings have gone?

 

[Nige F]

You know I`ve never thought about that Pumps tend to die completely or overheat and die . Is it noisy

 

[spurs4ever]

a bit nosier than normal.

why do they go faulty then, old age?

I have heard about them running dry as the system dries out, maybe due to blocked cold fed over time or system pressure lost beneath pump level.

What's the common way to spot a faulty or failing pump them? Just noise? Cold rads due to no circulation from the pump?

 

[onlyfitidealboilers]

have you a problem with your pump ? or are you just after some technical advice of what to look out for in the field?

 

[Nige F]

Good point

 

[Baxmax]

Are pumps really that expensive.........

 

[lifesagasman]

why do they go faulty then, old age?

old age or perhaps incorrect fitting. instructions with the pump tell you how to orientate the pump on fitting to ensure the bearings have a long life