Central heating pump

[lenny]

Hello,

Can anybody please tell me how to check if a central heating pump is working?

thanks

 

[unguided1]

use a compass if it spins then you know the impellar is turning

 

[kimbo]

Actually the compass will only tell you if there is a magnetic field produced, the impeller could have broken

 

[unguided1]

true but if the impeller has come off there would be little or no heat on the positive side of the pump

 

[kimbo]

You are correct but the compass check should be used as an aid with other pointers to diagnose if the pump is faulty or not.

 

[SimonJohns]

I'm with unguided. All we are looking for is an indication. Not a full strip down to see if all the components are fine.

 

[dontknowitall]

Not heard the compass trick before - you learn something everyday!

I undo the large screw, (using towel) then turn inner screw (3mm screwdriver). If it turns easily then turn on heating and check it vibrates. If it does make sure pipes are same temperature each side of pump.

Not necessarily a better method, but it's the way I do this - until I'm told otherwise by my esteemed colleagues!

 

[kimbo]

The pump of course could be jammed so if you do as dontknowitall says and remove the centre screw and check if the shaft is turning, sometimes they jam with or stick and by turning the shaft with a screwdiver it will kick start it. This sometimes happens with new boilers.

 

[unguided1]

Grundfoss did a promotion where they gave out a keyring with a small compass in it encassed in plastic lost mine a couple of years ago, I wonder if they still do them

 

[fibre washer]

I use my screwdriver by placing on the pump and put to my ear you can hear if it sounds smooth or jammed just like a stethascope