rattling/knocking on rising main

[makitaman]

Can anyone help with a problem with rattling/knocking on our rising main. To give a brief layout - rising main enters house, to main stopcock then onto an 'electrolyte' scale inhibitor, after about 70 cms takes a sweeping 45 degree left turn. The rattling seems to be in the actual scale inhibitor itself.

This problem has started since a lower floor radiator was removed in order to plaster room. The rad was put back and a number of rads needed bleeding but this still hasn't stopped or even reduced the knocking sound.

Hopefully you guys can give some advise - many thanks from frustrated chippy

 

[Nige F]

electrolytic........hocus pocus .......rip it out and replace with a piece of copper pipe

 

[Bamber gaspipe]

If the problem only started after removing the radiator then perhaps the valves were replaced on the wrong ends, especially if you have older Thermostatic radiator valves. If the TRV was replaced on the wrong end (return) you may be experiencing `chattering`at the rad. It`s worth checking.

 

[makitaman]

Thanks for the replies, the trv's were replaced in the correct positions, as for the scale inhibitor - we inherited this system and prior to rad removal all was well. Is there anything else we could do ?

 

[kevplumb]

Thanks for the replies, the trv's were replaced in the correct positions, as for the scale inhibitor - we inherited this system and prior to rad removal all was well. Is there anything else we could do ?

remove it they don't work anyway the magnet will be loose

 

[Bamber gaspipe]

Is it a combi or do you have tanks in the loft? if you have tanks in the loft go up & check the ball cocks in each tank.(one for hot water,one for heating) it may be that after removing the radiator & replacing it the tank is now trying to refill the radiator & you have a faulty ballcock producing water hammer on the rising main.(this fills your tank). Check it out.