Swishing sound from pump

[alanrumble127]

Can anyone help.

I have a central heating system which heats both the rads and water. The radiator side works fine and very quiet. However when I am just heating the water, there is a contined swishing noise and the sound of trickling by the boiler. I have checked that there is no over pumping in the loft tank.

It seems that there is air in the system, but only when the water is on, the radiator side is fine. I have turned the pump down but this makes no difference. I am concerned that the air could damage the new boiler.

 

[bengasman]

Seems like air, one of the problems that always returns with open vented systems.
If the boiler is quite new, get the installer back to sort it.