Rushing of water

[deepseadiver]

Hi all,

Before I continue, please accept my seasonal greetings

I have the old style central heating system with a water tank in the loft, and I have been experiencing rushing of water through the central heating system pipework (At pump). The issue only really occurs when the hot water demand is being selected, and never happens when the central heating is on itself. During the period of water rush, the pump speeds up then gradually slows down as the water rush period passes, this is repeated every so oftain until the hot water demand is turned off from the programmer.


When the hot water demand is turned off, the water rush occurs roughly twice after, but to a lesser extent on each occassion. Im not a plumber or engineer, but it sounds as if there is a build up of pressure and when it gets to a tipping point the water rushes through the pump untill the pressure has equalized.
T
he pump has been slightly noisy, and its speed is currently selected in position 2.

Many thanks for any advice!

 

[diamondgas]

Hi and :welcome: to the forum

The rushing you describe sounds more like air running through the pump. First thing you could do is make sure it's not something like the boiler overheating? Turn the thermostat off on the boiler and see if the noise still occurs .. If its still there then make sure you have enough water in the system; check that there is water in the smaller header tank in the loft.... If thats okay then you'll most likely be drawing air in somehow. That diagnosis will most likely need someone to take a look

 

[deepseadiver]

Hi,

Thank you for replying and I will follow your advice. What is the recommended temp setting for the water tank anyway? How do I tell if there is enough water in the header tank? Should there be a level marked somewhere?


Dont worry, I know my limits and wont do anything daft

 

[wheeto]

What is the recommended temp setting for the water tank anyway?

You should aim for at least 60 degrees C to avoid legionella growth

How do I tell if there is enough water in the header tank?

Pretty much any water in the cistern in the loft, when the system is cold, is enough.

 

[deepseadiver]

Thanks wheeto,

so if its dry we have a problem and if not call for a competent person to investigate the issue further?

Merry xmas.