noisy pump

[ivanov]

Hi,

After I added Fernox Leak Sealer to my sealed CH system and bled the rads and pump multiple times, every time when the pump starts there is a "water running like" noise coming from the pump for few seconds and the it disappears. Any idea how to get rid of it?

PS The pressure is set to 1.4 bars but it goes to 1.8 when the water is hot.

Thanks

 

[felix]

That noise is probably air in the pump. It sloshes about for a bit before being swept out and away. I know you say you've bled the system many times but you've also put new water in it. Tap water has disolved air in it which comes out of solution as the water heats up. It could be getting trapped in odd places around the system. I know from experience that it can take many weeks of bleeding before such air pockets are eliminated.

 

[ivanov]

Felix that for the advice. Unfortunately I've been bleeding many times but no air comes out of the radiator but it still make noises. Is possible that air is locked at the opposite end of the bleed valve and it cant come out because it is quite wide radiator (~130cm)?