another combi boiler pressure problem

[Zarniwoop]

My combi's heating water pressure is low when the heating comes on.
So it mkes alot of noise as it heats up.
I assume this is because the water can boil in the pipes at the low pressure.
When it heats up it fine and the pressure builds up to the rated pressure, this may because there is air in the pipes.

I have bleed the rads and re-pressurized the system this helped for a while. But now I'm back to square one.

I have now run out of Ideas.

Help !

 

[Mahala]

This sounds familiar. I have just had a new boiler installed and am experiencing similar issues.

According to the installer, the system should settle down after some time (not specified!). Water contains dissolved oxygen which ends up in the system and rattles around, but there should be a vent built into the boiler to allow it to escape.

Not much help I know but at least you know you are not the only one with combi problems.

 

[Zarniwoop]

Thanks

I will keep on bleeding the system then.

 

[bristol01]

I have also been experiencing the same problems (my make is SIME). However I had mine installed march 2002 and can still hear sounds.

My pressure also fluctuates when switched on and off.

regards

 

[breezer]

i am not a plumber or heating engineer, but if you are refiling the system that would indicate a leek, check all the radiator pipes and see if any are damp, i would guess its only a slight drip yo are looking for