CH & HW Banging - Help!

[Mungo]

I drained my CH system yesterday and fitted a new radiator and towel warmer, where previously there had been one radiator.

I switched the combi-boiler back on using the timer but noticed the pilot had gone out. I relit it okay, but when the boiler fires up fully there is a very loud banging and it shuts down again. This happens for both the HW and the CH. I let it run for a couple of hours and the new radiator heated up but none of the others, plus there is no HW. All radiators have been bled.

I thought it might settle down overnight but was rudely awakened at 4.30 when the timer kicked in and there was this almighty banging. Had to have a luke warm shower this morning and a grumpy missus through my incompetence.

Any ideas to help please?

 

[oilman]

Sounds like the boiler is full of air. Have you bled it?

 

[Mungo]

Ah, boiler bleeding. Didn't know there was such a thing. Is that easy to do or do I need an engineer?

 

[ChrisR]

YOu need a bleed point. Should be one on any bit of pipe which goes up then down, eg in your airing cupd by the HW cylinder. Also bleed the pump by removing centre screw - it dribbles a little.