Boiler goes clonk

[EdT]

Lately our boiler has started thumping - sounds like there's somebody trapped inside trying to get out - quiet loud! Any ideas what this might be, and if it's fixable? (Rather not pay out for a new one)

[Scotfox]

Could simply be air in the system or something like the pump going. More info needed. What type of boiler , Condensing, Combi ?

[EdT]

Old school boiler. Was serviced reasonably recently & given clean bill of health

[GreenDog]

Perhaps there's somebody trapped inside trying to get out.

[eharding]

Could be the pump is on the way out - failing to provide sufficient flow through the boiler, water overheats, much banging and thumping.

[Gad-Westy]

If its a banging noise, its often air in the system. My old school boilers header tank feed was blocked so it was running out of water in the system. A good bash with a hammer and then a bleed of all the radiators cured it. Hopefully your's is something just as simple.

[Gargamel]

Check there is water in the header tank first. In the loft, push the stopcock down on the small tank, does water come through... is there any already in the tank

[E31Shrew]

EdT said:

Lately our boiler has started thumping - sounds like there's somebody trapped inside trying to get out - quiet loud! Any ideas what this might be, and if it's fixable? (Rather not pay out for a new one)

Is it quiet or loud?

[EdT]

eharding said:

Could be the pump is on the way out - failing to provide sufficient flow through the boiler, water overheats, much banging and thumping.

If it helps clarify, it does anywhere between none, and half a dozen clonks before getting going. Thought it was somebody knocking on the kitchen door 1st time!

[EdT]

Gargamel said:

Check there is water in the header tank first. In the loft, push the stopcock down on the small tank, does water come through... is there any already in the tank

Will take a look - ta

[EdT]

btw what on earth is that tank is the loft for? Never understood

[Gad-Westy]

EdT said:

btw what on earth is that tank is the loft for? Never understood

Keeps the system topped up with water.

[Seight_Returns]

I've had this and have cured it by bleeding the radiators.

Not sure how air gets into the system in the first place though ?

[Ferg]

Gad-Westy said:

EdT said:

btw what on earth is that tank is the loft for? Never understood

Keeps the system topped up with water.

Not really.
It allows for the expansion of the heating system water.

[AlexKP]

Ferg said:

Gad-Westy said:

EdT said:

btw what on earth is that tank is the loft for? Never understood

Keeps the system topped up with water.

Not really.
It allows for the expansion of the heating system water.

Or to those of us in the know, "The Header Tank"...

[davido140]

Quick, call 999

http://news.bbc.co.uk/1/hi/england/london/7781379....