Central Heating Bolier Noisy

[Anastasia]

I have been having problems with my central heating bolier for some time now. To cut a long story short, the problem occurs after about 10 minutes from when the boiler first fires up. An audible click from the boiler is followed by the sound of water rushing through the pipes from the boiler. A loud banging occurs from within the pipes and eventually the system settles down and runs perfectly. I have an open to atmosphere system and the pump runs all the time the central heating is on. I have attempted to bleed air from the pipes, radiators, and pump but nothing works. Please help.

 

[Buzzcut]

Hi ppl,

I've sort of got the same problem... the boiler is pretty noisy, it almost sounds like a kettle boiling. Every 2 mins or so there's a rushing noise and the pipe in the expansion tank gurgles once or twice. The radiators closest to the boiler also need bleeding about every 2 days.

I think that deposits in the boiler are boiling the water and putting air into the system. Anyone agree? The system is pretty old (15 years +) and I think i need to drain it down and Fernox it.

Advice?

Thanks..Buzz

 

[Anastasia]

Thanks for the reply. You may be right about the bolier needing de-sludging, but I have already had all the radiators off and flushed them out thoroughly. Also I have added Fernox to the system. Still the problem persists. It seems to me that when the boiler first fires up there is no water circulating around the system through the boiler. Only when I here this click, like a valve opening, does it start to circulate hot water. It is then that the noise starts. After about 10 seconds 'the air pocket' if thatb is what it is, travels through the pump and everything is ok from then on. I think this switch/valve should operate sooner so that the 'gassing' does not occur. Basically these are all theories and I really don't have a clue. Have you managed to fix your problem, and if so how?

 

[zooankski]

i also have this exact problem and would love to know how to stop it

 

[wilhelm]

oil or gas?

with oil burners,kettling can be reduced with bit of target board. as for gas...pah who cares...

mark z, the last bangin' boiler i went to , it twas blocked cold feed, specifically , the source of a rich vein of magnetite was in this sucker

 

[Nutbrowndog]

Try looking in your loft at the cold feed and expansion tank (the small black one) Has it got any water in it?
If Yes then find where water enters into system (in airing cupboard probably) make sure it is not blocked.... ie any valves on the line that have accidentally been turned off!! or have jammed shut when last opened.
If its an internal blockage you will need to call a heating engineer to replace the pipework

 

[Tillybaby]

Hi,

My cental heating is driving me to distraction with the banging noises, it's a brand new system too,

The bang is always from the same area and is going worse, I did tell the plumber about it and his reply was that it was the pipes expanding and contracting but it isn't because it doesn't stop and bangs about every 30 seconds or so and also it's always from exactly the same place in the system, it then echo's throught the house,

Any advice would be much appreciated before I get a hammer and really do damage,

It's a brand new combi condenser boiler btw.

 

[Anastasia]

Thankyou all for your replies, but so far nothing has helped. I have checked the header tank in the attic and it is about 2/3rds full of water. I have checked for obstructions in the pipe fom the tank to the boiler. Again no problems found. I have this hunch that there is a fault within the boiler that allows the water to boil before sending it around the system. I have thrown the towel in and have contacted a gas fitter to check it out. He is coming in the New year so I will let you all know what he finds.

The thing that puzzles me is that when the system has finished going through the banging stage for a minute or so, everything is fine until the next time it is turned on.

 

[RunAwayHorse]

Hi Anastasia....My boiler is doing exactly the same as yours...eg......fires up runs AOK for very short period, then banging begins in the boiler area - though sounds right through the pipes and this lasts for a minute or two. It then goes quiet until it either goes off on reaching set temp or, re fires up............Sound familiar??

I have had a British gas engineer out and he states that it is probably scale on the heat exchanger. Also, as it is a fairly old boiler better I purchase a new one.
Ii have bought some fernox instead and will be trying that first, before shelling out anything up to a couple of thousand pounds on a new boiler!

I will ley you know if the boiler responds. Also let me know the outcome from yor visiting engineer in the New Year..Good Luck and a very happy new year to you .....Pete

 

[Anastasia]

I will ley you know if the boiler responds. Also let me know the outcome from your visiting engineer in the New Year..Good Luck and a very happy new year to you .....Pete[/quote]

Thanks. I think we should compare notes in the New Year. Do you know if there is a temperature setting on the boiler. If there is I think mine needs turning down. So far I cannot seem to find one.

 

[JohnD]

I have had a British gas engineer out and he states that it is probably scale on the heat exchanger...Ii have bought some fernox instead and will be trying that first...

If it is scale noise, make sure you use a Boiler Noise Reducer chemical, not just an ordinary inhibitor (or both).

 

[RunAwayHorse]

Hi 'A'......most if not all boilers have their own thermostat by which you can adjust the temp' of the water....eg the higher the setting the longer the boiler will fire up for and the longer it allows the water to heat in the system. It works very much as per your room thermostat.

Usually has a range of between 0 and 5........Mine is set on 4 and works very well. keeps the rads & water nice and hot. I adjust the overall temps via the room stat.

I also have radiator thermostats fitted, which allows you to fine tune and adjust the heating to your specific requirements in each room.

This saves the heat being banged out throughout the property unecessarily. Will keep you informed of developments....... You can always e-mail me on [email protected] - Warmest regards.........Peter