Loud Banging, Help Need Please

[Paranoia UK]

Hi, im looking for a bit of advice please.

My Central Heating keeps making a loud banging noise. This happens randomly but quite often, sometimes as much as two or three times a minute. The banging occurs in the Boiler (Baxi 80e - gas). It starts with a faint sound of water or air rushing and then a loud metallic bang. Im tempted to say that it is air rushing into the Pump resulting in the bang.

I cant seem to get any more air out of the system. I have Bled and Bled but it would seem there is no more air. Ive run the heating constantly for a week and still not gotten any more air out. I have also tried draining down a back filling the system (pressurised) too.

Any advice would be much appreciated

Here is some extra info about the situation, it may nor may not be useful:

- The boiler is a Baxi 80e gas combi bloiler.
- I have recently had to remove and clean/descale the primary and secondary heat exchangers
- The PRV and TRV are brand new
- In the last month the system has had cleaner in for two weeks and then descaler/noise reducer for one week
- The system appears to be pretty clean. Ive drained down three times in recent weeks and the water has been very clean, since I used the cleaner in it any way. Prior to this there was a big issue with sludge which I hope to now have rectified.
- I live in a hard water area

 

[Derek Hardman]

Still sounds like a circulation issue to me

 

[Richie_77]

Pump over I'm afraid it's what will have caused the sludge in the first place. You need to re plumber the cold feed and vent on the suction side of the pump no more than 150mm apart. Or even better seal the system

 

[stani]

Pump over I'm afraid it's what will have caused the sludge in the first place. You need to re plumber the cold feed and vent on the suction side of the pump no more than 150mm apart. Or even better seal the system

Isn't a Baxi 80 e a combi?

 

[TBServices]

Tbh the is not a DIY fix, nor is it diagnosable on a forum. You need a plumber to sort the problem, but also diagnose the root cause.

 

[Richie_77]

ahhhh the importance of reading the thread properly yes the 80e is a combi fail.......
Be a flow issue sludge baked on in the boiler heat exchager foulded ports from and to the pump or weak pump.
Ether way your going to need help..

 

[Paranoia UK]

ahhhh the importance of reading the thread properly yes the 80e is a combi fail.......
Be a flow issue sludge baked on in the boiler heat exchager foulded ports from and to the pump or weak pump.
Ether way your going to need help..

Thanks for the reply. I have already taken out both heat exchangers and cleaned, descaled and re cleaned them both. It has made a difference to the overall running of the boiler. Im pretty sure the pump is ok, it runs nice and quietly, the rads all heat up nice a quick and it spins easily when the cap is off. Im guessing I need to take a look at the ports. Maybe Ill borrow the powerflush from work and give it a whirl. Im actually a plumber myself im just not very experienced yet, especially with fault finding. Ive only been doing it a few years. Thanks guys

 

[Dotty]

Are you gsr????????

 

[kay-jay]

Are you gsr????????

Don't worry cropps I've sorted out a simple six
http://www.earplugsonline.com/
🙂🙂🙂

 

[Paranoia UK]

Are you gsr????????

Yes I am

 

[kay-jay]

Good for you chicken. Pm your details to gasman for verification or refer to the above link...

 

[Dotty]

Ok, bit concerned about you removing and cleaning hex's.

Can you increase your post count to 10+ then send a private message to either Gas man or Redsaw who will then check you and then give you access to the gsr private forum.

 

[Paranoia UK]

Good for you chicken. Pm your details to gasman for verification or refer to the above link...

whos gasman?

edit, just seen croppies reply. sure thing

 

[AWheating]

not really sensible to give advise until we are sure of gas safe status tbh. once its sorted the post can be moved to the private forum.