Kettling/banging when system drained

[sha256]

Hi guys

I've had this once before, when I drained my system, once the system was filled and air from the rads removed, and the boiler turned on, it would make banging noises for about 30min-1hr. It also leaked small amounts for about a day.

Now, I'm not GAS registered so I can't open it up, but I will be flushing the system in the next few weeks, and would like to know if there is anything I can do differently this time to avoid the banging/kettling and leaking.

I am running a Worcester Greenstar 24i.

 

[45yearsagasman]

So you're draining a boiler and wondering why it makes noises when you operate it empty. Your boiler can only operate correctly when it is filled and vented correctly. You could seriously damage your boiler if you don't know what you're doing.

 

[sha256]

Did you read the post? I filled the system up, and bled all the air out of the rads, so it probably had some air in it, but by no means was the system running empty. I don't even think the boiler would start if the pressure was zero.

 

[Gas2Air]

Did you read the post? I filled the system up, and bled all the air out of the rads, so it probably had some air in it, but by no means was the system running empty. I don't even think the boiler would start if the pressure was zero.

Flushing it how? The system will need to be drained, unless you have a flush machine. Filling the system up and bleeding the radiators does not give any system a way to rid all the air still bubbling up within an hour. Harder if it's sealed. And don't mouth off if somebody more experienced as you has read a post wrong.

 

[Hugh Jaleak]

I have also read the post and totally agree with what Pete has said. Boiler banging is due to air in the system, doesn't matter how well you try and vent all the air out, some will still remain, and take a while to work its way out, or into a point where it can be removed by venting.

Once the system has settled do you have to top the pressure up again? Point still remains, if you don't understand how the system works, you'll struggle to flush it correctly, and also may damage your boiler.

 

[45yearsagasman]

Did you read the post?

Yes, I did read it, being the first responder should have told you that. Trouble is the way you constructed your post made it difficult for me to understand you correctly. You must ensure that your system, including the boiler, is fully pressurised and vented of ALL air. When you ask for help be a bit more precise and not so rude or you will get ignored. No one on here gets any remuneration for the helpful advice given to diyers and give of there time free of charge. Good luck with your boiler.

 

[gigz]

This should be a doddle to refill/vent unless there's a system design flaw. You could try turning the gas off at the meter and resetting the boiler a few times to stop it overheating and banging.