Help, loud banging noise coming from boiler.

[mutley racers]

Hi guys, am in need of some help. I have checked all the posts on kettling and am not sure if this is my problem.

A couple of months ago, i replaced a radiator for an old dear who had gone on holiday and found one of her rooms was soaked through. It turned out, that the radiator had a pin hole leak in it. Where it had rusted.

So, i drained the system down, and fitted a new one. Then, trying to fill the open vented system back up was a nightmare. I put my hose onto a drain valve on rad and connected it to the out side tap and put the 3 port valve in manual and proceeded to fill. There were 2 air vents on top of the flow and return pipes. Manual ones, and so i twisted these open and was only able to get water to come out of one of them.

I had left it filling for around 15 minutes and still didnt get any water out of the one aav. But it came out of the f and e.

When i turned the boiler on, she said that the noise it was making wasnt there before. So i just bled the rads and left it running and it disappeared.it Was quiet.

Well today the lady knocked on my door and said that her boiler is making a loud noise.

Is this because it is built up with sludge?

Could i turn the pump upto 3?

Or should i drain down and refill?

Or get the boiler looked at by a gas engineer.

Or maybe even just add a chemical to it

How can i tell if its blocked using a magnet?

How can i tell if the system is not totally filled up with water?

Any help will be much appreciated.

Regards

Mutley

 

[Gray0689]

Why did you drain down to
Change a rad??

 

[SafeGasInstall]

air in system running dry

 

[gaspastemania]

I had a problem like this a couple years ago and it did turn out to be air , filled up flashed up went out the van and the painter working inside shot out saying he thinks boiler is going to blow up ,Went inside and loud banging noise was reverberating from system ,,,,put more pressure in and shut few rads down here and there and seemed to push the air out .

 

[sparky]

Reason you couldnt get water from other manual vent(thumbscrew) was it could have been blocked. A pin in the end of the vent may have cleared it.

 

[SafeGasInstall]

when you re fill it did you not make sure all rads are getting hot and when call for hot water water heats up cylinder ! POOR workmanship if YOU DID NOT !

 

[mutley racers]

Hi guys, thanks for all the info. I had to drain the system down as the valves were all jammed and not shutting off. So i just drained it down. I did run all radiators and to make sure they got heat, also the hot water circuit. And every thing was ok. The noise stopped while i was there after it had ran for a bit.

I think i shall go back there tomorrow and shuff a pin down the other air vent and see if that side is full of water.

Am thinking that as the old radiator had corroded that when i drained it down, maybe some scale has got lodged into the heat exchanger and so limiting the flow of water and causing kettling maybe.

I thought the the mains pressure in the system would have got ridden of any air and dislodged the crud in heat exchanger or pipe work. I think i will go around with a magnet and see if i can find a blockage any where.

 

[mutley racers]

hey sparky, thanks for the advice. I went back there and shuffed a pin in it and it was blocked.

So the system was full.

While i was looking around i thought i would turn up the pump speed. When i looked at the pump, it was only set on 1. I must have done this by mistake when i left it.

So i just turned it upto 2 and all is great.

Naughty me.

Thanks for all your help guys.

Its much appreciated

 

[RoryD]

pinholes generally = sludge; usually there's a blockage where the cold feed enters the system ()neutral point, that'll need cutting out. I backfill thru the vent to 'get by until we can get back to rectify