Noisy boiler flue during heavy rain.

[DB_SamX]

I have a combi boiler flue which is a round 8 years old and serviced annually. THe flue runs horizontally (I believe) over the wardrobe in my bedroom, to an outlet in my external wall.

Occasionally there is a ticking/dripping noise seemingly coming from the flue (not the boiler I think). This has been happening for years but never bothered me.

The last couple of months, when we have had storms, that ticking/dripping noise makes an absolute racket (2/3 ticks/drops a second, continuously), and typically in the middle of the night, it wakes me up.

Reading online, it seems a common occurrence due to rain getting in the flue, but I am really struggling to understand how the noise is created. I even asked the chap who came to service the boiler a couple of weeks ago, and he was vague, and said not much can be done. But I think he had no interest in helping me beyond servicing my boiler.

Can anyone shed some light on what's happening, and if there is a solution? I need to get a gas safe certificate by December due to being in a block of flats, so need to get an engineer in for a visit anyway. I'd prefer to be a bit more knowledegable before I call them to arrange the visit.

 

[Sui]

Pretty sure it's just the rain hitting the top of the flue and the noise carrying along the pipe to the inside? I've just had a new boiler installed in the flat I'm renting and the flue is a lot chunkier, needless to say when it rains it makes the same noises you experience and it's only about 6 feet from my head which causes me to wake up

 

[lewism]

It's just an echo from the water hitting off it. A flue is just a big empty cylinder so the noise gets amplified. You can get high level adaptors and various other accessories that may be of help. What to watch out for is the age and make of your boiler as it could be cost prohibitive. Also in a block of flats unless you're on the ground floor they are also usually a pig to do. You may be cheaper boxing in the flue with the appropriate vents. However, i'm not gas safe so I would take it as advice rather than gospel.

 

[DB_SamX]

Ah, good thinking about the echo. I am on the ground floor so retrofitting a cover of sorts to the outside wall may be an option. I'll look into the regs and get something done professionally if needed.

 

[BigBoy]

Ah, good thinking about the echo. I am on the ground floor so retrofitting a cover of sorts to the outside wall may be an option. I'll look into the regs and get something done professionally if needed.

Do not install anything within 300mm of the flue especially an over hang, by all mean install a rain deflector my it MUST be over 300mm above the flue and even then it might not stop the sound.

 

[DB_SamX]

I went to inspectbthe flue yesterday and turns out the noise is actually from the condensate pipe which is closer to to the floor outside the flat. Not the flue at ceiling level after all.

Anyone know how a condensate pipe is routed? Does it start high (my boiler is at torso-head level) and then drop low in the cavity wall or something?

Not sure what causes the noise now that I know it's the condensate pipe...itsbonly been light rain since yesterday so not had any noise.

 

[BigBoy]

It should be a vertical drop from the boiler then 45°angle after that into a drain. All plastic pipe or the condensate will rot the copper/steel.