Ideal Response 120 Combi Loud Rumbling

[abrahamlove]

Hello. Thought there might be someone on here who can diagnose what half a dozen British Gas engineers can't. Our Response 120 has (for the last couple of years) made a very loud rumbling noise from time to time. It usually happens if you switch the hot water tap on in any of the rooms. Now and then it happens when the heating is on. Starts rumbling for no reason (no tap has gone on, no rad valves have been opened or closed). Turing of the tap or turning off the boiler and back on again (advancing the program) fixes it instantly. It will usually happen half a dozen times each day. Sometimes it stops of it's own accord even with hot water running, sometimes you have to turn of the tap. If it starts because of the radiators (no taps on) then it doesn't stop on its own. for your pleasure I put a video on youtube. It stops at the end because the hot tap was switched off. This boiler has been serviced recently. when the boiler rumbles it must also break its seal slightly since CO is produced (enough to make a CO alram in the cupboard flash for a few seconds). the flue has been checked and British Gas said it's fine to use. Any ideas?

http://uk.youtube.com/watch?v=yJ5vdgtBYBU

 

[ChrisR]

Supply pressure too low probably due to undersized gas pipe. May be dodgy meter regulator. Both cause that noise.
May also be a flue fault or case seal leaking, causing the noise, and the
CO alarm shouldn't go off at all that's dangerous. Get it sorted, don't put up with it.

 

[nickso]

what did BG change?

 

[abrahamlove]

Thanks. BG changed so much I couldn't even tell you. I know little to nothing about boilers. They have visited this boiler a dozen times in 5 years or so. It's a bit like Trigger's broom in that I doubt there is very much of the original thing left. they did get a new seal for it - but then I think the BG engineer said it didn't need changing. No idea why. thing is when they ocme round - sod's law it rarely makes the noise - or it does a fgentle rumble for a moment and stops again. I wonder if to get Ideal in instead?

 

[mickyg]

fiver says they've never checked the inlet pressure

 

[abrahamlove]

OK - so maybe I am barking up the wrong tree here, but as you said inlet...underneath the boiler it says 'gas inlet' that pipe is about 15mm in diameter. But just as it enters the cupboard before a couple of turns to get into boiler it seems about 20mm in diameter. Does that tell you anything?

 

[nickso]

Thanks. BG changed so much I couldn't even tell you. I know little to nothing about boilers. They have visited this boiler a dozen times in 5 years or so. It's a bit like Trigger's broom in that I doubt there is very much of the original thing left. they did get a new seal for it - but then I think the BG engineer said it didn't need changing. No idea why. thing is when they ocme round - s**'s law it rarely makes the noise - or it does a fgentle rumble for a moment and stops again. I wonder if to get Ideal in instead?

dont pay for ideal yourself. if BG cant fix it they will pay for ideal themselves.

i personally would be looking at gas pressures, fan, gas valve, h/e, flue. get them back, the quicker they realise its a problem boiler the quicker it gets fixed.

 

[plummerman]

Hello. Thought there might be someone on here who can diagnose what half a dozen British Gas engineers can't. Our Response 120 has (for the last couple of years) made a very loud rumbling noise from time to time. It usually happens if you switch the hot water tap on in any of the rooms. Now and then it happens when the heating is on. Starts rumbling for no reason (no tap has gone on, no rad valves have been opened or closed). Turing of the tap or turning off the boiler and back on again (advancing the program) fixes it instantly. It will usually happen half a dozen times each day. Sometimes it stops of it's own accord even with hot water running, sometimes you have to turn of the tap. If it starts because of the radiators (no taps on) then it doesn't stop on its own. for your pleasure I put a video on youtube. It stops at the end because the hot tap was switched off. This boiler has been serviced recently. when the boiler rumbles it must also break its seal slightly since CO is produced (enough to make a CO alram in the cupboard flash for a few seconds). the flue has been checked and British Gas said it's fine to use. Any ideas?

http://uk.youtube.com/watch?v=yJ5vdgtBYBU

When you say rumbles? and causes the seals to break. Have you ever witness the outer casing bend. These bag of poo boilers where reknowned for lumpy ignition or as we knew it by explosive so explosive where some of these that vertical flue terminals used to be found 200 yards down the street on an estate in nottingham, this particular estate that had over 400 of these boilers fitted. So bad was the state that my last company had a bloke pretty much stationed on there. If i remember rightly ideal brought out a retro fit flu sensor which you had to drill into the flu and couple upto the gas valve. Has one been fitted?

 

[abrahamlove]

I've no idea if that's been fitted. I've never seen the case bending.

I guess what I really need to do is get BG back and keep them there until it makes the noise. I wonder if to print out this thread to give them some ideas!

 

[BigBurner]

This is the only boiler that has a pre-mix burner and is non-condensing.

These boiler are susceptible to gas inlet pressure and dicky meter regulators. Get them to check the inlet pressures, stand and working pressures and the pressure drop. A slow to react regulator can cause problems.

 

[abrahamlove]

All good stuff. BG will be there this afternoon. *should* be there this afternoon. I'll tell you how it goes.

 

[BGEngineer]

We retro fitted the flue thermostat on every Response we had under contract as well as doing a load for Ideals customers as well, so it is more than likely this has been fitted.

It definately sounds like a supply problem, however I have only had it once where the meter regulator had had it and the working pressure was at 14mb, however the boiler made that rumble from the instant you put it on. As yours is intermittent it maybe difficult to find the fault during our visit.

Changed the heat exchanger on a 120 yesterday, which is the second one in under 4 years, luckily done so many on them now I've got it down to 2hrs

 

[shambolic]

Gas valve sounds as if it is out of calibration (usually shows up on low fire) this gives incorrect air gas mixture leading to this noise and is very intermittent.
Also could be flue seal where the inner flue joins turret elbow. I have had this several times.

Remember under BG contract if boiler under 10 years and been on contract for some time they will replace boiler free of charge (check yer terms and conditions of three star contract)

 

[BGEngineer]

Its actually if the boiler is under 7 years old we will replace, but this is very rare. I have only had to do it once for a Keston before where the heatexchanger needed replacing at a cost of £700. Although I strongly advise getting the boiler changed as they are a heap of c**p, I can pretty much guarantee we wont replace it.

Also I'm pretty sure the inner flue straight of the heatexchanger just mates with the turret and does not require a seal??

 

[nickso]

Gas valve sounds as if it is out of calibration (usually shows up on low fire) this gives incorrect air gas mixture leading to this noise and is very intermittent.

that sounds like a good starting point, remind me whether responses have the same gas valve setup as minimisers, they are pretty unreliable gas valves too.

Also could be flue seal where the inner flue joins turret elbow. I have had this several times.

the early ones dont have a seal there.

Remember under BG contract if boiler under 10 years and been on contract for some time they will replace boiler free of charge (check yer terms and conditions of three star contract)

not unless its deemed too costly to repair. age of contract makes no difference either.

Its actually if the boiler is under 7 years old we will replace, but this is very rare.

just got changed to 10 years this month i believe.