I am hoping someone can help..? My Vailant Ecomax combi bolier kettles when the hot water comes on, on the timer or when we run a bath/shower. It only comes on with the hot water, not the central heating. When it starts making the noise, I can make it stop by turning the heating on with the thermostat (turning it on to trigger the heating coming on). The noise will stop within within about 10-20 seconds and then I can turn the thermostat back down again and it stays quiet. I have already added boiler noise reducer to the central heating, but this has not helped with the noisy hot water. I have also had the heat exchanger replaced with a new one (the old one was quite blocked). Can anyone tell me how to fix this?
Boiler kettling on hot water only
- Thread starter fridayman
- Start date
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How long ago did it block? Does the temperature display raise right up to the high 70c's when its noisy? Good chnace its blocked again unless you did something about the debris that blocked the old heat exchnager. Silencer wont solve the problem.
The boiler did this right after the new heat exchanger was fitted (less than 6 months ago). I have also drained and refilled the central heating twice (the water comes out pretty clear now). I am not sure how to drain the hot water side??
I have just checked: when I turn the hot water on, the temp on the boiler builds up to about 69 over about 10 seconds, then it dropped back down to around 45 for another 10 seconds before rising again to the mid 60's (when it started making the noise).
Is it possible the hot water side only is blocked? I have tried several treatments to remove rust, sludge, scale by adding them to the open top up tank, and some fernox straight into the radiators once.
I find it very odd that I only have to turn the central heating on for a few seconds to make the noise go away.
I have just checked: when I turn the hot water on, the temp on the boiler builds up to about 69 over about 10 seconds, then it dropped back down to around 45 for another 10 seconds before rising again to the mid 60's (when it started making the noise).
Is it possible the hot water side only is blocked? I have tried several treatments to remove rust, sludge, scale by adding them to the open top up tank, and some fernox straight into the radiators once.
I find it very odd that I only have to turn the central heating on for a few seconds to make the noise go away.
What you have described sounds like a blockage. It may or may not be in heat exchanger.
Which heat exchanger was changed? Main or HW?
By turning the heating on you are dispursing the heat down the heating pipe and cooling the boiler.
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If it was the main, big round one, then its likely the wrong one was changed i imagine.
The hot water heat exchanger can be easily removed and either cleaned or replaced. Removal and refitting is detailed in the manufacturers instructions.
The hot water heat exchanger can be easily removed and either cleaned or replaced. Removal and refitting is detailed in the manufacturers instructions.
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