Pulsing / Vibrating After Heating Switched Off

[EuroRick84]

Hi!

I have a Vokera Linea 28HE combi condenser boiler.

The boiler operates almost silently when heating water for DHW or central heating. When the thermostat switches the heating pump off, the boiler stops heating the water and enters its cool-down process for a few minutes.

Recently, at the end of this process, there are two or three loud, resonant vibrations which rumble through the house, as if a car is being revved a couple of times, after which the boiler is silent and ready for its next go.

What might these vibrations be?

Thanks

Rick

 

[Gas2Air]

You have a **** boiler.

 

[Tibbot]

Could be a built in by-pass causing noise. This did happen on earlier models that used a similar hydroblock. Check instruction booklet.

 

[mpheating]

check boiler with flue gas analyser and make sure that co2 max and min readings are spot on, had similar problem with a Worcester which was 2 years old, was the min pressure. gave similar problems as you describe. worth a shot.

 

[EuroRick84]

Thanks, both of you.

I shall get onto my heating engineer with both hypotheses and see what's up.