Noisy ferroli optimax 30he when in CH mode

[Daz123]

Hi all, I was wondering if anybody had any ideas why said boiler is making whining high pitch noises in CH mode. I can pinpoint the noises to around the plate exchanger and diverter valve .Pump seems to be purring nicely and noises are worse when selector switch is on 3 , goes quieter on 2. Draw off DHW and the noise disappears. F & R valves are fully open !!!!.:confused5::confused5:

 

[jam1979]

Bleed ur pump a
nd see what that does

 

[Daz123]

Bleed ur pump a
nd see what that does

Tried it mate , no air in pump. Thanks anyways

 

[scorps]

I've come across this problem with the same boiler.The owner got Ferroli out, their engineer said the gas pressure was too high,so turned it down the noise stopped,but when winter came the hot water was luke warm Ferroli came back out and said the gas pressure's wrong and turned it back up,water got hot but whining noise re-appeared on heating for first 15 mins of being on.I was doing a plumbing job and he asked me to look at it, I rated the heating down to suit size of house and it seemed to be ok,

 

[Dotty]

Too much info now.

going into the private forum.