Ferroli Optimax HE 31C: Intermittent hot water

[I.Cannon]

Heating works fine, hot water never gets to full temperature, eventually runs cold. If the hot water is ran for long enough it will eventually get lukewarm then back to cold and repeat the cycle, never getting fully hot nor fully cold.

When running the hot water, it slowly gets hot but never to the temperature set to (I've tried setting to both min and max water temperature, neither made any difference). The water then slowly cools to barely above that of the cold water tap.

Temperature readout on the boiler is accurate, the boiler knows the water isn't hot and never reaches 40 degrees celsius. Something is clearly making it shut off early. The burner can also be heard to lower and stop heating the water.

Replaced domestic heat exchanger

Fitted a replacement flow meter.

Boiler is only just over 5 years old and just out of warranty by 2 months, so sadly I'm out of luck on free repairs.

It could be the diverter but it doesn't seem to be as far we can tell.

My Father is the plumber gas safe registered etc, I'm just posting on his behalf, kinda, as it's my boiler.

 

[lame plumber]

get dad to fix it, have a look at the site rules please

 

[Ermintrude]

get dad to fix it, have a look at the site rules please

Doh your not in the north east are you?

 

[I.Cannon]

I had read them, just misunderstood the specifics as there are old archived posts in which people have speculated various faults with this boiler model.

My dad will be phoning a ferroli rep tomorrow anyway, I was just hoping for any advice on which direction to point him, as the rep was sure it would be the flow meter.

I doubt he has the patience with computers to register himself, get 10 posts, then contact an admin to get his gas safe credentials checked out. I'll try and sell the idea to him.

Kinda worried how this reads now, I'm not a kid at home. I'm a computer science graduate who left home a decade ago. So I fix his computer, he fixes my boiler =p I understand the need to keep such advice among those qualified, consequences of getting things wrong a far more serious than if I forget to plug in a cpu fan.

 

[I.Cannon]

Doh your not in the north east are you?

I assume you mean me rather than lame plumber who's link in sig shows him as being from the south west near exeter.

I live near Durham. Dad is Hartlepool.