Alpha 240 eco turning on / off

[nb123]

We have an Alpha Ocean 240 Eco.

On both CH and DHW, the boiler fires correctly, then after about 30 to 40 seconds the boiler flame turns right down for a while and the neon warning light comes on. Then after a while the neon warning light goes off and the boiler flame lights up again.

There are no unusual noises, and during the 'off' time it sounds like the pump is still working ok. The duration of the 'off' time seems to increase as time passes.

For DHW, the water only manages to get like warm before it goes off. For CH, the radiators get warm but not hot, and then cool down slightly before the boiler fires up again.

Any thoughts would be appreciated.

Many thanks.

 

[Alpha man]

I take it that the orange neon comes on?

Either flue Venturis or Air pressure switch or main PCB.

 

[nb123]

Hello Alpha man,

Yes, the orange neon does come on. I've noticed that for CH, the orange neon will flicker for a few seconds before coming on solidly, which is when the burner dies down; whilst for DHW, the light does not flicker at all - it comes on solidly and the burner dies down instantly.

In both cases, when the burner dies down, the boiler doesn't change the noise that it normally makes, it still sounds like it's trying to run, a bit like a formula one car whose revs are throttled back when it enters the pit lane !

I will take your advice and reply later.

NB

 

[nb123]

Alpha man,

Have taken your advice and also given everything a good clean.

The overall situation is much improved, which is very welcome and surprising, as I haven't really done anything !

DHW and CH working nearly ok with just an occassional 'die down'. It also seems to have been getting a bit better as each day has passed. The boiler had been out of action for a few months over the summer, but is now performing quite acceptably.

Thank you for your time.

NB

 

[Alpha man]

My pleasure NB.