WB greenstar CDi- is this a fault code?

[Ltnman]

Turned the boiler on for heat for the first time since a boiler service which seemed more of a safety check and nothing else.

Boiler took maybe 20 minutes to get from 37C to 65C with the temperature alternating between the temperature and the photo shown. Anyone got a theory why it took so long to get to temperature? This event happened after I called for heat and then straight away my son took a shower. The 20 minute lag occurred after the shower was turned off as I know the heating shuts down on taking a shower.

 

[kidgreen61]

This is what they call siphon fill mode. It will do it every time the boiler is switched off. It will resume normal service after around 15 mins.

 

[Ltnman]

Top man, thanks!

 

[ianmcd]

as already advised , not a fault code and nothing to worry about, will happen every time power is switched off to the boiler