Boiler efficiency question

[frolingdual]

I have read that efficiency is best if a boiler is operated at full load. This shouldn't be a problem for mine as I have quite a large buffer tank.

What I have noticed is that it runs at its flue set point of 180 deg C. It also keeps the boiler at its setpoint of 80deg C. So that seems good.

But it's fan is only operating at about 60%.Does this mean it isn't running at full load? Hence is inefficient?

I have chains in the heat exchange pipes and wonder if I should put bigger ones in?

 

[MadMax31]

Ill take a stab...

Fan at %60 is to maintain flue setpoint. Larger chains equalls more mass to retain heat from said flue gas. Is your combustion fan on a drive, AFD/VFD or is damper at %60?

Ive always been impressed with the UK residential heating market just walking all over ours. What Wiesshaupt has done for oil burners is impressive.

 

[frolingdual]

Ill take a stab...

Fan at %60 is to maintain flue setpoint. Larger chains equalls more mass to retain heat from said flue gas. Is your combustion fan on a drive, AFD/VFD or is damper at %60?

Ive always been impressed with the UK residential heating market just walking all over ours. What Wiesshaupt has done for oil burners is impressive.

The fan is variable speed. I'm not sure you would be impressed if you lived here.The uk government set up some very large grants for people to install pellet boilers but then rapidly reduced them. The company that installed mine with 5 year service and warranty went bust within a few months of installation blaming the grant reductions. The boiler itself is Austrian.