Viessmann Compact Flame symbol

[desktop987456]

I have a Viessmann compact heat only boiler used for Central Heating only.

Issue: When boiler starts (even from cold) the flame intensity or level stays on minimum on display (see attached picture).

I have been advised by Viess Tech support to notch up the CH dial but even on setting 6 the flame level doesn't change. It keeps on running at low setting to reach the desired level set by thermostat but is very slow to heat the rads.

I have reset the boiler a number of times with no luck. If I go into 'Serv' mode of boiler, the flame intensity goes up or down if I rotate the CH dial clockwise or anticlockwise. If I restart the boiler after getting out of Serv mode it keeps firing at minimum flame setting.

Any ideas? Thanks in advance.

 

[fixitflav]

I have a Viessmann compact heat only boiler used for Central Heating only.

Issue: When boiler starts (even from cold) the flame intensity or level stays on minimum on display (see attached picture).

I have been advised by Viess Tech support to notch up the CH dial but even on setting 6 the flame level doesn't change. It keeps on running at low setting to reach the desired level set by thermostat but is very slow to heat the rads.

I have reset the boiler a number of times with no luck. If I go into 'Serv' mode of boiler, the flame intensity goes up or down if I rotate the CH dial clockwise or anticlockwise. If I restart the boiler after getting out of Serv mode it keeps firing at minimum flame setting.

Any ideas? Thanks in advance.

If I didn't recognise the name, I'd have referred you to the other thread!

 

[desktop987456]

For anyone with flame intensity stuck at the lowest level on vitodens; see attached.

Even though the instructions apply to combi variant, I can confirm that it also worked on heat only version of the vitodens as well and after following the instructions the CH dial now behaves as it should!

Viessmann Tech support told me that its either plate HEX or Gas control valve.