Viessmann MatriX Service Instructions Manual page 27

Gas burner control unit
Manual mode and service display
A heat demand is required through the control unit to call up the service
display and to operate in manual mode.
The actual level of modulation in % is shown in the service display;
whereby:
"d 00" is the lower output
and
"d 00." (with the full stop after the last digit) is the higher output.
1. Press b and S simultaneously;
the burner will switch to manual
mode. The display shows "d"
under Status.
Status Service
2. Adjusting the lower output:
Press b, until the display
shows "d 00".
3. Adjusting the higher output:
Press a, until the display
shows "d 00.".
4. Press b and S simultaneously;
the burner will revert to
modulating mode.
Initial start−up, inspection and maintenance
(cont.)
27