Resetting Operating Parameters To Their Delivered Condition - Viessmann Vitocrossal CRU 800 Service Instructions For Contractors

Burner control unit VUC 310
Example: Changing the maximum operational
burner output
Press the following buttons:
1. S longer than 2 s; " " flashes.
2. until "6" is shown under "Service".
3. S to confirm; "6" is shown under "Status". "1" is
shown under "Service".

Resetting operating parameters to their delivered condition

1. S longer than 2 s, " " flashes.
2. until "6" is shown under "Service".
3. S to confirm; "6" is shown under "Status". "1" is
shown under "Service".
4. until "0" is shown under "Service".
Setting the modulation level for manual operation
The modulation level can be temporarily adjusted for
carrying out tests and settings on the gas train, e.g.
setting the max. heating output range.
During this manual operation the demands from the
Vitotronic control unit have no effect.
To call up the service display the burner must be run-
ning.
Press the following keys:
1. +S simultaneously for longer than 2 s.
The burner switches to manual mode. "P" is
shown under "Status". The current modula-
tion level flashes under "Service".
(cont.)
4. S
5. /
6. S
7. S
5. S "1" is shown under "Status" and "dEL" under
6. S to confirm. If reset successfully, "1" is shown
7. S to change to the operating display.
2.
3.
4. +S simultaneously for longer than 2 s.
to confirm; "1" is shown under "Status". The
current value for the maximum operational out-
put in % is shown under "Service".
for the required maximum operational output.
to confirm. If adopted successfully, "1" appears
under Service; if it failed, "0" will appear.
to change to the operating display.
"Service".
under Service; if it failed, "0" is shown.
until the required lower heating output is
shown under "Service", e.g. "0" for minimal
lower heating output.
Tests and settings for operation at the lower
heating output can now be carried out.
until the required upper heating output is
shown under "Service", e.g. "100" for maxi-
mum upper heating output.
Tests and settings for operation at the upper
heating output can now be carried out.
Manual operation is terminated.
Burner control unit
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