Boiler - Viessmann FB2A Installation And Service Instructions For Contractors

General
(cont.)
Coding in the delivered condition
Ext. Heating program changeover to heating circuit
91:0 No external heating pro-
gram changeover via
external extension
Set flow temperature in case of ext. demand
9b:0 No minimum flow temper-
ature in case of external
demand

Boiler

Coding
Coding in the delivered condition
Burner service in 100 hours
21:0 No maintenance interval
(hours run) selected
Service interval in months
23:0 No time interval for
burner service
Possible change
91:1 The external heating pro-
gram changeover affects
the heating circuit without
mixer
91:2 The external heating pro-
gram changeover affects
the heating circuit with
mixer
91:3 The external heating pro-
gram changeover affects
the heating circuit without
mixer and the heating cir-
cuit with mixer
9b:1 Set value for minimum flow
to temperature in case of
9b:127 external demand, adjusta-
ble from 1 to 127 °C (limited
by boiler-specific parame-
ters)
Possible change
21:1 The number of hours run
to before the burner should
21:100 be serviced is adjustable
from 100 to 10 000 h
One adjusting step ≙ 100
h
23:1 Interval adjustable from 1
to to 24 months
23:24
Code 1
63