Viessmann FB2B Installation And Service Instructions Manual page 72

Code 1
Heating circuit 1, heating circuit 2, heating...
Parameter address
A5:...
5
6
7
to
15
Coding in the delivered condition
Summer eco function absolute
A6:36 Extended economy mode
disabled
Mixer eco function
A7:0 Without mixer economy
function (only for heating
circuits with mixer)
72
With heating circuit pump logic function: Heating cir-
cuit pump "OFF"
AT > RT + 1 K
set
AT > RT
set
AT > RT - 1 K
set
AT > RT - 9 K
set
Possible change
A6:5
to
A6:35
A7:1
(cont.)
Extended economy control
enabled, i.e. the burner and
heating circuit pump will
stop and the mixer close at
a variable value, adjustable
between 5 and 35 °C plus
1 °C. The base value is the
adjusted outside tempera-
ture. This value is based on
the actual outside temper-
ature and a time constant
that takes the cooling down
of an average building into
consideration.
With mixer economy func-
tion (extended heating cir-
cuit pump logic):
Heating circuit pump also
"OFF":
■ If a mixer has been
attempting to close for
longer than 20 min.
Heating circuit pump
"ON":
■ If the mixer changes to
control function
■ If there is a risk of frost