Viessmann Vitoladens 300-W Service Instructions For Contractors page 50

Codes
Code 2
(cont.)
Coding in the delivered condition
Boiler circuit, mixer circuit
A6:36 Extended economy mode
disabled
A7:0 Without mixer economy
function
A8:1 Heating circuit with mixer
M2 creates a demand for
the internal circulation
pump
A9:7 With pump idle time:
Heating circuit pump OFF
in case of set value mod-
ification (by changing the
operating mode or the set
room temperature)
50
Possible change
A6:5 Extended economy mode
to is enabled, i.e. the burner
A6:35 and heating circuit pump
will be switched OFF and
the mixer will be closed at
a variable value that is
adjustable between 5 and
35 °C plus 1 °C. This value
is based on the adjusted
outside temperature, com-
prising the actual outside
temperature and a time
constant that takes the
cooling down of an average
building into consideration.
A7:1 With mixer economy func-
tion (extended heating cir-
cuit pump logic):
Heating circuit pump also
"OFF":
If a mixer has been closed
for longer than 20 min.
Heating pump "ON":
■ If the mixer changes to
control function
■ If there is a risk of frost
A8:0 Heating circuit with mixer
M2 creates no demand for
the internal circulation
pump
A9:0 Without pump idle time
A9:1 With pump idle time;
to adjustable from 1 to 15
A9:15