Viessmann VITODENS 300 Service Instructions Manual page 55

Code 2
(cont.)
Coding in the delivered condition
Boiler circuit, mixer circuit
A6:36 * 1 Extended economy
mode disabled
A7:0 * 1 Without mixer econo-
my function
A8:1 * 1 Heating circuit M2
(mixer circuit) creates a
demand for the internal
circulation pump
*1
Only for weather-compensated control units.
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, which is
adjustable between 5 and
35 °C plus 1 °C. This
value is based on the ad-
justed outside tempera-
ture, comprising the
actual outside tempera-
ture and a time constant,
which takes the cooling
down of an average
building into considera-
tion.
A7:1 With mixer economy
function (extended heat-
ing circuit pump logic):
Heating circuit pump also
OFF, if the mixer was
moved to the closed posi-
tion for longer than
20 min. Heating pump
ON,
if the mixer changes to
control mode
or
after cylinder heating
(for 20 min)
or
if there is a risk of frost.
A8:0 Heating circuit M2 (mixer
circuit) creates no de-
mand for the internal cir-
culation pump
Coding
55