Viessmann Vitotronic 300 Installation And Service Instructions Manual page 73

Vitotronic 300, GW5B Installation and Service
"Solar" Group
(continued)
Coding in the delivered condition
12:20 Minimum collector temperature (minimum
start temperature for the solar circuit pump)
68°F (20°C).
20:0 No extended control functions enabled.
22:8 Start temperature differential with central
heating backup (code "20:4" must be
selected) 8 K.
23:4 Shutdown temperature differential with
central heating backup (code "20:4" must
be selected) 4 K.
24:40 Start temperature for thermostat function
(code "20:5" or "20:6" must be selected)
104°F (40°C).
25:50 Shutdown temperature for thermostat
function (code "20:5" or "20:6" must be
selected) 122°F (50°C).
26:1 Priority for DHW tank 1 with alternate
heating. (Code "20:9" must be selected).
27:15 Alternate heating time 15 min. The DHW
tank without priority is heated at most for the
duration of the set alternate heating time if
the DHW tank with priority is heated up.
28:3 Alternate pause time 3 min. After the
selected alternate heating time for the DHW
tank without priority has expired, the rise in
collector temperature is captured during the
alternate pause time.
Possible change
12:0 No minimum limit enabled.
12:1 Minimum collector temperature adjustable from 1
to to 194°F (90°C).
12:90
20:1 Additional function for DHW heating.
20:2 Differential temperature control 2.
20:3 Differential temperature control 2 and
auxiliary function
20:4 Differential temperature control 2 for
central heating backup.
20:5 Thermostat function.
20:6 Thermostat function and auxiliary function.
20:7 Solar heating via external heat exchanger without
additional temperature sensor.
20:8 Solar heating via external heat exchanger
with additional temperature sensor.
20:9 Solar heating of two DHW tanks.
22:2 Start temperature differential adjustable from
to 2 to 30 K.
22:30
23:2 Shutdown temperature differential adjustable
to from 1 to 29 K.
23:30
24:0 Start temperature for thermostat function
to adjustable from 0 to 100 K.
24:100
25:0 Shutdown temperature for thermostat function
to adjustable from 0 to 100 K.
25:100
26:0 Priority for DHW tank 1 without alternate heating.
26:2 Priority for DHW tank 2 without alternate heating.
26:3 Priority for DHW tank 2 with alternate heating.
26:4 Alternate heating without priority for either DHW
tank.
27:5 The alternate heating time is adjustable from
to 5 to 60 min.
27:60
28:1 The alternate pause time is adjustable from
to 1 to 60 min.
28:60
Code 2
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