Viessmann Vitocrossal 300 Service Manual page 68

Coding 2
Solar
(continued)
Coding in the factory setting
11:50
12:10
20:0
22:8
68
Set DHW tank temperature for
solar 122°F (50°C).
- Target temperature control
switched on (code 10:1):
Temperature at which the solar
heated water in the DHW tank
is to be stratified.
- Extended control functions set
to heat two DHW tanks (code
20:8):
If the actual temperature of a
DHW tank reaches the selected
set DHW tank temperature,
heating is switched to the
second DHW tank.
Minimum collector temperature
68°F (20°C).
The solar circuit pump is only
started when the set minimum
collector temperature is exceeded
at the collector temperature
sensor.
No extended control functions
enabled.
Start temperature differential
for central heating backup: 8 K.
(code 20:4 must be selected)
Vitocrossal 300 CU3A 26 to 57 Service
Possible change
11:10 The set DHW tank temperature for
to solar can be adjusted from 50 to
11:90 194°F (10 to 90°C).
12:0 Minimum collector temperature
function switched off.
12:1 Minimum collector temperature
to adjustable from 34 to 194°F
12:90 (1 to 90°C).
20:1 Auxiliary 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
to for central heating backup is
22:30 adjustable from 21 to 30 K.