Viessmann VITOCAL 300-A Installation And Service Instructions Manual page 149

Hysteresis/Hysteresis booster heater
A Set DHW temperature
B Heat pump switching hysteresis
("Hysteresis")
C Switching hysteresis, instanta-
neous heating water heater
("Hyst. booster heater")
D Actual DHW temperature at the
upper cylinder temperature sen-
sor
E Heat pump control state
F Instantaneous heating water hea-
ter control state
G OFF
H ON
Delivered condition
Setting range
(cont.)
Note
The value selected for "Hysteresis"
should be higher than the expected
temperature drop due to heat losses
during reduced mode (approx. 5 K).
A lower value for "Hyst. booster hea-
ter" increases the proportion of DHW
heating by the external heat source.
Press the following keys:
1. "Device settings".
2. "Programming".
3. "DHW".
4. y/x for "Hysteresis"
5. T/U for the selected value.
6. "BACK"
Hysteresis
7.0 K
1.0 to 10.0 K
DHW control settings
(6007)
or
"Hyst. booster hea-
ter" (6008).
to confirm.
Hysteresis boos-
ter heater
10.0 K
2.0 to 30.0 K
149