Enable Instant. Heating Water Heater For Central Heating - Viessmann VITOTRONIC 200 Service Instructions Manual

7901 Enable electric heaters for DHW heating
Value Meaning
"0" Instantaneous heating water heater of the lag
heat pump is not enabled for DHW reheating.
The instantaneous heating water heater is on-
ly switched on for the purpose of DHW cylin-
der frost protection.
"1" Instantaneous heating water heater is ena-
bled for DHW reheating.

7902 Enable instant. heating water heater for central heating

If the set flow temperature cannot be achieved with the
heat pump, an instantaneous heating water heater
installed in the secondary circuit flow can be started for
central heating.
Note
The instantaneous heating water heater must be ena-
bled separately with parameter "Enable instantane-
ous heating water heater 7900".
7905 Start delay instantaneous heating water heater
Only applies to central heating.
Within the set period the instantaneous heating water
heater will not start under the following conditions:
After a change of operating status
■
After a change from DHW heating to central heating
■
During this period, the heat pump control unit does not
calculate the output integral (integral from duration and
extent of deviation of set temperature to actual temper-
ature) that is crucial for the start-up.
7907 Max. output instantaneous heating water heater
Value Meaning
"1" Output stage 1, e.g. approx. 3 kW
"2" Output stage 2, e.g. approx. 6 kW
"3" Output stages 1 and 2 simultaneously, e.g.
approx. 9 kW
Parameter group Electric booster heater
!
(cont.)
Value Meaning
"0" Instantaneous heating water heater is not en-
abled for central heating.
"1" Instantaneous heating water heater is ena-
bled for central heating.
!
Note
Only if there is a very high heat demand will the control
unit switch on the instantaneous heating water heater
within the set start delay, for example to provide frost
protection.
Setting in min
!
225