Settings
Installation manual – System controller
35
5
For heating circuit 1
1. If needed, follow instructions in Paragraph 4.1.1 p. 28
to access the complete parameter list, then access
Time prog heating/cooling 1 menu.
2. Select the Set time program field, then follow the
instructions provided in the System controller User
manual to proceed with programming.
For heating circuit 2
1. Proceed the same way, but using the Time program
heating/cooling 2 menu.
5.1.4
Setting the heating curve slope and min/
max outlet water setpoint
To set the heating curve slope for a heating circuit, re-
fer to Figure 5.1
p. 36 and select the curve that passes
through the circuit's design point (water outlet setpoint
required at the minimum outdoor design temperature,
with reference to the room temperature setpoint 20 °C).
For example, if the minimum outdoor design temperature
is – 5 °C and the circuit requires a water outlet tempera-
ture in these conditions of 55 °C to maintain a 20 °C room
temperature, set the slope to 1.5.
To avoid reaching too high temperatures in unexpectedly
harsh climate conditions, we recommend setting the Flow
temp setpoint max parameter to a suitable value. As a
first general criterion, set this parameter to a value that
ensures the system and building will not be damaged.
Special care must be taken in the case of floor
heating systems. It is best to ask the system installer
and the flooring vendor for advice, especially for
parquet floors. Moreover, for floor heating systems
it is recommended that the heating be supplied by
a mixed heating circuit.
Furthermore, except for cases in which the system will be
operated exclusively with the auxiliary boiler at high ther-
mal loads (i.e. the system is intended to run at a higher wa-
ter temperature setpoint than the operating limit of the
K18 heat pump), we recommend setting this parameter
to no more than 65 °C.
To optimise the heating service with certain room heat
exchangers (for example, ducted hot air or fan coil heat-
ing) it is often also worth setting the value of the Flow
temp setpoint min parameter to ensure sufficient heat
exchange in all room conditions.
Since the efficiency of the K18 heat pump (GUE,
Gas Utilization Efficiency) is greater the lower the
water temperature, it is good to set these parame-
ters to the lowest value compatible with the needs
of distribution. This enables you to get the most
out of heating curve operating mode, and boosts
efficiency.
To set the heating curve slope and the flow temp setpoint
min and max of heating circuit 1, proceed as described in
Paragraph 5.1.1
p. 33 to edit parameters 720 (Heating
curve slope), 740 (Flow temp setpoint min) and 741
(Flow temp setpoint max); for heating circuit 2, proceed
as described in Paragraph 5.1.2
p. 34 to edit parameters
1020 (Heating curve slope), 1040 (Flow temp setpoint
min) and 1041 (Flow temp setpoint max).
Be careful not to change the factory setting
(Unused) of parameters 742 and 1042 (Flow temp
setpoint room stat).
