Fujitsu WSYA050ML3 Design & Technical Manual page 87

• Room temperature limitation setback
The room temperature limitation function enables shutting off the cooling circuit pump if the room
temperature falls below the adjusted room temperature setpoint (with summer compensation: line
920) by more than the adjusted differential.
The cooling circuit pump is reinitialized as soon as the room temperature rises again above the
current room temperature setpoint. If the room temperature limitation function is active, no cooling
demand will be transmitted to production.
The function is deactivated if:
– No room temperature sensor is available.
– Room influence limitation is set to "---".
– Room influence (line 928) is set to "---% (Simple control according to outdoor conditions)".
• Mixing valve control
– Mixing valve decrease:
The cooling demand issued by cooling circuit 1 to production is reduced by the adjusted value. If
there is a second zone, this reduction should enable the second zone to be cooled. To achieve
this result, the sub-cooling must be determined in accordance with the type of emitter and "with
primary controller/system pump" (line 963) must be set to "yes" to switch on the pump for the
second zone.
Zone 1: Heating/Cooling floor
Zone 2: Fan coils
Zone 1: Heating/Cooling floor
Zone 2: HCF
WARNING
In these settings are not chosen properly, the heat pump may stop automatically due to the
flow temperature being too low. A safety mechanism is triggered at 6°C to protect the exchang-
er from freezing.
– Actuator running time:
For the 3-position servomotor used, it is possible to adjust the travel time. With a 2-position ser-
vomotor, the adjusted travel time is inoperative.
– Mixing valve heating mode:
Determines the position of mixing valve 1 (Y1/Y2) during heating operation is activated. This pa-
rameter is inoperative in installations where heating and cooling circuits are hydraulically sepa-
rate.
• Control: The valve controls in heating and cooling mode.
• Open: The valve controls in cooling, and is open in heating mode.
3-5. Cooling circuit 1 functions
Line
932 Room temperature limitation
Line
938 Mixing valve decrease
941 Actuator running time
945 Mixing valve in heating mode
Line 938 = 10°C, with line 924 =
18°C
Line 963 = yes
Line 938 = 0°C, with line 924 = 18°C
Line 963 = yes
Function
Function
Configuration
- (03-29) -
How the configuration affects
control
With a 35°C outdoor temperature,
the flow setpoint will be 18°C -
10°C (i.e. 8°C).
While in the first zone (HCF) it will
be 18°C through action of the
mixing valve.
With a 35°C outdoor temperature,
the flow setpoint will be 18°C in
the both zones.
3. Function table