Dhw Storage Tank Functions - Fujitsu WSYA050ML3 Design & Technical Manual

3-12. DHW storage tank functions

Line Access
5024 S Switching differential
S Charging time limitation
5030
(with dynamic radiator, adjust 40 minutes)
5055 S Re-cooling temperature
5057 S Re-cooling collector
Electric immersion heater
5061 S
release
5093 S With solar integration
DHW charging at the nominal setpoint temperature (line 1610) always takes place in two stages. In
the first stage, only the heat pump heats the DHW tank. The power supplied during this time is at its
peak. Then, when the heat pump is no longer able to supply enough heat to reach the setpoint val-
ue, it switches on the DHW tank heater if authorized. The heater will be cut off when charging is
complete. While the DHW tank charging process via the electric heater is finishing, the heat pump
resume heating.
• Charging control
– Switching differential: If the DHW temperature is lower than the current setpoint minus the dif-
ferential set here, the DHW charging process is launched. It ends when the temperature reach-
es the current setpoint.
NOTE: Forced charging is triggered on the first DHW release of the day. Charging is also
launched when the DHW temperature is within the differential, and as long as it is not
less than 1K above the setpoint.
– Charging time limitation: During charging, the room heating may be stopped or insufficient.
Therefore it is often advisable to limit the charging process timewise to enable heating. If "---"
has been selected the charging time limitation will be deactivated. The DHW will be heated to
the nominal setpoint, even if the room heating has not received enough power in the meantime.
If a value between 10 and 600 is selected, charging will be suspended after the time period set
in minutes, and will remain suspended over that time before resuming. The generator power re-
mains available in the meantime to heat the room. This cycle is repeated until the DHW nominal
setpoint has been reached.
NOTE: When the room heating is stopped (summer mode, economy function, etc.), DHW
charging remains active, regardless of the setting.
• Re-cooling
– Re-cooling temperature: An activated re-cooling function remains in operation until the set re-
cooling temperature in the DHW storage tank is reached.
– Re-cooling collector: When the collector is cold, surplus energy can be emitted to the environ-
ment via the collector's surface.
3-12. DHW storage tank functions
Function
Line
5024 Switching differential
5030 Charging time limitation
Line
5055 Re-cooling temperature
5057 Re-cooling collector
Setting range or display
0...20°C
10...600 minutes
10...95°C
Off Summer Always
24h/day
Release of DHW
Program 4/DHW
No, Yes
Function
Function
- (03-43) -
Setting Factory
increment setting
1°C 7°C
10 minutes 90 minutes
1°C 65°C
Summer
Release of
DHW
Yes
3. Function table