Fujitsu Super High Power Series Design & Technical Manual page 80

• Release integral electric flow
After the release of the 1
ture measured with the point of engagement and forms as integral and includes a possible deficit
of heat. Once the value of the integral reaches the maximum value (line 2882), the 2
engaged (heater 1: off, heater 2: control). The controller continuously compares the temperature
measured at the point of engagement and new features to deficit of heat in the full release. When
the full release reaches the value set (line 2882), the 3
on, heater 2: control).
• Release electric flow below OT
The heater will be activated only if the attenuated outdoor temperature is below the temperature
set here.
WARNING
If this setting value is too low, there may be a feeling of discomfort due to the fact that the heat
pump is unable to meet the heating requirements alone at low outdoor temperatures, and heaters
are switched on.
• Compensation heat deficit
This function compensates for excess heat and heat deficits. These can occurs in the following
situations:
– Minimum compressor on and off times
– In the case of low temperature requests, the flow temperature can lie below the required set-
point, but the return temperature may not drop below the switch-on point for a longer period of
time. In this situation, the heat pump must be switched on to prevent heat deficits.
The controller compares continuously the flow temperature setpoint with the actual value and inte-
grates the surplus heat and heat deficits. Differences are compensated for by extending the com-
pressor on and off times.
If the compressor is not switched on or off due to surplus heat or heat deficits, the controller dis-
plays an appropriate status message.
When this function is not active during the time, the DHW storage tank is charged. The function is
not active either in the case of plants with buffer/(combi) storage tanks.
"Compensation heat deficit" only acts in heating mode. The parameter is inactive in cooling mode.
The maximum switch-off temperature is given priority over the "Compensation" function. In the
case of sudden setpoint changes, both integrals are cleared.
– Behavior in connection with the Floor curing function
When activating the floor curing function, the integral is set to a level representing 1.5 times the
predefined value (factory setting). If the current temperature lies at least 2 K below the required
setpoint, the heat pump is immediately switched on. If compensation of surplus heat or heat
deficits shall act "Only with floor curing fct", the respective setting must be selected. This means
that the parameter is deactivated in normal heating mode.
– Calculation of integral
If a flow temperature sensor (Bx1) is connected and the heating curve is set to the flow tempera-
ture setpoint, the controller uses the flow temperature and the flow temperature setpoint for
computing the integrals.
In the following situations, the integrals is set to "0":
• No valid temperature request delivered
• Setpoint change > 2 K
• Frost protection for the heat pump is active
• The heat pump has gone to lockout or cannot deliver any heat for a longer period of time
• The heat pump is in active cooling mode
• A buffer storage tank is being charged
• The function is deactivated
With active DHW charging, the integral value is frozen.
3-8. Heat pump functions
st
stage (heater 1: on, heater 2: off), the controller compares the tempera-
- (03-36) -
rd
stage of the heater is triggered (heater 1:
nd
stage is
3. Function table