Daikin Altherma 3 R W Installer's Reference Manual page 59

Depending on the installed type of heat emitters (radiators, heat
pump convector, underfloor loops) or situation, you can change the
difference between entering and leaving water temperature.
Note: : The pump will regulate its flow to keep the delta T. In some
special cases, the measured delta T can differ from the set value.
INFORMATION
When only the backup heater is active in heating, delta T
will be controlled according to the fixed capacity of the
backup heater. It is possible that this delta T is different
from the selected target delta T.
INFORMATION
In heating, the target delta T will only be achieved after
some operation time, when the setpoint is being reached,
because of the big difference between leaving water
temperature setpoint and inlet temperature at startup.
INFORMATION
If the main zone or the additional zone has a heating
demand, and this zone is equipped with radiators, then the
target delta T that the unit will use in heating operation will
be 10°C fixed.
If the zones are not equipped with radiators, then in
heating the unit will give priority to the target delta T for the
additional zone, if there is a heating demand in the
additional zone.
In cooling the unit will give priority to the target delta T for
the additional zone, if there is a cooling demand in the
additional zone.
# Code
[2.B.1] [1‑0B] Delta T heating: A minimum
temperature difference is required for
proper operation of heat emitters in
heating mode.
▪ If [2-0C]=2, this is fixed to 10°C
▪ Else: 3°C~10°C
Delta T cooling: A minimum
[2.B.2] [1‑0D]
temperature difference is required for
proper operation of heat emitters in
cooling mode.
▪ 3°C~10°C
Leaving water temperature: Modulation
Only applicable in case of room thermostat control.
When using the room thermostat functionality, the customer needs
to set the desired room temperature. The unit will supply hot water to
the heat emitters and the room will be heated.
Additionally, also the desired leaving water temperature must be
configured: if Modulation is enabled, the unit automatically
calculates the desired leaving water temperature. These calculations
are based on:
▪ the preset temperatures, or
▪ the desired weather-dependent
dependent is enabled)
Moreover, with Modulation enabled, the desired leaving water
temperature is lowered or raised in function of the desired room
temperature and the difference between the actual and the desired
room temperature. This results in:
▪ stable room temperatures,
temperature (higher comfort level)
▪ less on/off cycles (lower noise level, higher comfort and higher
efficiency)
ERGA04~08DAV3(A) + EHBH/X04+08DA
Daikin Altherma 3 R W
4P496758-1B – 2019.10
Description
temperatures (if weather-
exactly matching the desired
▪ water temperatures as low as possible to match the desired
temperature (higher efficiency)
If Modulation is disabled, set the desired leaving water temperature
via [2] Main zone.
# Code
[2.C.1] [8‑05] Modulation:
▪ 0 No (disabled)
▪ 1 Yes (enabled)
Note: The desired leaving water
temperature can only be read out on
the user interface.
[2.C.2] [8‑06] Max modulation:
▪ 0°C~10°C
This is the temperature value by which
the desired leaving water temperature is
increased or decreased.
INFORMATION
When leaving water temperature modulation is enabled,
the weather‑dependent curve needs to be set to a higher
position than [8-06] plus the minimum leaving water
temperature setpoint required to reach a stable condition
on the comfort setpoint for the room. To increase
efficiency, modulation can lower the leaving water setpoint.
By setting the weather‑dependent curve to a higher
position, it cannot drop below the minimum setpoint. See
the illustration below.
T t
+[8-06]
−[8-06]
a Weather-dependent curve
b Minimum leaving water temperature setpoint required to
reach a stable condition on the comfort setpoint for the
room.
Shut off valve
The following is only applicable in case of 2 leaving water
temperature zones. In case of 1 leaving water temperature zone,
connect the shut-off valve to the heating/cooling output.
The shut off valve for the main leaving water temperature zone can
close under these circumstances:
INFORMATION
During defrost operation, the shut-off valve is ALWAYS
opened.
During thermo: If [F‑0B] is enabled, the shut off valve closes when
there is no heating demand from the main zone. Enable this setting
to:
▪ avoid leaving water supply to the heat emitters in the main LWT
zone (through the mixing valve station) when there is request from
the additional LWT zone.
▪ activate the ON/OFF pump of the mixing valve station ONLY when
there is demand.
8 Configuration
Description
a
b
T a
Installer reference guide
59