Domestic Hot Water Control; Reheat Mode; Scheduled Mode; Scheduled + Reheat Mode - Daikin Altherma 3 GEO EGSAH06UDA9W Operation Manual

3 Operation
2 Adjust the desired leaving water temperature.
a b
2
35
°C
Main zone
a b
3
45
°C
Additional zone
a Actual leaving water temperature
b Desired leaving water temperature
3.5

Domestic hot water control

3.5.1

Reheat mode

In reheat mode the DHW tank continuously heats up to the
temperature shown on the home screen (example: 50°C) when the
temperature drops below a certain value.
T t
1
60°C
50°C
40°C
15°C
00:00 07:00
T DHW tank temperature
t
t Time
INFORMATION
When the DHW tank mode is reheat, the risk for capacity
shortage and comfort problem is significant. In case of
frequent reheat operation, space heating/cooling function
is regularly interrupted.
3.5.2

Scheduled mode

In scheduled mode the DHW tank produces hot water corresponding
to a schedule. The best time to allow the tank to produce hot water is
at night, because the space heating demand is lower.
Example:
T t
1
2
60°C
50°C
40°C
15°C
00:00 07:00
T DHW tank temperature
t
t Time
▪ Initially, the DHW tank temperature is the same as the
temperature of the domestic water entering the DHW tank
(example: 15°C).
Operation manual
8
+
–
+
–
3
2 4
t
14:00 21:00
4
3
5
t
14:00 21:00
▪ At 00:00 the DHW tank is programmed to heat up the water to a
preset value (example: Comfort = 60°C).
▪ During the morning, you consume hot water and the DHW tank
temperature decreases.
▪ At 14:00 the DHW tank is programmed to heat up the water to a
preset value (example: Eco = 50°C). Hot water is available again.
▪ During the afternoon and evening, you consume hot water again
and the DHW tank temperature decreases again.
▪ At 00:00 the next day, the cycle repeats.
3.5.3

Scheduled + reheat mode

In scheduled + reheat mode, the domestic hot water control is the
same as in scheduled mode. However, when the DHW tank
temperature drops below a preset value (=reheat tank temperature –
hysteresis value; example: 35°C), the DHW tank heats up until it
reaches the reheat set point (example: 45°C). This ensures that a
minimum amount of hot water is available at all times.
Example:
T t
1
2
60°C
50°C
45°C
35°C
15°C
00:00 07:00
T DHW tank temperature
t
t Time
3.5.4

Using DHW powerful operation

About powerful operation
Powerful operation allows the domestic hot water to be heated by
the backup heater. Use this mode on days when there is more hot
water usage than usual.
To check if powerful operation is active
If is displayed on the home screen, powerful operation is active.
Activate or deactivate Powerful operation as follows:
1 Go to [5.1]: Tank > Powerful operation
2 Turn powerful operation Off or On.
Usage example: You immediately need more hot water
You are in the following situation:
▪ You already consumed most of your domestic hot water.
▪ You cannot wait for the next scheduled action to heat up the
domestic hot water tank.
Then you can activate powerful operation. The domestic hot water
tank will start heating up the water to the Comfort temperature.
INFORMATION
When powerful operation is active, the risk of space
heating/cooling and capacity shortage comfort problems is
significant. In case of frequent domestic hot water
operation, frequent and long space heating/cooling
interruptions will happen.
3.6

Advanced usage

The amount of information you can read out and edit in the menu
structure depends on your user permission level:
▪ User: Standard mode
3 4
5
t
14:00 21:00
EGSAH/X06+10(U)DA9W(G)
Daikin Altherma 3 GEO
4P569812-2B – 2019.10