5 | Operation
User reference guide
32
EHVZ04+08S18+23EA
Daikin Altherma 3 R F
4P629094-1A – 2021.02
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 function is
regularly interrupted.
5.7.3 Scheduled mode
In scheduled mode the DHWtank 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
60°C
00:00 07:00
50°C
15°C
40°C
14:00 21:00
1
2
3
4
5
T
t
T
t
DHWtank temperature
t Time
▪ Initially, the DHW tank temperature is the same as the temperature of the
domestic water entering the DHWtank (example: 15°C).
▪ 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
DHWtank temperature decreases again.
▪ At 00:00 the next day, the cycle repeats.
5.7.4 Scheduled + reheat mode
In scheduled + reheat mode, the domestic hot water control is the same as in
scheduled mode. However, when the DHWtank temperature drops below a preset
value (=reheat tank temperature – hysteresis value; example: 35°C), the DHWtank
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
t
60°C
00:00 07:00
50°C
45°C
15°C
14:00 21:00
35°C
1
2
4
5
3
T
t
Domestic hot water tank temperature
t Time