Daikin ETVH16S18EA9W, User Reference Manual

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5 | Operation
User reference guide
32
ETVH/X16S(U)18+9W + ETBH/9W
Daikin Altherma 3 H HT F+W
4P644740-1 – 2021.02
INFORMATION
Risk of space heating capacity shortage for domestic hot water tank without internal
booster heater: In case of frequent domestic hot water operation, frequent and long
space heating/cooling interruption will happen when selecting the following:
Tank > Heat up mode > Reheat only .
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.
5.7.3 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
60°C
00:00 07:00
50°C
15°C
40°C
14:00 21:00
1
2
3
4
5
Tt
T
t
DHW tank temperature
t Time
▪ Initially, the DHW tank temperature is the same as the temperature of the
domestic water entering the DHW tank (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
DHW tank temperature decreases again.
▪ At 00:00 the next day, the cycle repeats.
5.7.4 Sch 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: