Installer reference guide
15
08 + ERLQ004~008
Daikin Altherma - Low Temperature Split
4P313774-1 – 2012.05
5 Application guidelines
5.4
Setting up the domestic hot water tank
The DHW tank can be:
Q
Integrated in the indoor unit
Q
Installed standalone as option
5.4.1 System layout – Integrated DHW tank
5.4.2 System layout – Standalone DHW tank
5.4.3 Selecting the volume and desired
temperature for the DHW tank
People experience water as hot when its temperature is 40°C.
Therefore, the DHW consumption is always expressed as equivalent
hot water volume at 40°C. However, you can set the DHW tank
temperature at a higher temperature (example: 53°C), which is then
mixed with cold water (example: 15°C).
Selecting the volume and desired temperature for the DHW tank
consists of:
1
Determining the DHW consumption (equivalent hot water
volume at 40°C).
2
Determining the volume and desired temperature for the DHW
tank.
Possible DHW tank volumes
Energy saving tips
Q
If the DHW consumption differs from day to day, you can
program a weekly schedule with different desired DHW tank
temperatures for each day.
Q
The lower the desired DHW tank temperature, the more cost
effective. By selecting a larger DHW tank, you can lower the
desired DHW tank temperature.
Q
The heat pump itself can produce domestic hot water of
maximum 55°C (50°C if outdoor temperature is low). The
electrical resistance integrated in the heat pump can higher this
temperature. However, this consumes more energy. Daikin
recommends to set the desired DHW tank temperature below
55°C to avoid using the electrical resistance.
Q
The higher the outdoor temperature, the better the performance
of the heat pump.
Q
If energy prices are the same during the day and the night,
Daikin recommends to heat up the DHW tank during the
day.
Q
If energy prices are lower during the night, Daikin
recommends to heat up the DHW tank during the night.
Q
When the heat pump produces domestic hot water, it cannot
heat up a space. When you need domestic hot water and space
heating at the same, Daikin recommends to produce the
domestic hot water during the night when there is lower space
heating demand.
Determining the DHW consumption
Answer the following questions and calculate the DHW consumption
(equivalent hot water volume at 40°C) using the typical water
volumes:
Example: If the DHW consumption of a family (4 persons) per day is
as follows:
Q
3 showers
Q
1 bath
Q
3 sink volumes
Then the DHW consumption = (3x100 l) + (1x150 l) + (3x10 l) = 480 l
a
Outdoor unit
b
Indoor unit
c
Heat exchanger
d
Backup heater
e
Pump
f
Motorised 3-way valve
g
DHW tank
h
Shut-off valve
i
Collector (field supply)
FHL1...3
Under floor heating
UI
User interface
a
Outdoor unit
b
Indoor unit
c
Heat exchanger
d
Backup heater
e
Pump
f
Shut-off valve
g
Motorised 3-way valve
h
Collector (field supply)
i
DHW tank
j
Heat exchanger coil
FHL1...3
Under floor heating
FHL1
FHL2
FHL3
M
UI
a
b c
d
h
h
i
f
e
g
FHL1
FHL2
FHL3
M
a
b c
d
e
h
f
g
f
i
j
Type
Possible volumes
Integrated DHW tank
Q
180 l
Q
260 l
Standalone DHW tank
Q
150 l
Q
200 l
Q
300 l
Question
Typical water volume
How many showers are needed
per day?
1 shower = 10 min x 10 l/min =
100 l
How many baths are needed per
day?
1 bath = 150 l
How much water is needed at the
kitchen sink per day?
1 sink = 2 min x 5 l/min = 10 l
Are there any other domestic hot
water needs?
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