Setting Up The Domestic Hot Water Tank; System Layout - Integrated Dhw Tank; Selecting The Volume And Desired Temperature For The Dhw Tank; Setup And Configuration - Dhw Tank - Daikin Altherma ERLQ004CAV3 Installer's Reference Manual

5 Application guidelines
5.4
Setting up the domestic hot water
tank
5.4.1
System layout – Integrated DHW tank
UI
a b c d f h h
M
e
g
a
Outdoor unit
b
Indoor unit
c
Heat exchanger
d
Backup heater
e
Pump
f
Motorised 3­way valve
g
DHW tank
h
Shut­off valve
i
Collector (field supply)
FHL1...3
Under floor heating
UI
User interface
5.4.2
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
Type
Integrated DHW tank
Energy saving tips
▪ If the DHW consumption differs from day to day, you can program
a weekly schedule with different desired DHW tank temperatures
for each day.
▪ 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.
▪ 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.
Installer reference guide
16
i
FHL1
FHL2
FHL3
Possible volumes
180 l
▪ The higher the outdoor temperature, the better the performance of
the heat pump.
▪ If energy prices are the same during the day and the night,
Daikin recommends to heat up the DHW tank during the day.
▪ If energy prices are lower during the night, Daikin recommends
to heat up the DHW tank during the night.
▪ 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:
Question
How many showers are needed
per day?
How many baths are needed per
day?
How much water is needed at the
kitchen sink per day?
Are there any other domestic hot
water needs?
Example: If the DHW consumption of a family (4 persons) per day is
as follows:
▪ 3 showers
▪ 1 bath
▪ 3 sink volumes
Then the DHW consumption = (3×100 l)+(1×150 l)+(3×10 l)=480 l
Determining the volume and desired temperature for the DHW
tank
Formula
V =V +V ×(T −40)/(40−T )
1 2 2 2 1
V =V ×(40−T )/(T −T )
2 1 1 2 1
V DHW consumption (equivalent hot water volume at 40°C)
1
V Required DHW tank volume if only heated once
2
T DHW tank temperature
2
T Cold water temperature
1
5.4.3
Setup and configuration – DHW tank
▪ For large DHW consumptions, you can heat up the DHW tank
several times during the day.
▪ To heat up the DHW tank to the desired DHW tank temperature,
you can use the following energy sources:
▪ Thermodynamic cycle of the heat pump
▪ Electrical backup heater
▪ For more information about optimizing the energy consumption for
producing domestic hot water, see "8 Configuration" on page 41.
ERLQ004~008CA + EHVH04+08S18CA3VF
Typical water volume
1 shower = 10 min×10 l/min =
100 l
1 bath = 150 l
1 sink = 2 min×5 l/min = 10 l
—
Example
If:
▪ V =180 l
2
▪ T =54°C
2
▪ T =15°C
1
Then V =280 l
1
If:
▪ V =480 l
1
▪ T =54°C
2
▪ T =15°C
1
Then V =307 l
2
Daikin Altherma low temperature split
4P366226­1 – 2014.01