Selecting The Volume And Desired Temperature For The Dhw Tank; Setup And Configuration - Dhw Tank; Dhw Pump For Instant Hot Water; Dhw Pump For Disinfection - Daikin Altherma ERLQ004-006-008CA Reference Manual

5 Application guidelines
5.3.2 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 desired temperature for the DHW tank consists of:
1 Determining the DHW consumption (equivalent hot water
volume at 40°C).
2 Determining the desired temperature for the 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 increase this
temperature. However, this consumes more energy. Daikin
recommends to set the desired DHW tank temperature below
55°C to avoid using the backup heater.
▪ 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
Installer reference guide
12
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
—
Determining the volume and desired temperature for the DHW
tank
Formula
V =V +V ×(T −40)/(40−T )
1 2 2 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
5.3.3 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
5.3.4

DHW pump for instant hot water

Setup
h
c
a
i
f
b
g
a Indoor unit
b DHW tank
c DHW pump (field supply)
f Shower (field supply)
g Cold water
h Domestic hot water OUT
i Recirculation connection
▪ By connecting a DHW pump, instant hot water can be available at
the tap.
▪ The DHW pump and the installation are field supply and the
responsibility of the installer.
▪ For more information about
connection: see "7 Installation" on
Configuration
▪ For more information, see "8 Configuration" on
▪ You can program a schedule to control the DHW pump via the
user interface. For more information, see the user reference
guide.
5.3.5

DHW pump for disinfection

Setup
h
c
a
i
d f
b
e g
a Indoor unit
b DHW tank
c DHW pump (field supply)
d Heater element (field supply)
e Non‑return valve (field supply)
f Shower (field supply)
g Cold water
h Domestic hot water OUT
Example
If:
▪ V =180 l
2
▪ T =54°C
2
▪ T =15°C
1
Then V =280 l
1
"8 Configuration" on page 38.
connecting the recirculation
page 22.
page 38.
ERLQ004~008CA + EHVZ04+08S18CB
Daikin Altherma – Low temperature split
4P401676-1 – 2015.02