Rotex RHBH04CB3V, Руководство по установке для специалистов

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5 Application guidelines
Installer reference guide
18
RRLQ004~008CA + RHBH/X04+08CB
ROTEX HPSU low temperature Bi‑bloc
4P384979-1C – 2017.04
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
Depending on the available options, tanks with the following volumes
are available:
Type Possible volumes
Standalone DHW tank ▪ 150 l
▪ 200 l
▪ 300 l
▪ 500 l
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. ROTEX
recommends to set the desired DHW tank temperature below
55°C to avoid using the electrical resistance.
▪ 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,
ROTEX recommends to heat up the DHW tank during the day.
▪ If energy prices are lower during the night, ROTEX
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, ROTEX 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 Typical water volume
How many showers are needed
per day? 1 shower = 10 min×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×5 l/min = 10 l
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 Example
V
1
=V
2
+V
2
×(T
2
−40)/(40−T
1
) If:
▪ V
2
=180 l
▪ T
2
=54°C
▪ T
1
=15°C
Then V
1
=280 l
V
2
=V
1
×(40−T
1
)/(T
2
−T
1
) If:
▪ V
1
=480 l
▪ T
2
=54°C
▪ T
1
=15°C
Then V
2
=307 l
V
1
DHW consumption (equivalent hot water volume at 40°C)
V
2
Required DHW tank volume if only heated once
T
2
DHW tank temperature
T
1
Cold water temperature
5.4.4 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 integrated DHW tank)
▪ Electrical booster heater (for standalone DHW tank)
▪ For more information about:
▪ Optimizing the energy consumption for producing domestic hot
water, see "8 Configuration" on page 45 .
▪ Connecting the electrical wiring of the standalone DHW tank to
the indoor unit, see the installation manual of the DHW tank.
▪ Connecting the water piping of the standalone DHW tank to the
indoor unit, see the installation manual of the DHW tank.
5.4.5 DHW pump for instant hot water
Setup
c
f
a
b
g
h
i
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 connecting the recirculation
connection:
▪ for integrated DHW tank, see "7 Installation" on page 29 ,
▪ for separate DHW tank, see installation manual of DHW tank.
Configuration
▪ For more information, see "8 Configuration" on page 45 .