REMKO EFS Series User manual

Operating and
installation instructions
Read the instructions prior to performing any task!
REMKO EFS series
EFS 21
Fresh water station
0321-2022-11 Edition 1, en_GB
Instructions for users and specialists

Translation of the original
Read these operating instructions carefully before commis-
sioning / using this device!
These instructions are an integral part of the system and must
always be kept near or on the device.
Subject to modifications; No liability accepted for errors or mis-
prints!

Table of contents
1 Safety and usage instructions............................................................................................................. 4
1.1 General safety notes....................................................................................................................... 4
1.2 Identification of notes...................................................................................................................... 4
1.3 Personnel qualifications.................................................................................................................. 4
1.4 Dangers of failure to observe the safety notes................................................................................ 4
1.5 Safety-conscious working............................................................................................................... 4
1.6 Safety instructions for the operator................................................................................................. 5
1.7 Safety notes for installation and inspection tasks........................................................................... 5
1.8 Unauthorised modification and changes......................................................................................... 5
1.9 Intended use................................................................................................................................... 6
1.10 Safety-conscious working............................................................................................................. 6
1.11 Warranty........................................................................................................................................ 6
1.12 Transportation and packaging....................................................................................................... 6
1.13 Environmental protection and recycling........................................................................................ 6
2 Technical data........................................................................................................................................ 7
2.1 Unit data.......................................................................................................................................... 7
2.2 Unit dimensions and space requirements....................................................................................... 8
2.3 Pump data....................................................................................................................................... 8
3 Design and planning........................................................................................................................... 10
3.1 General notes................................................................................................................................ 10
3.2 Design of the storage tank............................................................................................................ 11
3.3 Setting the Temperature................................................................................................................ 12
3.4 Corrosion protection...................................................................................................................... 13
3.5 Calcification protection.................................................................................................................. 14
4 Assembly............................................................................................................................................. 15
5 Hydraulic connection.......................................................................................................................... 16
6 Electrical wiring................................................................................................................................... 17
7 Commissioning (specialist)............................................................................................................... 18
7.1 Leak test and filling of the system................................................................................................. 18
7.2 Initial commissioning..................................................................................................................... 18
7.3 Gravity brake................................................................................................................................. 18
7.4 Maximum dispensing medium flow rate........................................................................................ 19
7.5 Circulation operation..................................................................................................................... 21
7.6 Commissioning report................................................................................................................... 22
8 Shutdown............................................................................................................................................. 22
9 Troubleshooting and customer service ........................................................................................... 23
10 Care and maintenance........................................................................................................................ 24
11 View of the unit and spare parts........................................................................................................ 25
12 Index..................................................................................................................................................... 26
3

1 Safety and
usage instructions
1.1 General safety notes
Carefully read the operating manual before com-
missioning the units for the first time. It contains
useful tips and notes such as hazard warnings to
prevent personal injury and material damage.
Failure to follow the directions in this manual not
only presents a danger to people, the environment
and the system itself, but will void any claims for
liability.
Keep this operating manual and the refrigerant
data sheet near to the units.
1.2 Identification of notes
This section provides an overview of all important
safety aspects for proper protection of people and
safe and fault-free operation.The instructions and
safety notes contained within this manual must be
observed in order to prevent accidents, personal
injury and material damage.
Notes attached directly to the units must be
observed in their entirety and be kept in a fully
legible condition.
Safety notes in this manual are indicated by sym-
bols. Safety notes are introduced with signal words
which help to highlight the magnitude of the danger
in question.
DANGER!
Contact with live parts poses an immediate
danger of death due to electric shock. Damage
to the insulation or individual components may
pose a danger of death.
DANGER!
This combination of symbol and signal word
warns of a situation in which there is immediate
danger, which if not avoided may be fatal or
cause serious injury.
WARNING!
This combination of symbol and signal word
warns of a potentially hazardous situation,
which if not avoided may be fatal or cause
serious injury.
CAUTION!
This combination of symbol and signal word
warns of a potentially hazardous situation,
which if not avoided may cause injury or mate-
rial and environmental damage.
NOTICE!
This combination of symbol and signal word
warns of a potentially hazardous situation,
which if not avoided may cause material and
environmental damage.
This symbol highlights useful tips and recom-
mendations as well as information for efficient
and fault-free operation.
1.3 Personnel qualifications
Personnel responsible for commissioning, opera-
tion, maintenance, inspection and installation must
be able to demonstrate that they hold a qualifica-
tion which proves their ability to undertake the
work.
1.4 Dangers of failure to observe
the safety notes
Failure to observe the safety notes may pose a risk
to people, the environment and the units. Failure to
observe the safety notes may void any claims for
damages.
In particular, failure to observe the safety notes
may pose the following risks:
nThe failure of important unit functions.
nThe failure of prescribed methods of mainte-
nance and repair.
nDanger to people on account of electrical and
mechanical effects.
1.5 Safety-conscious working
The safety notes contained in this manual, the
existing national regulations concerning accident
prevention as well as any internal company
working, operating and safety regulations must be
observed.
REMKO EFS series
4

1.6 Safety instructions
for the operator
The operational safety of the units and compo-
nents is only assured providing they are used as
intended and in a fully assembled state.
nThe units and components may only be set up,
installed and maintained by qualified per-
sonnel.
nThe existing regulations concerning accident
prevention must be adhered to.
nDo not operate units or components with
obvious defects or signs of damage.
nContact with equipment parts or components
can lead to burns or injury.
nEnsure that electrical energy does not pose a
risk.
nRegulations of the VDE and the local energy
supply company must be adhered to.
NOTICE!
Material damage due to mineral oils!
Mineral oil products permanently damage
EPDM seal elements; the sealing properties
may therefore be lost. We do not take responsi-
bility or provide warranty replacements for
damage caused by seals that are damaged in
this way.
–It is essential that you prevent EPDM from
coming into contact with mineral oil sub-
stances.
–Use a lubricant that is free of mineral oil and
has a silicone or polyalkylene basis, such
as Unisilkon L250L and Syntheso Glep 1
made by Klüber, or a silicon spray.
1.7 Safety notes for installation and
inspection tasks
nThe operator must ensure that all inspection
and installation work is carried out by author-
ised and qualified personnel who have thor-
oughly read the operating manual.
nWorks on the pump/system may only be car-
ried out whilst at a standstill as a matter of prin-
ciple.
nAppropriate hazard prevention measures must
be taken to prevent risks to people when per-
forming installation, repair, maintenance or
cleaning work on the units.
nThe setup, connection and operation of the
units and its components must be undertaken
in accordance with the usage and operating
conditions stipulated in this manual and comply
with all applicable regional regulations.
nRegional regulations and laws as well as the
Water Ecology Act must be observed.
nThe power supply should be adapted to the
requirements of the units.
nThe units and components must be kept at an
adequate distance from flammable, explosive,
combustible, abrasive and dirty areas or
atmospheres.
nSafety devices may not be modified or
bypassed.
NOTICE!
Malfunction!
The fresh water module must be integrated into
the equipotential bonding system of the elec-
trical installation. If this is not ensured by the
pipe network, set up an approved potential
equalisation connection to the main potential
connection.
1.8 Unauthorised modification and
changes
The operational safety of the fresh water module
that was delivered is guaranteed only with
intended use in accordance with section 1.8 of the
operating instructions. Under no circumstances
should the threshold values specified in the data-
sheet be exceeded.
Modifications or changes to units and components
are not permitted and may cause malfunctions.
Safety devices may not be modified or bypassed.
Original replacement parts and accessories
authorised by the manufacturer ensure safety. The
use of other parts may invalidate liability for
resulting consequences.
5

1.9 Intended use
The fresh water module is only permitted to be
installed in heating systems between the buffer
tank and the domestic water circuit. Depending on
the design, it may only be installed and operated
vertically!
Use only REMKO accessories in conjunction with
the fresh water module.
Any different or additional use is a non-intended
use. The manufacturer/supplier assumes no lia-
bility for damages arising from a non-intended use.
The user bears the sole risk in such cases.
Intended use also includes working in accordance
with the operating and installation instructions and
complying with the maintenance requirements.
The threshold values specified in the technical
data must not be exceeded.
1.10 Safety-conscious working
The safety notes contained in this manual, the
existing national regulations concerning accident
prevention as well as any internal company
working, operating and safety regulations must be
observed.
1.11 Warranty
For warranty claims to be considered, it is essential
that the ordering party or its representative com-
plete and return the "certificate of warranty" to
REMKO GmbH & Co. KG at the time when the
units are purchased and commissioned.
The warranty conditions are detailed in the "Gen-
eral business and delivery conditions". Further-
more, only the parties to a contract can conclude
special agreements beyond these conditions. In
this case, contact your contractual partner in the
first instance.
1.12 Transportation and
packaging
The units are shipped in sturdy transport pack-
aging or within the heat pump housing. Immedi-
ately check the units on delivery and make a note
of any damage or missing parts on the delivery
note. Inform the forwarding agent and contractual
partner. Claims under guarantee made at a later
date will not be accepted.
WARNING!
Plastic films and bags etc. are dangerous
toys for children!
Why:
- Leave packaging material are not around.
- Packaging material may not be accessible to
children!
1.13 Environmental protection and
recycling
Disposing of packaging
All products are packed for transport in environ-
mentally friendly materials. Make a valuable contri-
bution to reducing waste and sustaining raw mate-
rials. Only dispose of packaging at approved
collection points.
Disposing of the units and their components
For the manufacture of the units and components,
only recyclable materials have been used. Help
protect the environment by ensuring that the units
or components (for example batteries) are not dis-
posed of in household waste, but only in accord-
ance with local regulations and in an environmen-
tally safe manner, e.g. using authorised disposal
and recycling specialists or council collection
points.
REMKO EFS series
6

2 Technical data
2.1 Unit data
Series EFS 21
Nominal power at 10-45/65°C (KW-WW/HVL) kW 100
Tap capacity at nominal power l/min 41
Min. switch-on flow rate for primary pump l/min 2.0
NL count at nominal power 9.5
Power at 10-60/75°C (KW-WW/HVL) kW 104/194/291/388
Tap capacity at 10-60/75°C (incl. cascades) l/min 30/56/84/112
Capacity at 10-60/75°C, mixed to 45°C DHW kW 104
Tap capacity at 10-60/75°C, mixed to 45°C DHW (incl. cas-
cades) l/min 43/80/120/160
NL count at 10-60/75°C (incl. cascades) 10/32/62/96
Max. operating pressure for heating side bar 3
Max. operating pressure for service water side bar 10
Max. operating temperature for heating side °C 95
Max. operating temperature for service water side °C 65
Connections, heating side Inches 3/4" IG
Connections, service water side Inches 3/4" IG / 1" AG
Pressure loss, service water side at nominal power bar
0.67
Max. pressure loss for heating side piping mbar 50
Wilo PARA circulation pump power consumption W 3-45
Medium flow rate probe Huba probe type 235 2-40 l/min
Electrical wiring (mains regulation) V/Hz 230 V AC/50-60 Hz
Housing / Connecting parts
Housing / connecting parts
CW617N (2.0402) CW617N
(2.0402)
Plate heat exchanger Cu, soldered
Seals AFM
Insulation EPP foam 0.038 W/mK
We reserve the right to make technical changes for the purpose of technical advancement.
7

2.2 Unit dimensions and space requirements
Fig. 1: Unit dimensions
2.3 Pump data
Pressure loss characteristic curve
A
B
Fig. 2: Pressure loss characteristic curve
A: Wilo PARA 15/7 B: EFS 21
Specified pressure loss valid for heating (primary) and drinking water side (secondary).
REMKO EFS series
8

PWM logic (PWM 2)
Fig. 3: PWM logic
< 7 % Pump off
7-12 % Min. performance (operation)
12-15 % Min. performance (start-up)
15-95 % Proportional performance range
> 95 % Max. power
We reserve the right to make technical changes for the purpose of technical advancement.
9

3 Design and planning
3.1 General notes
The fresh water station is a fresh water module
that heats domestic water according to the contin-
uous flow heater principle. In order to ensure fault-
free operation of the fresh water station, the
system must fulfil certain prerequisites. Before
installation, take some time for planning.
NOTICE!
Storage tank mounting is only possible with
mounting templates (accessories).
CAUTION!
Danger of scalding due to hot water!
Due to external circulation in the primary circuit,
water with a temperature of up to 90 °C can
leak out at the dispensing connection.
–No external pumps are permitted to be
installed between the fresh water module
and the buffer tank.
–The fresh water module is not permitted to
be connected to a heating cycle distributor.
Installation example
This hydraulic diagram serves merely to assist in planning activities;
the hydraulic system on site must be planned and laid out by the installer!
Subject to technical changes!
A
A
1
B
2 3 4 5
Fig. 4: Fresh water station with optional circulation set and optional return distribution
A: Fresh water station
B: REMKO MPS storage tank
1: Cold water
2: Hot water
3: Unmixed heating cycle
4: Mixed heating cycle 1
5: Mixed heating cycle 2
REMKO EFS series
10

3.2 Design of the storage tank
You can use the following table to calculate the approximate required volume of the buffer tank.
Temperature in buffer tank [°C] HW temperature [°C] set on
controller
Reqd. Storage tank volume per
litre of HW [Litre]
50 45 1.9
60
45 1.1
50 1.5
55 2.1
70
50 1.0
55 1.2
60 1.6
80
50 0.8
55 0.9
60 1.1
Sample calculation for the design of the buffer tank:
Temperature of buffer tank: 60 °C, required dispensing medium flow rate at water valve: 20 l/min
DHW temperature set on the controller: 45 °C
How large must the Storage tank be if a 20-minute dispensing operation is to take place without reheating?
20 l/min x 20 min = 400 l
400 l x 1.1 = 440 l ð The heated part of the buffer tank must be 440 litres in size.
The hot water volume depends on the position of the installed S 08 probe (Smart Control hot water
probe). The higher this is installed on the buffer tank, the lower the hot water volume.
11

3.3 Setting the Temperature
Set the required (maximum) domestic hot water temperature on the controller under "Main menu / hot water /
target temperature".
To ensure that scalding cannot occur at the water valve, the maximum hot water temperature must not
exceed 60 °C.
Primary side
The temperature required in the buffer tank on the primary side depends on the desired hot water tempera-
ture and the required dispensing quantity. The temperature in the buffer tank must be at least 5 K above the
required hot water temperature.
Secondary side
The possible dispensing medium flow rate [l/min] on the water valve depends on the hot water temperature
that is set in the controller and the temperature that is available in the storage tank.
The recommended maximum domestic water medium flow rate through the fresh water module is ~42 l/min.
The following table shows the relationship between the storage tank temperature and the maximum dis-
pensing medium flow rate that is connected when the temperature on the valve is 45°C (e.g. single-lever
mixer). If the hot water temperature that is set on the Controller is higher than 45 °C, the dispensing medium
flow rate consists of a mixture of hot and cold water.
The transmission capacity that is specified for this is required to warm the water quantity of the dispensing
medium flow rate [l/min] from 10 °C to 45 °C.
Temperature in
buffer tank probe
S08
[°C]
HW temperature
set on the con-
troller
[°C]
Maximum medium
flow rate from the
fresh water sta-
tion with the set.
HW temperature
[l/min]
Maximum dis-
pensing medium
flow rate at the
water valve for an
HW Temperature
of 45 °C
[l/min]
Transmission
capacity of the
fresh water sta-
tion
[kW]
50 45 16 16 40
60
45 28 28 69
50 22 24 60
55 15 19 48
70
45 38 38 93
50 31 35 87
55 25 32 79
60 20 28 69
80
45 42* 42 102
50 40* 45 111
55 33 42 105
60 28 39 98
Reheating is not considered if the cold water tem-
perature is 10 °C
* maximum medium flow rate: 42 l/min, pressure
loss of the fresh water station is 1000 mbar in this
case (higher values are only possible to a limited
extent due to hydraulics. Measurement limit of the
medium flow rate probe ~ 42 l/min)
REMKO EFS series
12

3.4 Corrosion protection
To prevent corrosion damage to the plate heat exchanger, the following drinking water values must be
observed:
Copper soldered
Chloride 1) (CL-)
< 250 mg/l at 50°C
< 100 mg/l at 75°C
< 10 mg/l at 90°C
Sulphate 1) (SO42-)< 100 mg/l
Nitrate (NO3-)< 100 mg/l
pH value 7.5-9.0
Electrical conductivity (at 20°C) 10-500 µS/cm
Hydrogencarbonate (HCO3-)70-300 mg/l
Ratio HCO3- / SO42- > 1
Ammonium (NH4+)< 2 mg/l
Free chlorine gas < 0.5 mg/l
Sulphite < 1 mg/l
Ammonium < 2 mg/l
Hydrogen sulphide (H2S) < 0.05 mg/l
Free (aggressive) carbonic acid (CO2)< 5 mg/l
Iron (Fe) < 0.2 mg/l
Saturation index SI -0.2 < 0 < 0.2
Manganese (Mn) < 0.05 mg/l
Total hardness 4-14 [Ca2+;Mg2+]/[HCO3] < 0.5
Total org. carbon (TOC) < 30 mg/l
1) If the limit values for copper-soldered plate heat exchangers are exceeded, a full stainless steel plate heat
exchanger must be used.
We reserve the right to make technical changes for the purpose of technical advancement.
To prevent pitting corrosion in the installation, no new galvanised ferrous materials should be installed down-
stream of the copper-soldered plate heat exchanger in the hot water pipe without forming a protective layer.
For mixed installations with galvanised ferrous materials, the use of full stainless steel plate heat exchangers
(available on request) is required.
13

3.5 Calcification protection
The precipitation of chalk from the water increases massively at hot water temperatures above 55°C and a
water hardness above 8.5°dH. For this reason, the hot water target temperature should be set as low as pos-
sible while observing drinking water hygiene and, if necessary, the calcification should be reduced by using a
softening or other suitable limescale treatment system.
In heating systems in which the heating water inlet temperature would frequently be above 65°C due to the
system, thermal pre-mixing to 65°C makes sense. This applies above all to biomass systems, but also to
solar thermal systems. Conversely, pre-mixing can be dispensed with for heat pump heating systems with a
relatively low inlet temperature anyway, which means that a higher bulk output can be achieved. Refer to the
Maintenance chapter for recommendations on cleaning.
Water treatment measures to prevent calcification
Fresh hot water station with 50°C hot water outlet temperature
and
calcium carbonate mass concentration Inlet < 65°C Inlet > 65°C
< 1.5 mmol/l (< 150 mg/l)
< 8.4°dH None None
1.5-2.5 mmol/l (150-250 mg/l)
8.4-14°dH None Recommended
> 2.5 mmol/l (> 250 mg/l)
> 14°dH Recommended Required
REMKO EFS series
14

4 Assembly
General notes
NOTICE!
To avoid damage to the system, the installation
location must be dry, capable of carrying the
load and frost-free.
Wall installation
Proceed as follows for wall mounting:
nMark and drill two Ø 10 mm holes as shown in
the illustration below
nPlace expansion anchors
nScrew in the upper screw with washer until the
screw head is approx. 1 cm away from the wall
nHang the station in place
nAlign it horizontally and fix with second screw
and washer. Tighten both screws evenly
Fig. 5: Wall installation
Storage tank mounting
The fresh water station can be installed directly
with a REMKO storage tank charging unit or return
stratification kit on a REMKO storage tank. The kit
includes a mounting template to assist with
mounting the fresh water station directly on the
storage tank.
Please refer to the separate installation instruc-
tions for the individual installation kits.
Integration in a domestic connection group
(safety assembly)
Please note!
A domestic connection group (safety assembly)
is required despite an integrated safety valve
(DIN 1988)!
Installation example
A
Fig. 6: Installation example
A: Fresh water station
1: Shut-off valve
2: Pressure reducer
3: Test device
4: Check valve
5: Connection point for measuring device
6: Shut-off valve
7: Safety valve with drainage line and funnel trap
8: Through-flow membrane expansion vessel
(recommended if pressure fluctuations are
anticipated on the domestic connection side)
15

5 Hydraulic connection
The illustration below is an example representation with optional accessories (circulation unit). Other avail-
able accessories: Cold water connection kit and piping kit.
This illustration makes no claim to being complete and is no substitute for professional planning.
ZI
S3
Fig. 7: Hydraulic connection
HRL: Heating return
HVL: Heating supply flow
KW: Cold water
WW: Hot water
ZI: Circulation
S3: Probe
Optional circulation kit
The circulation kit with Wilo Yonos Para Z 15/7.0
130 RKC and PT1000 temperature probe is an
optional accessory for the EFS 21. It consists of
the circulation pump, 2 shut-off ball valves with a
backflow preventer and an immersion sleeve with
Pt1000 probe. A temperature probe is always
required for all circulation methods.
Dimensions and minimum space requirements for
assembly and maintenance work.
For further information, please refer to the sepa-
rate instructions for the circulation kit.
1
A
Fig. 8: Optional circulation kit
A: Flow direction
1: Sensor sleeve
REMKO EFS series
16

6 Electrical wiring
General notes
Work on the electrical system and the opening of
electrical enclosures may only be carried out in a
de-energised state and only by authorised spe-
cialist personnel. Ensure correct terminal assign-
ment and polarity for the connections. Protect the
controller and the electrical components from over-
voltage.
DANGER!
All electrical installation work is to be performed
by specialist companies. Disconnect the power
supply when connecting the electrical terminals.
The fresh water station is completely pre-assem-
bled and pre-wired at the factory. Connect the
mains cable for commissioning. For further details,
please refer to the separate controller instructions.
Circulation pump
The pump is controlled exclusively via the external
PWM signal. The green flashing LED display
shows that the unit is ready for operation (stand-
by). A steady green light indicates pump operation
at a speed corresponding to the PWM signal. A red
LED signals an error.
Fig. 9: Electrical wiring, pump
L: Brown
N: Blue
PE: Green/yellow
17

7 Commissioning (specialist)
7.1 Leak test and filling of the
system
A prerequisite for commissioning is the complete
installation of all hydraulic and electrical compo-
nents.
Check all components of the system, including all
elements and stations pre-assembled at the fac-
tory, for leaks and seal them accordingly in the
event of any leaks. Adjust the test pressure and
the test duration to the respective piping system
and the respective operating pressure.
Fill the drinking water side only with clean drinking
water in accordance with DIN 1988 and press the
air out of the pipes with a slight increase in pres-
sure.
NOTICE!
Avoid tap volume flows > 56 l/min, as these can
lead to the destruction of the probe in the long
term.
Fill the heating system incl. the primary side of the
fresh water system only with water that has been
filtered and treated per VDI 2035 if necessary, and
completely bleed the system.
7.2 Initial commissioning
Please observe the corresponding controller instructions for this.
Work step Procedure OK
Preparation and checks
nVisual check of the installation.
nAre all probes installed and connected in the right place?
nAre all outputs connected?
o
Switch on controller nSupply the controller with electrical power. o
Adjust controller
Please follow the instructions for the controller.
nSet the fresh water temperature (hot water temperature).
nSet circulation (optional).
nSet return stratification (optional)
nConfigure cascades (optional)
More settings nSet premix valve (optional)
Test outputs Activate all outputs one after the other and check whether the
pumps switch correctly. o
Check function
nCheck hot water preparation function.
nCheck the function of the circulation (optional).
nCheck return stratification function (optional)
nCheck cascade function (optional)
o
o
7.3 Gravity brake
To prevent incorrect circulation, a gravity brake is
installed in the heating return line. (see Fig.)
When commissioning, the heat exchanger must be
bled using the manual bleeder.
REMKO EFS series
18

7.4 Maximum dispensing medium flow rate
The following diagram shows the maximum dispensing medium flow rate depending on the storage tank
temperature; this assumes a pre-set hot water temperature of 45 °C at the dispensing connection. The
integrated regulation prevents the temperature from decreasing as long as the maximum medium flow rate is
not exceeded.
EFS
A
B
C
1
2
Fig. 10: Maximum dispensing medium flow rate
A: Dispensing medium flow rate [l/min]
B: Buffer storage temperature
C: Power [kW]
1: Example 1
2: Example 2
Boundary conditions:
Cold water temperature: 10 °C,
Maximum pressure loss on the domestic water
side of the fresh water station: 1000 mbar
The following examples explain the relationships
between the individual variables of the hot water
temperature, the dispensing medium flow rate and
the buffer tank temperature, and show how these
affect the transmission capacity of the fresh water
station.
The hot water temperature that is set in the
Smart Control controller (S 08 probe) is the ref-
erence temperature for the buffer tank. Factory
setting: 45 °C.
Example 1
Hot water temperature at the dispensing connec-
tion: 45 °C
Temperature in the buffer tank: 50 °C
ð Maximum dispensing medium flow rate: 16 l/
min, transmission capacity: 40 kW
Example 2
Hot water temperature at the dispensing connec-
tion: 45 °C
Maximum dispensing medium flow rate: 28 l/min
ð Temperature in the buffer tank: 60 °C, transmis-
sion capacity: 69 kW
19

The following diagram shows the maximum dispensing medium flow rate if the hot water temperature is 45°C
at the dispensing connection, after being mixed with cold water with a temperature of 10°C. The hot water
temperature set on the controller is 60°C.
EFS
A
B
C
1
2
Fig. 11: Maximum dispensing medium flow rate
A: Dispensing medium flow rate [l/min]
B: Buffer storage temperature
C: Power [kW]
1: Example 1
2: Example 2
Boundary conditions:
Cold water temperature: 10 °C,
Example 1
Hot water temperature on the controller: 60 °C
Temperature in the buffer tank: 70 °C
ð Maximum dispensing medium flow rate: 28 l/
min, transmission capacity: 69 kW
Example 2
Hot water temperature on the controller: 60 °C
Maximum dispensing medium flow rate: 21 l/min
ð Temperature in the buffer tank: ~65 °C, trans-
mission capacity: 52 kW
REMKO EFS series
20