PAW FriwaMega - DN 32 User manual

PAW GmbH & Co. KG
Böcklerstr. 11, D-31789 Hameln, Germany
Phone: [phone], Fax: [phone]
E-mail: [email protected], Web: www.paw.eu
2014/11 99640766x-mub-en – V03 1
Installation and Operation Instructions
Domestic Hot Water Module
FriwaMega – DN 32

1General Information
2 99640766x-mub-en – V03 2014/11
Item no. 99640766x-mub-en - Version V03 – Date 2014/11
Translation of the original instructions
We reserve the right to make technical changes without notice!
Printed in Germany – Copyright by PAW GmbH & Co. KG
PAW GmbH & Co.KG
Böcklerstraße 11
D-31789 Hameln, Germany

1General Information
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Contents
1General Information.........................................................................................................4
1.1 Scope of these instructions ..........................................................................................4
1.2About this product ........................................................................................................5
1.3 Designated use ............................................................................................................5
2Safety instructions ...........................................................................................................6
3Product description..........................................................................................................8
4Dimensioning and planning............................................................................................10
4.1 Dimensioning of the tank............................................................................................11
5Circulation mode ...........................................................................................................12
6Assembly and installation [specialist]..............................................................................13
7Commissioning [specialist].............................................................................................16
7.1 Filling the primary circuit.............................................................................................17
7.2 Commissioning of the controller .................................................................................18
7.3 Maximum withdrawal flow rate ...................................................................................20
7.4 Setting the temperature..............................................................................................22
8Maintenance [specialist].................................................................................................23
9Spare parts [specialist] ..................................................................................................24
9.1 Control and insulation.................................................................................................24
9.2 Hydraulics primary circuit (6407660, 6407661, 6407662)........................................... 25
9.3 Hydraulics secondary circuit FriwaMega without circulation (6407660) ...................... 26
9.4 Hydraulics secondary circuit FriwaMega with circulation (6407661, 6407662)............ 27
10 Technical data...............................................................................................................28
10.1 Pressure drop characteristics .....................................................................................29
11 Commissioning report....................................................................................................30

1General Information
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1General Information
1.1 Scope of these instructions
These instructions describe the installation, commissioning, function and operation of the
domestic hot water module FriwaMega.
The chapters called [specialist] are intended for specialists only.
For other components of the system, such as tanks, controllers or pumps, please observe
the instructions of the corresponding manufacturer.
Item
Item number
Controller
FC3.8
Pump
primary
Circulation
Heat
exchanger
FriwaMega
6407660
Grundfos
UPM XL 25-125
Optional:
Grundfos
UPM2 15-75 CIL2
or
Grundfos
UPML 25-105 N
2 x 60 plates
FriwaMega
with
circulation
6407661
Grundfos
UPM XL 25-125
Grundfos
UPML 25-105 N 2 x 60 plates
6407662
Grundfos
UPM XL 25-125
Grundfos
UPM2 15-75 CIL2 2 x 60 plates
Carefully read these instructions before installation and commissioning.
Save these instructions in the vicinity of the installation for future reference.

1General Information
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1.2 About this product
The domestic hot water module is a premounted fitting group checked for leakage and used
to transfer the heat between the buffer tank and the domestic hot water circuit.
It contains a preset controller and important fittings for the operation of the system:
•Ball valves in the primary circuit
•Piston valves in the secondary circuit
•Pressure relief valve in the secondary circuit
•Premounted controller
•Temperature sensor on the cold water inlet
•Temperature sensors on the heating flow
•Temperature sensor on the domestic hot water outlet
•Flow meter on the domestic hot water outlet
•Fill and drain valve for draining the heat exchangers in the primary and secondary circuit
•Vent valve, primary and secondary, for venting the heat exchangers
1.3 Designated use
The domestic hot water module must only be mounted in heating installations between
the buffer tank and the domestic hot water circuit.
Due to its design, the station must be mounted and operated in a vertical position!
The technical data specified in these instructions must be observed.
Only use PAW accessories with the domestic hot water module.
Improper usage excludes any liability claims.
The wrapping materials are made of recyclable materials and can be disposed of
with recyclable materials.

2Safety instructions
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2Safety instructions
The installation and commissioning as well as the connection of electrical components require
technical knowledge commensurate with a recognised vocational qualification as a fitter for
plumbing, heating and air conditioning technology, or a profession requiring a comparable level
of knowledge [specialist].
The following must be observed during installation and commissioning:
•relevant local and national regulations
•accident prevention regulations of the professional association
•instructions and safety instructions of this manual
WARNING
Danger of scalding due to hot water!
Undesirable circulation of water in the primary circuit can cause the exit of water
of up to 90 °C at the withdrawal point.
External pumps must not be installed between the service water module
and the buffer tank.
The domestic hot water module must not be connected to a distribution
manifold.
CAUTION
Risk of burns!
The valves, fittings and the pump may heat up to more than 95 °C during
operation.
The insulating shell must remain closed during operation.

2Safety instructions
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NOTICE
Material damage due to mineral oils!
Mineral oil products cause lasting damage to seals made of EPDM, whereby the sealant
properties get lost. We do not assume liability nor provide warranty for damage to property
resulting from sealants damaged in this way.
It is imperative to avoid that EPDM gets in contact with substances containing
mineral oils.
Use a lubricant based on silicone or polyalkylene and free of mineral oils, such as
Unisilikon L250L and Syntheso Glep 1 of the Klüber company or a silicone spray.
NOTICE
Malfunction!
The domestic hot water module must be integrated in the potential equalisation of the
electric installation. This can be guaranteed by establishing a potential equalisation
connection to the main potential connection according to regulations or by the connected
pipe system.

3Product description
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3Product description
Connections primary circuit
1
Flow from the buffer tank (warm)
2
Return to the buffer tank (cold)
Equipment primary circuit
A
Return ball valve
B
Check valve
C
Heat exchanger
D
Temperature sensor Pt1000
E
Drain valve
F
Primary pump
G
Check valve
H
Flow ball valve

3Product description
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Connections secondary circuit
3
Cold water supply
4
Hot water outlet
5
Hot water circulation
Equipment secondary circuit
a
Piston valve hot water circulation
b
Piston valve cold water inlet
c
Pressure relief valve 10 bars, suitable
for domestic hot water
Only for the protection of the station.
Does not replace the pressure relief
valve that has to be mounted on site!
d
Temperature sensor Pt1000
e
Heat exchanger
f + g
FlowSonic 1-130 l/min
h
Drain valve
i
Temperature sensor Pt1000
j
Circulation pump
k
Piston valve hot water outlet

4Dimensioning and planning
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4Dimensioning and planning
The FriwaMega is a domestic hot water module operating on the principle of a flow-type
water heater.
The FriwaMega will only work flawlessly if the installation meets certain requirements.
Please take some time to plan the installation.
WARNING
Danger of scalding due to hot water!
Undesirable circulation of water in the primary circuit can cause the exit of water
of up to 90 °C at the withdrawal point.
External pumps must not be installed between the service water module
and the buffer tank.
The domestic hot water module must not be connected to a distribution
manifold.
Mounting example
FriwaMega with optional circulation set (additionally required, item no. 6404134GH7
or 6404135GH10)

4Dimensioning and planning
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4.1 Dimensioning of the tank
The following table helps you to calculate the approximately required volume of the buffer tank.
Temperature in
the buffer tank
Domestic hot water temperature
set at the controller
Required tank volume
per litre of hot water
50 °C 45 °C 1.3 litres
60 °C
45 °C 0.8 litre
50 °C 1.0 litre
55 °C 1.4 litres
70 °C
45 °C 0.7 litre
50 °C 0.8 litre
55 °C 0,9 litre
80 °C
45 °C 0.5 litre
50 °C 0.6 litre
55 °C 0.7 litre
Calculation example for the dimensioning of the buffer tank:
Temperature buffer tank: 60 °C
Required withdrawal flow rate at the tap: 20 l/min
Domestic hot water temperature set at the controller: 45 °C
How large must the tank be to allow for a continuous withdrawal during 20 minutes
without reheating?
20 l/min x 20 min = 400 l
400 l x 0.8 = 320 l
The heated part of the buffer tank must have a volume of 320 litres.

5Circulation mode
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5Circulation mode
The domestic hot water module is optionally equipped with a circulation pump.
The FriwaMega without circulation can be subsequently equipped with a circulation set
(item no. 6404134GH7 or 6404135GH10) for an internal retrofitting.
Three different operating modes of the circulation pump are set at the controller
(see controller instructions, menu "Func" / "F02"):
•
Pulse-controlled operation
(depending on the demand / requirements):
The short opening of a hot water tap (tap pulse: ~2 sec.) starts the circulation pump.
The circulation pump will then run for several minutes (adjustable).
•
Time-dependent operation:
The operation of the circulation pump can be set on a week clock within a freely
selectable period of time. The circulation will start at the beginning of the period
of time chosen. The circulation will stop after the end of the chosen period of time.
•
Temperature-dependent operation:
In this operating mode, the circulation only starts if the adjustable minimum temperature
on the circulation temperature sensor is not reached during the chosen period of
operation. The circulation stops after the required temperature has been reached or
after the end of the chosen period of time.
The operating modes can be combined with one another as wished, f. ex. the time- and the
temperature-dependent operating modes. The circulation is only active if the temperature at the
circulation temperature sensor falls below the required value and if the time window is active.
Outside the time window, the circulation pump can be started by a tap pulse if the
pulse-controlled operation mode is additionally activated.
NOTICE
Damage to property!
When the Friwa is delivered, the circulation is not activated (see controller instructions, menu:
"Func" / "F02" set to "OFF"). Once the circulation line mounted, it is mandatory to select and
preset the operating mode. The revolution speed of the circulation pump must be determined
by the PWM signal (factory setting: 40 %).

6Assembly and installation [specialist]
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6Assembly and installation [specialist]
The domestic hot water module FriwaMega must only be connected with the storage tank by
separate connections for flow and return. External pumps must not be installed between the
domestic hot water module and the buffer tank. The circulation of water causes considerable
temperature fluctuations.
The domestic hot water connection must be carried out in accordance with the relevant norms
(for example DIN 1988)!
NOTICE
Damage to property!
The pressure relief valve integrated in the station does not replace the safety groups of the
potable water connection as per DIN 1988. The pressure relief valve only protects the module
from overpressures in case of servicing.
NOTICE
Damage to property!
If there are water supplies that may cause pressure surges (for example flush valves, washing
machines or dishwashers) connected to the same mains as the domestic hot water module,
we recommend the installation of water hammer arresters close to the place where these
pressure surges may be caused.
DHW
module
Fittings
Drain valve
Pressure relief valve
Return valve (non-return valve)
Evtl. pressure reducing valve
Test valve
Shut-off valve
Hot water
Cold water

6Assembly and installation [specialist]
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WARNING
Risk to life and limb due to electric shock!
Prior to commencing electrical work on the controller, pull the mains plug!
Only after completing all installation work, plug the mains plug of the
controller into a socket. Thus, an unintentional start of the motors is
avoided.
NOTICE
Damage to property!
The location of installation must be dry, load-carrying, frost-proof and protected against
ultraviolet radiation, in order to prevent material damage of the installation.
Top view
1. Determine the mounting location of the
domestic hot water module near the buffer
tank. In long pipes, the transmission
performance may be reduced due to higher
pressure losses.
2. Remove the station from the packaging.
3. Remove the station from the pallet and
position it at the location of installation.
4. Mount the enclosed stand feet in order to
compensate the unevenness of the floor.
5. The station can be mounted in a corner.
If you want to pull off the insulation shells,
you have to leave a space of about 20 cm
to the wall (see figure).
6. For the operation of the hydraulics and a
subsequent servicing, you have to leave a
space of at least 60 cm to the front (controller)
and to one side (see figure).

6Assembly and installation [specialist]
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7. Connect the domestic hot water module with the installation by using the pipes as shown
in the figure below. When the station is delivered, the ball valves and piston valves are
closed, in order to protect the station against dirt. Before connecting the pipes, make
sure that the connections are free from dirt.
1
Primary side: flow from the buffer tank (hot)
Connection: 1½" internal thread, flat sealing
Piping:
at least DN 40, 42 x 1,5 mm,
maximum length 4 m
Make sure to vent the Friwa at the highest point!
2
Primary side: return to the buffer tank (cold)
Connection: 1½" internal thread, flat sealing
Piping:
at least DN 40, 42 x 1,5 mm,
maximum length 4 m
Make sure to vent the Friwa at the highest point!
3
Secondary side: cold water inlet
Connection: 1½" external thread, flat sealing
4
Secondary side: hot water outlet
Connection: 1½" external thread, flat sealing
5
Secondary side:
Hot water circulation, return
Connection: 1½" external thread, flat sealing

7Commissioning [specialist]
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7Commissioning [specialist]
Note!
Slowly
open the valves in the pipes and in the module, in order to prevent pressure surges.
Function check valve
The ball valves (A) and (H) in the primary circuit are
equipped with check valves (B) and (G), in order to
avoid unwanted gravity circulation.
For venting and flushing the installation, the check
valves must be open. Turn the opening mechanism of
the check valves into the position
180°
. The check
valve is not operating.
For the operation of the installation, all (ball) valves
must be
completely
open and the check valves must
be closed again (position
0°
).
Check valve
(normal flow direction in the figure: downwards)
Position 0°
Check valve is operating,
flow only in direction of flow.
Position 180°
Check valve is not operating,
flow in both directions.

7Commissioning [specialist]
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7.1 Filling the primary circuit
WARNING
Danger of scalding due to hot water!
The system is under pressure. By opening the pressure relief valve, hot water
with a temperature of up to 90 °C may exit and cause personal injury.
Open the pressure relief valve slowly and with sufficient distance.
If the storage tank is (partly) filled
Primary circuit
1. Slowly open the ball valves (A) and (H).
2. Open the check valves (B) and (G) at the
opening mechanism (
180°
, see page 16).
3. Fill the storage tank using the already existing fill
valves until an operating pressure of about
1.5 bars* is reached.
Use appropriate water according to VDI 2035 /
ÖNorm H5195-1.
4. Vent the pipe system at the designated points
on site.
5. Check the operating pressure of the storage tank
after the venting and increase the pressure
if necessary.
6. Put the check valves (B) and (G) into operating
position (
0°
, see page 16).
* 1.5 bars in the primary circuit = recommended minimum value
The pressure also depends on the individual system pressures and on the components of
the heating installation!

7Commissioning [specialist]
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7.2 Commissioning of the controller
WARNING
Risk to life and limb due to electric shock!
Check if the sensors and the pumps are properly connected to the
controller and if the controller housing is closed.
Only under these circumstances, the mains plug of the controller can
be plugged into a socket.
1. Make sure that the integration of the
domestic hot water module in the potential
equalisation of the installation is correct.
2. Connect the domestic hot water module
to the mains (230 V, 50 Hz).
3. Remove the insulation and the front panel
of the controller (see controller manual,
page 5).
4. Select the manual operating mode ("H1")
in the selection menu of the controller.
Switch on the PWM signal of the pump
("100 %").
5. Let the pump run for several minutes to
deaerate the domestic hot water module.
6. If the air noises have stopped, the pump
can be switched off. For this purpose,
select the manual operating mode ("H1")
in the selection menu of the controller.
7. Set the pump to automatic operation ("A").

7Commissioning [specialist]
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Secondary circuit
8. Slowly open the piston valves (b) and (k)
on the secondary side.
9. Open at least one withdrawal point for
domestic hot water (for example a tap) with
a flow rate of at least 10 l/min and let the
water run for about 2 minutes to deaerate
the secondary circuit. Close all withdrawal
points in the secondary circuit afterwards.
10. Manipulate the pressure relief valve (c)
to deaerate the heat exchanger.
11. Check the module for tightness and make
sure that the electronic components stay
dry.
12. Set the desired domestic hot water
temperature at the controller (see page 22).
The domestic hot water module is now ready
for operation.

7Commissioning [specialist]
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7.3 Maximum withdrawal flow rate
The following diagram illustrates the maximum withdrawal flow rate depending on the tank
temperature with a preset hot water temperature of 45 °C at the tap. The integrated control
prevents the temperature from falling, as long as the maximum flow rate is not exceeded
and as long as the water in the buffer tank maintains a sufficient temperature.
Withdrawal flow rate [l/min]
Power [kW]
Boundary conditions:
Cold water temperature: 10 °C
Maximum pressure loss on the domestic hot water side of the Friwa:
1000 mbars
The following examples illustrate the correlation between the domestic hot water temperature,
the withdrawal flow rate and the temperature of the buffer tank and show their impact on the
heat transfer capacity of the Friwa.
Example 1
Domestic hot water temperature at the withdrawal point: 45 °C
Temperature in the buffer tank: 60 °C
FriwaMega: maximum withdrawal flow rate: 123 l/min, transfer capacity: 300 kW
Example 2
Domestic hot water temperature at the withdrawal point: 45 °C
Maximum withdrawal flow rate: 120 l/min
FriwaMega: temperature in the buffer tank: ~70 °C, transfer capacity: 290 kW
Domestic hot water temperature: 45 °C
Example 1
Temperature of the buffer tank
FriwaMega
Example 2