Flexit Nordic S3 User manual

INSTALLATION INSTRUCTIONS
Air handling unit
INSTALLATION
INSTRUCTIONS
Nordic S3
ART.NO. 800120, 800121, 800122, 800123
115699EN-06
2023-05
Flexit
GO

2
NORDIC S3

3
NORDIC S3
Contents
1. Planning and preparation work.......................................................................................6
1.1. Joiner/Fitter............................................................................................................................6
1.2. Plumber .................................................................................................................................6
1.3. Electrician ..............................................................................................................................6
2. Installation .........................................................................................................................8
2.1. Positioning requirements ..................................................................................................9
2.2. Space requirements..........................................................................................................10
2.3. What is supplied?...............................................................................................................11
2.4. Installation ...........................................................................................................................12
3. Duct connection ..............................................................................................................14
3.1. Connection to the unit .....................................................................................................14
4. Electrical work..................................................................................................................15
4.1. For use with a water battery ...........................................................................................15
5. Plumbing work.................................................................................................................15
6. Cover.................................................................................................................................16
6.1. Preparations .......................................................................................................................16
6.2. Flexit duct cover.................................................................................................................16
7. Installing and adjusting the kitchen fan .......................................................................17
7.1. Installation ...........................................................................................................................17
7.1.1. Kitchen fan without motor ...............................................................................17
7.1.2. Kitchen fan with motor .....................................................................................17
7.2. Adjusting ..............................................................................................................................17
7.2.1. Kitchen fan without motor ...............................................................................17
7.2.2. Kitchen fan with motor ....................................................................................17
8. System and general drawings .......................................................................................18
8.1. System drawing (electric heating battery) ...................................................................18
8.2. System drawing (without heater)...................................................................................18
8.3. General drawing.................................................................................................................19
8.4. Nipple location ...................................................................................................................21
9. Technical data S3.............................................................................................................22
10. Dimensioned drawing S3 ...............................................................................................23
11. Capacity and sound data S3 ..........................................................................................24
12. Final checks/Starting.......................................................................................................25
12.1. Final checks .........................................................................................................................25
12.2. Startup and connection of the unit...............................................................................26
13. Complaints .......................................................................................................................27
14. Waste handling................................................................................................................27

4
NORDIC S3
DANGER! DO NOT
TOUCH
Symbols used
These products bear a number of symbols used for
labelling the actual product and in installation and user
documentation.
Extract air Extract air
from kitchen
Outdoor air
Supply air
Exhaust air
DANGER:
ELECTRICITY
INFO! When a text box is this
FRORXULWbPHDQVWKDWLWFRQWDLQV
important information.
i
CAUTION! When a text box is this
colour, it means that material
damage may be the consequence
of not following the instructions.
!
DANGER! When a text box is
this colour, it means that a life-
threatening or serious personal
injury may be the consequence of
not following the instructions.
!
NOTICE! When a text box is this
colour, it means that a poor
utilisation ratio or product
operating issues may be the
consequence of not following the
instructions.
EXAMPLE OF NIPPLE LOCATIONS
(shown as a right model)
EXAMPLE OF NIPPLE LOCATIONS
(shown as left model)
FRONTFRONT

5
NORDIC S3
!SAFETY
INSTRUCTIONS
!
• Tumble dryers must not be
connected to the unit.
• The room must have a separate,
adequate air supply when
products such as gas cookers,
gas heaters, fireplaces, wood-
burning stoves, oil-fired boilers,
etc., are used.
• This unit is only designed for
ventilation air in homes and
commercial buildings.
• To maintain a good indoor
climate, comply with regulations
and avoid condensation damage,
the unit must never be stopped
apart from during service/
maintenance or in connection
with an accident.
• The unit must not be operated
without the filters being in place.
• All plumbing work must be
carried out by an authorised
plumber.
• The location of the water battery
must be approved by a plumber
owing to the risk of water leaks.
!
• To avoid the risk of fire, electric
shock or injury, read all the safety
instructions and warning texts
before using the unit.
• All electrical connections must
be carried out by qualified
electricians.
• If the power lead is damaged, it
must be replaced by the
manufacturer, the manufacturer’s
service agent or a similarly
qualified person.
• The unit must not be used to
extract combustible or flammable
gases.
• It is the installer’s responsibility to
carry out a full safety and function
assessment of the appliance.
• Before opening the door: switch
off the heat, let the fans continue
IRUbPLQXWHVWRUHPRYHKRW
air, unplug the unit and wait
2 minutes before opening the
doors, as the unit contains
elements that must not be
touched when hot.
• This appliance may be used by
children of 8 years or above or
by persons with reduced sensory
capacity or reduced physical or
mental capacity, or by persons
lacking experience or knowledge,
provided they have received
instruction in the safe use of the
appliance or are supervised to
ensure safe use and providing
they are aware of the risks.
• The product is not suitable for
use by children. Children must
not be allowed to play with the
appliance. Children must not
carry out cleaning or maintenance
without supervision.
!
• That precautions must be taken
to avoid the back-flow of gases
into the room from the open
flue of gas or other fuel-burning
appliances (for duct and partition
fans).

6
NORDIC S3
1. Planning and preparation
work
1.1. JOINER/FITTER
$LUȵRZ
Check that the air moves from rooms with supply air
valves to rooms with extract air valves.
Kitchen
ΔIWKHNLWFKHQIDQLVGHVLJQHGZLWKDPRWRUVXɝFLHQW
supply air must be ensured. See chap.7.1. Installation
on page 17 and chap.7.2. Adjusting on page 17 for
more information.
Fireplace
:KHQXVLQJWKHȴUHSODFHVXLWDEOHVXSSO\DLUPXVWEH
ensured.
Location in the building
Location of the unit on an internal wall requires
insulation of the wall, interrupted studs and boards,
DQGbGRXEOHSODVWHUERDUGRUDZDOOVWUXFWXUHRIVLPLODU
quality (see chap.2.1. Positioning requirements on page
9).
Positioning must comply with
individual countries’ electrical
safety legislation. Check which
rules apply in your country.
i
Suspension of unit
For screws, suitable noggings (min. 48 x 98 mm) are
required between studs.
See chap.2. Installation on page 8.
Access
The unit must have good access for service/
maintenance. See chap.2.2. Space requirements on page
10 for details.
Fire requirements
$Q\ȴUHVDIHW\UHTXLUHPHQWVPXVWEHFODULȴHG
The positioning of heat sources must be coordinated
with extract air valves so that heat is not sucked straight
out through a valve or door gap.
1.2. PLUMBER
(if the unit has a water battery)
Water pipe layout and placement of the water battery
(channel battery) must be planned. These must be kept
warm to avoid frost damage. A closing damper with
spring must be used. See separate instructions (116166)
that accompany the water battery.
The water battery must be located
in a room with a drain.
1.3. ELECTRICIAN
Power supply
The units have an approx. 2 m cable with plug and
require a single-phase earthed socket nearby. Plug
requirements: 10 A. We recommend a separate circuit
for the unit. For permanent installation, it is possible to
use a fuse in the installation network, provided that it is
DSSURYHGDQGLWPXVWEHSRVVLEOHWRVHFXUHLWLQWKHR΋
position. Or a separate approved service switch can be
installed.
!
It is important for the plug to be
accessible for servicing when the
unit is fully installed.
The unit should be installed with
an earth fault breaker.
When using the app:
The unit must be connected to the internet or an access
point for local communication with the app. A conduit of
at least Ø20 mm is recommended between the unit and
the home’s router for the network cable.
When using the control panel:
Lay a Ø20 mm conduit for running the cable for
controlling the unit between the unit and an easily
accessible place in the home (e.g. outside the bathroom)
DQGWHUPLQDWHZLWKDȵXVKPRXQWHGVLQJOHZDOOER[
Locate the control panel here. The control cable must
be located min. 30 cm away from any power cables. The
control cable must be max. 24 m long to ensure a signal.
For use with accessories:
Lay a Ø16 mm conduit between the unit and the
ORFDWLRQbRIWKHDFFHVVRU\LQTXHVWLRQNLWFKHQIDQ
pressure relay, etc.).
NB! The PG nipple for the power cable must be tightened
with a torque of 2.0 Nm if the cable is replaced.

7
NORDIC S3
51 2 43
!
The installation instructions for
the individual products must be
followed.
For more information on automatic control see
ZZZȵH[LWFRPRUWKHPDQXDOIRU)OH[LW*2DQGWKH
control panel (120018).
Cable type
1 Network cable
2 3-core cable (for e.g. kitchen fan) (DI1&DI2)
3 Cable for control panel (NordicPanel)
4 Not in use (accessory) (Accessories)
5 Power cable, unit
For exact positioning of the electrical bushings, see chap.10.
Dimensioned drawing S3 on page 23.
Positioning of bushings for
electrical conductors.

8
NORDIC S3
2. Installation
1RUGLF6XQLWVFDQEHLQVWDOOHGYHUWLFDOO\RQWKHȵRRU
wall or suspended from the ceiling and can be in hot and
cold zones:
• On the wall (vertically).
(Mounting supplied with unit.)
• 2QWKHȵRRUYHUWLFDOO\
$EVRUSWLRQIHHWPXVWEHȴWWHGDYDLODEOHDVDQDFFHVVRU\
• On the ceiling (vertically).
$FHLOLQJPRXQWLQJPXVWEHȴWWHGDYDLODEOHas an
accessory).
Hanging on wall, e.g. in laundry room.
6WDQGLQJRQDEVRUSWLRQIHHWRQȵRRUHJLQORIW
Hanging on ceiling. (NB: Ceiling mounting is an accessory.)
!
There may be a risk of external
condensation on the unit if it
is placed in a room with high
humidity.

9
NORDIC S3
2.1. POSITIONING REQUIREMENTS
The unit is designed to be installed in boiler rooms,
laundry rooms, stores or other suitable areas. The unit
can be in a cold location.
Positioning must comply with
individual countries’ electrical
safety legislation. Check which
rules apply in your country.
i
The unit should be positioned in such a way that there is
no danger of noise nuisance in nearby rooms.
• If the unit is located in a warm room where a lot
of moisture is generated, condensation may form
on the outside of the unit during periods when the
outside temperature is low.
The base should be stable and level.
BOILER ROOM
BOILER ROOM
LIVING ROOMS
LIVING ROOMS
suitable insulation

10
NORDIC S3
2.2. SPACE REQUIREMENTS
The unit must be installed with suitable space for
VHUYLFLQJDQGPDLQWHQDQFHVXFKDVȴOWHUUHSODFHPHQW
and cleaning of fans and recovery system. See Fig. 1.
These are minimum requirements and only take
service needs into account.
All electrical conductors from the unit must be easily
accessible when the unit is fully installed.
Positioning must comply with
individual countries’ electrical
safety legislation. Check which
rules apply in your country.
i
*For use with a duct cover (accessory)
528 mm (with door)
945 mm
452 mm
5 mm 5 mm
600 mm
ROTOR
300 mm (minimum)*
500 mm (cover)
700 mm
493 mm
528 mm Fig. 1
945 mm
ROTOR

11
NORDIC S3
2.3. WHAT IS SUPPLIED?
3x
5x
1x

12
NORDIC S3
Alternative mounting methods:
1. Vertical mounting on wall
2.4. INSTALLATION
The unit is available in left and right versions (outdoor
air nipple to the left or right), depending on what is the
most favourable in relation to the duct location.
In the case of wall mounting, secure the wall bracket to
the wall and hang the unit in place (Fig. 3). Hold the unit
at an angle when hooking it onto the wall.
The top edge of the wall bracket should be mounted
bPPKLJKHUWKDQWKHWRSRIWKHXQLWȇVEDFNSDQHOΔIbIRU
example, the top of the unit is to be 400 mm below the
ceiling, the wall bracket should be mounted 383 mm
from the ceiling, measured from the ceiling to the top
edge of the wall bracket (Fig. 2).
CEILING
300-500 mm
Fig. 3
Fig. 2

13
NORDIC S3
Alternative mounting methods:
6WDQGLQJRQȵRRU
$EVRUSWLRQIHHWDFFHVVRU\PXVWEHȴWWHGZKHQWKHXQLWLVWRVWDQGRQWKHȵRRU
7KLVUDLVHVWKHXQLWDQGHQDEOHVWKHGRRUUDLOWRFOHDUWKHȵRRU

14
NORDIC S3
3. Duct connection
3.1. CONNECTION TO THE UNIT
See Fig. 4.
(QVXUHWKDWWKHGXFWVDUHȴWWHGWRWKHFRUUHFWQLSSOHbȂ
see the markings on top of the unit and chap.8. System
and general drawings on page 18
Pull the duct insulation well up to the unit.
To avoid the formation of condensation, it is particularly
important for the outdoor and exhaust air ducts to
have insulation and a plastic sleeve pulled right down
WRbWKHbXQLW
Seal the plastic sleeve to the unit with ties.
The duct insulation with
plastic jacket is guided right
down to the polystyrene
around the nipple. It is
very important that there
are no gaps between the
duct insulation and the
polystyrene, as this could
lead to condensation and/
or the formation of ice.
Pull the duct well over the
seal on the nipple.
The plastic sleeve is pulled
right down to the unit.
Fasten the sleeve with ties.
Duct connection
All ducts that pass through a cold zone must be insulated.
The ducts normally require min. 50 mm insulation, with
DQHɝFLHQF\FRUUHVSRQGLQJWRȜ 0.035 W/m.°C or better.
7KHȴWWHULVUHVSRQVLEOHIRUXVHRIWKHUHTXLUHGLQVXODWLRQ
and vapour-proof sleeves in accordance with location/
temperature.
Lay the outdoor air duct with a slight incline towards
WKHbRXWGRRUDLUFDSVRWKDWDQ\ZDWHUWKDWHQWHUVGUDLQV
out again.
Ducts should have good sound insulation, particularly
above the unit.
Fitted ductFig. 4

15
NORDIC S3
4. Electrical work
!
The unit should be installed with
an earth fault breaker. All electrical
connections must be carried out by
DbTXDOLILHGHOHFWULFLDQ
The unit is supplied with a 2 m cable with plug.
The cable exits at the top of the unit and is connected
to a 230 V 50 Hz single-phase earthed power point
that is placed in an easily accessible position close by.
7KHbSRZHUSOXJVKRXOGEHXVHGDVWKHVHUYLFHVZLWFK
See chap.9. Technical data S3 on page 22 for fuse sizes.
Positioning must comply with
individual countries’ electrical
safety legislation. Check which
rules apply in your country.
i
!
Ensure that the plug for the unit is
not boxed in.
Internet access:
For functions such as controlling the unit outside the
home and having access to updates and other cloud
services, the unit must be connected to the internet.
Lay a network cable between the unit and the home’s
router, and connect.
Accessories:
Wireless accessories
A wireless adaptor can be connected to the 4-pole
FRQWDFWPDUNHGȋ$FFHVVRULHVȋ)RUFRQȴJXUDWLRQZLWKWKH
Flexit GO app, see the instructions that come with the
accessories.
Other accessories
Accessories with a closing contact can be connected to
a3-core cable on top of the unit.
Label Colour Function Description
DI1 Brown HIGH (default) )RUFHGDLUȵRZ
DI2 Green COOKER (default) Forced air supply
+24V (REF) White Reference
7KHLQSXWVFDQEHFRQȴJXUHGIRURWKHUIXQFWLRQVZLWK
the Flexit GO app, see instructions in manual (117078).
Control panel:
A control panel can be connected to the 4-pole contact
marked NordicPanel.
For more information, see the instructions for the
control panel (120018).
!
Signal cables must be at least 30
cm from power cables and should
be laid in a 20 mm wiring conduit
at installation. The cables must not
EHbPRUHWKDQPORQJ
4.1. FOR USE WITH A WATER BATTERY
For more information, see instructions (116166) for
water battery.
5. Plumbing work*
*If the unit is going to have heating with a water battery.
All plumbing work must be performed by an authorised
plumber. See instructions (116166) for water battery.

16
NORDIC S3
6. Cover
For service reasons the cover must
have a hatch or removable front.
i
To prevent the transmission of
noise and vibrations, the cover and
the unit should not be in direct
contact with each other.
i
6.1. PREPARATIONS
7KHSODFHPHQWRIWKHFRYHULVQDWXUDOO\D΋HFWHGE\WKH
placement of the unit. Therefore plan the positioning of
both the unit and the cover prior to installation.
7KHUDGLDWHGQRLVHIURPWKHXQLWVSHFLȴHGLQWKHVRXQG
data does not include possible noise from ducting.
7KHbFRYHUVKRXOGWKHUHIRUHEHVRXQGSURRIHGWRR
6.2. FLEXIT DUCT COVER
Flexit duct covers are available as accessories.

17
NORDIC S3
7. Installing and adjusting the
kitchen fan
7.1. INSTALLATION
If an external kitchen fan is going to be used,
documentation regarding installation and adjustment
RIbDLUȵRZUDWHVLVVXSSOLHGZLWKWKHIDQV
7.1.1.Kitchen fan without motor
(connected to unit with duct connection)
The air handling unit has a separate connection point
for kitchen fans without a motor. An electric cable (low-
voltage) must be connected between the unit and the
IDQLQRUGHUWRIRUFHWKHDLUȵRZLQWKHKRRGYLDWKH
switch on the hood.
7.1.2.Kitchen fan with motor
(not connected to unit)
The kitchen fan with motor is not connected to the
unit. It has a completely separate duct system for air
evacuation.
With the kitchen fan it is possible to compensate
IRUbWKHbDPRXQWRIDLUGUDZQRXWRIWKHKRXVH6HH
chap.7.2. Adjusting for more information.
7.2. ADJUSTING
If the kitchen fan is not supplied by Flexit, the fan
VXSSOLHUPXVWSODQDLUȵRZUDWHVIRUH[WUDFWDLULQWKH
hood, and arrange for supply air to the hood.
To reduce the risk of negative pressure in the home,
when using a kitchen fan with an air volume above
approx. 200m3/h is compensated for this with, for
example, an outdoor air valve in the wall.
7.2.1.Kitchen fan without motor
FRQQHFWHGWRbXQLW
To reduce the risk of forced ventilation through the
cooker hood causing imbalance between extract air
DQGVXSSO\DLUWKHȵRZVKRXOGDOVREHDGMXVWHGRQWKH
Ȋ&RRNHUKRRGȋVHWWLQJRQWKHIDQV7KHȵRZEHWZHHQWKH
attachment and the cooker hood can be measured with
DQDLUȵRZPHWHU
The method for adjusting the fan force will vary,
depending on which control unit is used (NordicPanel or
the Flexit GO app). In this description the Flexit GO app
is used.
Procedure:
1. Choose the cooker hood setting with the damper
open and the “cooker hood” signal activated. Adjust
the extract force in the “cooker hood” position until
WKHȵRZRYHUWKHFRRNHUKRRGLVP3/h, to
obtain odour capture of approx. 75%.
 7KHQPHDVXUHWKHȵRZIURPDOODLUH[WUDFWRUVDQG
DGGWKLVȵRZWRWKHȵRZRYHUWKHFRRNHUKRRG
 0HDVXUHDQGDGGXSWKHȵRZVRQDOOVXSSO\DLUXQLWV
Adjust the fan force in the “cooker hood” setting for
WKHVXSSO\DLUIDQWRWKHSRLQWZKHUHWKHȵRZLVWKH
same for both fans.
7.2.2. Kitchen fan with motor
(not connected via duct to unit)
If a kitchen fan with a motor is used, the volume of air
extracted from the building increases. The air handling
unit can be adjusted to provide more supply air than
extract air to compensate for this.
A signal to the unit is required when the kitchen fan
LVbXVHG
Connect an external switch with potential-free ON/OFF
signal to the 3-core cable on the unit (DI2, see wiring
diagram).
Install the pressure relay (accessory).
The cooker hood function works as follows:
The supply air fan will speed up, while the extract air fan
will continue at a low level to partly compensate for the
DLUȵRZWKDWWKHFRRNHUKRRGH[WUDFWVIURPWKHKRXVH
Check the kitchen fan’s maximum capacity (based on the
capacity diagram on the kitchen fan).
(QVXUHWKDWWKHNLWFKHQIDQUHFHLYHVVXɝFLHQWDLUYLDRQH
or more fresh air valves, for example.

18
NORDIC S3
8. System and general drawings
8.1. SYSTEM DRAWING (ELECTRIC HEATING
BATTERY)
(shown as a right model)
Abbreviation Description
B1 Supply air temperature sensor
B3 Extract air temperature sensor
B4 Outdoor air temperature sensor
B6 Exhaust air temperature sensor
EB Heating battery
F10 Overheating thermostat, manual reset
F20 Overheating thermostat, automatic reset
FI1 6XSSO\DLUȴOWHU
FI2 ([WUDFWDLUȴOWHU
M1 Supply air fan
M2 Extract air fan
HR-R Rotary wheel-type heat exchanger
M4 Rotor motor
DA1 Damper
DA2 Damper
8.2. SYSTEM DRAWING (WITHOUT HEATER)
(shown as a right model)
Abbreviation Description
B1 Supply air temperature sensor
B3 Extract air temperature sensor
B4 Outdoor air temperature sensor
B6 Exhaust air temperature sensor
FI1 6XSSO\DLUȴOWHU
FI2 ([WUDFWDLUȴOWHU
M1 Supply air fan
M2 Extract air fan
HR-R Rotary wheel-type heat exchanger
M4 Rotor motor
DA1 Damper
DA2 Damper
B1
M2
M4
HR-R
FI2 FI1
B4
K
DA1DA2
M1
B3 B6
B1
M2
M1
EB
F10
F20
M4
HR-R
FI2 FI1
B4
K
DA1
DA2
B3 B6

19
NORDIC S3
8.3. GENERAL DRAWING
With electric heating battery
(shown as a right model)
No. Abbreviation Description
1 FI1 6XSSO\DLUȴOWHU
2 FI2 ([WUDFWDLUȴOWHU
3 M1 Supply air fan
4 M2 Extract air fan
5 HR-R Rotary wheel-type heat exchanger
6 M4 Rotor motor
7 Control unit
8 K Kitchen hood connection
9 B1 Supply air temperature sensor
10 B3 Extract air temperature sensor
11 B4 Outdoor air temperature sensor
12 B6 Exhaust air temperature sensor
13 EB Heating battery
14 F10 Heating overheating thermostat man.
15 F20 Heating overheating thermostat auto
89
15
13
14
3
5
2
10
6
4
1
11
7
12

20
NORDIC S3
No. Abbreviation Description
1 FI1 6XSSO\DLUȴOWHU
2 FI2 ([WUDFWDLUȴOWHU
3 M1 Supply air fan
4 M2 Extract air fan
5 HR-R Rotary wheel-type heat exchanger
6 M4 Rotor motor
7 Control unit
8 K Kitchen hood connection
9 B1 Supply air temperature sensor
10 B3 Extract air temperature sensor
11 B4 Outdoor air temperature sensor
12 B6 Exhaust air temperature sensor
Without heating
(shown as a right model)
6
4
3
5
8
1
11
7
212
10
9