Nuaire Group MRXBOX90 S Instruction Manual

1.0 Introduction
The Nuaire MRXBOX90S is a heat recovery unit with an efficiency
of 90% and energy saving constant volume fans. The unit is supplied
ready for use.
The unit has the following functions:
• steplessly adjustable air flow rates through a control panel
• filter indication on the unit
• frost protection system that ensures optimum performance of
the unit, even at very low atmospheric temperatures
• the unit comes ready for use
• all control equipment has been mounted and checked in the
factory
• on installation, the appliance must be connected to the air
ducts, the condensate discharge, the mains supply and the
multiple switch
• the installer can change the desired air flow for every setting
with the aid of the control panel on the unit
1.1 Specification
Supply Voltage 230V~50Hz
Protection Rating IP 31
Dimensions (WxHxD) 560x600x315mm
Duct diameter 125mm
External diameter condensate discharge 20mm
Mass 25 kg
Filter class G4*
Ventilation capacity setting 1, Factory setting 75 m3/h
Ventilation capacity setting 2, Factory setting 100 m3/h
Ventilation capacity setting 3, Factory setting 150 m3/h
Permissible resistance duct system 150 pa at 180 m3/h
* Filters supplied to be replaced post commissioning.
Coding: MRXBOX90S
1.2 Function components
1. Duct spigots. Connections for the input and output ducts.
2. Interior temperature sensor measures the temperature of the air
from the dwelling.
3 Heat exchanger ensures heat transfer between inlet and outlet air.
4. Filters filter both air flows.
5. Atmospheric temperature sensor measures outside air temperature.
6. Communication connection port for cable to multiple switch.
7. Plate fitted with swivel for feeding through power cable.
8. OpenTherm connection. Two pole screw connector for control.
9. Inlet fan feeds fresh air into the dwelling.
10. Basic pcb contains the control electronics for the basic functions.
11. Outlet fan discharges fouled air from the dwelling to the
atmosphere.
12. Computer port connection for service purposes.
13. Control panel Interface between user and control electronics.
14. Connection condensate discharge.
1Leaflet Number 611273 July 2011
MRXBOX90S
Mechanical Ventilation with Heat Recovery
Installation and Maintenance
Before commencing work, please read this
installation guide throughout in conjunction
with the appropriate illustrations.
6
7
9
10
11
12
13
14
1
2
5
4
Figure 1. Exploded view of unit
Nuaire Limited Western Industrial Estate Caerphilly United Kingdom CF83 1NA T: 029 2088 5911 F: 029 2088 7033
E: [email protected] W: www.nuaire.co.uk
3
8
The EMC Directive
2004/108/EC
The Low Voltage
directive
2006/95/EC

2.0 Dimensions
3.0 Performance
2Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
560
VIEW FROM FRONT SIDE VIEW
VIEW FROM TOP
4 x 125dia spigots
1
2
4
3
315
290
79
213
77
75
600 45
248
145
BOTTOM VIEW
77
168 125
125
Resistance Duct Pressure (Pa)
Flow Rate m3/h
0 25 50 75 100 125 150 175 200
300
250
200
150
100
50
0
63
48
54
43
31
37
25
23
21
28
17
11
12
9
13
15
8
66
53
58
Note: The value stated in the circle is the capacity per fan (in watts).
Dimensional references:
1 = spigot to dwelling. Supply (warmed fresh air)
2 = spigot to outside. Exhaust (cool stale air)
3 = spigot from dwelling. Extract (warm stale air)
4 = spigot from outside. Intake (cool fresh air)
A = electric connections
B = detail wall mounting (make sure to correctly place
the rubber strip, washers and caps)
C = connection condensate discharge
A
C
B
Figure 2. Dimensions in mm
Figure 3.

3Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
4.0 Outline description
The Nuaire MRXBOX90S is a highly advanced heat recovery unit,
specially designed for minimum energy consumption and maximum
comfort. This is achieved with the aid of various electronic control
systems. A control unit with microprocessor controls/monitors the
safe operation of the unit and ensures that the air quantities remain
constant, and at the preset values. The MRXBOX90S incorporates a
control panel with display, enabling stepless adjustment of the volume
without having to open the unit. Moreover, information regarding the
operation can be read out from the outside of the unit.
4.1 LED display system and
operating panel
The MRXBOX90S control panel positioned on the front panel of the
unit can be used to retrieve and modify the settings in the control unit
program.
The control panel has four keys and a display.
1 = Display
2 = Key “OK” (confirm, ready)
3 = Key increase parameter
4 = Function key
5 = Key decrease parameter
On the left the display indicates the ventilation setting or the
parameter type. on the right it shows the readout value, for instance
the preset volume.
Example:
The display now shows that the unit is running at ventilation setting 3
at a flow rate of 150 m3/h.
The four keys have the following functions:
• FFunction key/switching on and off parameter menu
• +next parameter/increase value
• -previous parameter/decrease value
• OK Switching on and off settings menu/manual fault reset
Other commands can be entered with key combinations:
• F and +(set), confirm parameter value
• F and - (reset), reset filter indication, parameter value back
to factory setting
• OK and +(ON), switch on unit
• OK and -(OFF), switch off unit
This applies throughout this manual when a key has to be pressed,
The key in question is printed in quotation marks and in bold.
Example: - press key “OK”.
4.2 Frost safety
The frost protection system ensures that the secondary side of the
heat exchanger (outlet side) does not freeze up by introducing an
imbalance between the inlet and outlet air flows, dependent on the
outside air temperature and the pressure across the heat exchanger.
Under severe conditions the inlet air flow will shut down.
NB: Settings are not adjustable.
4.3 Filter indication
The unit is fitted with a filter indication system. It indicates on the
display when the filter is fouled. For more detailed information refer
to section 9.
- RESET -
- ON -
- SET -
- OFF -
3. 1 5 0
1
2
3
4
5
Figure 4. Control panel
Figure 5.

Any air intake terminal MUST be installed in accordance
with the appropriate regulation.
As a guide, the BS5440 series of British Standards
deals with this issue and currently states that an air
intake must be at a minimum distance of 300mm from a
gas boiler balanced flue. Installers are advised to be
aware of the requirements of this standard when
installing ‘through the wall’ supply air ducting.
Similarly, supply and extract air grilles should be
at least 300mm apart.
4Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
5.0 Installation
Installation must be carried out by competent personnel in
accordance with the appropriate authority and conforming to all
statutory and governing regulations.
All mains wiring must be in accordance with the current I.E.E.
Regulations, or the appropriate standards.
Ensure that the mains supply (Voltage, Frequency and Phase)
complies with the rating label. It is recommended that the connection
to the unit is made with flexible cable.
The unit must be fitted indoors, away from any direct sources of heat,
water spray or moisture generation.
The units condensate drain must be connected to the building foul
water drainage system.
If an extract grille associated with the unit is sited in a room containing
a fuel burning unit, the installer must ensure that air replacement is
adequate for both units. Also ensure that the units external grilles are
located at least 600mm away from any flue outlet.
If the ductwork passes through an unheated loft void or similar
location, it should be insulated.
Certain applications may require the installation of sound attenuation
to achieve the sound levels required.
Unit installation procedure can be summarised as
follows:
1. Placing the unit (5.1)
2. Connecting the ducts (5.2)
3. Connecting the condensate discharge (5.3)
4. Electric wiring diagram:
connecting the multiple switch and, if necessary, the power
supply (5.4)
The MRXBOX90s must be installed in accordance with:
• the regulations for ventilation of dwellings and residential
buildings
• the safety regulations for low-voltage installations (current
IEE regulations)
• the regulations for connection to interior sewers in dwellings
and residential buildings
• any additional regulations of the local utilities
• the installation instructions for MRXBOX90S
5.1 Placing the unit
The MRXBOX90S can be directly mounted to the wall using the
suspension strips supplied for that purpose. For a vibration-free
result the unit must be mounted to a solid wall with a minimum mass
of 200kg/m2. (NB: a gypsum block or metal stud wall does not
suffice. Additional measures such as double panelling or extra studs
are required).
• the unit must be placed level
• the installation room must be such that a good condensate
discharge with air trap and pitch for condensate can be made
• the installation room must be frost-free
• make sure there is a free space of at least 70cm at the front of
the unit and a free headroom of 1.8m for cleaning the filters
and carrying out maintenance
5.2 Connecting ducts
The air outlet duct does not have to be fitted with a control valve; the
unit itself controls the air quantities.
To prevent condensation on the outside of the outside air inlet duct
and the air outlet duct from the MRXBOX90S, these ducts must be
insulated externally vapour-proof as far as the unit.
Pay attention to crosstalk and installation noise, also for incorporated
ducts. Design the duct with separate branches to the valve to prevent
crosstalk. if necessary, the input ducts must be insulated, for instance
when they are installed outside the insulated shell.
The duct must always have an adequate diameter, of 150mm for air
quantities up to 250 m3/h, a diameter of 160mm for air quantities up
to 325 m3/h and a diameter of 180mm for air quantities up to 400
m3/h. The duct spigots of the unit are fitted with loose sealing rings
160mm diameter.
Figure 6. A duct diameter of 125mm is recommended.

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Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
5.2 Connecting the ducts cont.
Arrange the exterior air supply from the shadowed (North) side of the
dwelling, for instance from the wall or overhang.
• install the discharge duct between the MRXBOX90S and the
roof sleeve in such a manner that surface condensation is
prevented
• always use an insulated ventilation roof sleeve
• the maximum permissible resistance in the duct system is
150 pa at the maximum ventilation capacity. if the resistance of
the duct system is higher, the maximum ventilation capacity will
be lower
• the location of the mechanical ventilation outlet and the sewer
stack vent relative to the inlet must be chosen to prevent
nuisance
• choose the location of the inlet valves to prevent fouling and
draught
Ducting references:
1 = to dwelling. Supply (warmed fresh air)
2 = to outside. Exhaust (cool stale air)
3 = from dwelling. Extract (warm stale air)
4 = from outside. Intake (cool fresh air)
5.3 Connecting the condensate discharge
The condensate discharge line for the MRXBOX90S is fed through the
lower panel. the condensate must be discharged through a
drainpipe. The drain must discharge under the water level in the
U-trap. The condensate discharge comes separately with the unit
and the installer must screw it into the underside of the unit.
This condensate discharge connection has an external connecting
diameter of 20mm. The condensate discharge line can be glued to
it, if necessary using a square bend. The installer can glue the
condensate discharge in the desired position in the lower part of the
unit.
See Figure 8 below for an example of a connection to a drainpipe.
Pour water into the drip tray to create an air trap.
4
2
1
1
3
3
1
Figure 7. Typical installation with unit mounted on wall.
Figure 8.

For good EMC engineering practice, any sensor cables
or switched live cables should not be
placed within 50mm of other cables or on the same
metal cable tray as other cables.
Isolation - Before commencing work make sure
that the unitis electrically isolated from the mains supply.
Please note this product must be earthed.
6Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
5.4 Electrical connections
Three Position switch
The unit is supplied with a three position speed control switch. This is
connected to the unit via a multi-core cable (supplied).
Additional switches (not supplied)
In order to boost the unit via additional remote switches, the 3
position switch must be used. On the rear of the position switch are
four terminals marked 1 - 4 (see fig. 9 below). In order to boost the
unit to high speed the additional switch should be wired to terminals 3
and 4.
To boost to medium speed wire across terminals 1 - 4.
Note: Do not put any voltage to these terminals as it will damage
the unit beyond repair.
All mains wiring must be in accordance with the current I.E.E.
Regulations and must be installed by a suitably qualified person.
Ensure that the mains supply (Voltage, Frequency and Phase)
complies with the rating label.
The Unit should be used with a local double pole isolator switch
having a contact separation of at least 3mm.
The wiring is as follows: L (live) = Brown
N (neutral) = Blue
Pe (Earth) = Green/Yellow
5.5 Wireless Controller (optional)
1. General
If required this optional control (see fig. 10) can be purchased direct
fom Nuaire (Part number MRXBOX90-BS). Wireless remote control
exists from a receiver and a sender (switch). The receiver and the
transmitter have been synchronized and installation is simple and
rapid. A choice can be made from two types of transmitters, (A) with
two positions, (B) with four positions.
The wireless remote control can be combined with a position switch
that is already mounted and in use. Think of a second switch in the
bathroom.
2. Receiver
The receiver as standard is equipped with a cable and small telephone
plug. The telephone plug needs to be plugged into the provided splitter
that in turn has to be plugged in at the upper side of the unit.
You can use 32 transmitters on 1 receiver.
Nuaire can provide you with extra transmitters.
3. Transmitter with 4 positions
Button Description
Push left upper button unit works in position 1
Push left lower button unit works in position 2
Push right upper button unit works in position 3
Push right lower button (<1 sec.) unit works 15 minutes in
position 3
Switches afterwards to position 1
Push right lower button (>1 sec.) unit works 30 minutes in
position 3
Switches afterwards to position 1
4. Combination of a mechanical switch and a radio-
controlled (RC) transmitter
It’s possible to combine 2 RC transmitters with each other.
It’s also possible to combine a mechanical switch with RC transmitter.
Which transmitter or switch is actual is mentioned below:
RC transmitter - RC transmitter The latest change in position
is actual
Mechanical switch - RC transmitter The highest fan-speed position
is actual
5. Installing the wireless remote control
Mounting:
The remote control wall transmitter is a universal, extremely flat
standard switch element that can be integrated into numerous control
programmes by different manufacturers.
The wall transmitters are supplemented with the single or multiple
frames of the desired switch program.
Position 1
Position 2
Position 3
Position 3
on timer
Figure 11. The receiver is standard and equipped with cable and
with a small telephone plug.
Figure 10. Wireless remote control (optional)
Receiver
Mains supply
13
42
Connecting a 2-way
switch for high speed
Connecting a
2-way switch for
medium speed
Figure 9.

7Leaflet Number 611273 July 2011
The switch element is so flat that the frame of the respective switch
program lies directly against the wall. This allows on-wall mounting
without assembly housing.
• Fasten the central plate (the wide notches of the central plate
must be positioned to accept the wall transmitter on the top or
bottom)
• Attach the design frame, intermediate frame, wall transmitter
and actuating rocker to the central plate one after the other
• During installation, be sure to pay attention to the orientation
of the markings “0” and “I” on the wall transmitter and
actuating rocker!
The central plate can be glued or screwed in place and is easy to
attach to glass and plaster. If the surface is structured, make a flat
area so that the central plate will not shift during mounting.
Unevenness can cause malfunctions. This is particularly important
when mounting on rough walls!
1. Screws: Only use correctly sized screws. Remove the central plate
from the wall transmitter and use it as a template to mark the bore
holes. Drill 5-mm anchor holes, fasten the central plate and mount the
switch.
2. Glue: The wall transmitters can be glued onto a flat, smooth
surface like glass, painted walls, tile, furniture, wood, etc. using the
included double-sided mounting film. This adhesive film completely
covers the mounting plate of wall transmitter but not the entire frame.
The use of single-sided decor film (can be purchased from a home-
improvement store) cut to fit the frame size is recommended for
mounting on glass walls. To avoid air bubbles, the decor film should
first be affixed to the glass surface and then the wall transmitter
should affixed using the double-sided adhesive mounting film.
Demounting:
Remove the rocker, release the intermediate frame from the snap
fits on the top and bottom.
Transmission Range:
The following figures for expected transmission range may be used
as a rough guide only:
• Line-of-sight connections: 30m range in corridors, up to
100m in halls
• Plasterboard and dry wood: 30m range, through max. 5 walls
• Bricks and aerated concrete: 20m range, through max. 3 walls
• Ferroconcrete : 10m range, through max. 1 ceiling
Fire-safety walls, elevator shafts, staircases and supply areas should
be considered as screening.
Restriction of transmission range:
• Switch mounted on metal surfaces, or in metal frames (up to
30% loss of transmission range)
• Hollow lightweight walls filled with insulating wool on metal foil
• False ceilings with panels of metal or carbon fiber
• Lead glass or glass with metal coating, steel furniture
The distance between receivers and other transmitting devices such
as computers, audio and video equipment that also emit high-
frequency signals should be at least 0.5m.
5.6 Initialising (also see 6.3)
The MRXBOX90S is fitted with a pressure-controlled filter indication
and frost control. For optimum performance of these features we
recommend you initialise the unit. This will ensure that the system
pressure as function of the quantity is recorded in the memory.
After initialisation, the unit will automatically become operational
again.
Always put the mechanical switch in position 1 (= check mode) for
initialising.
It is important that after initialisation no more changes are made in
the duct system. For that reason, any dampers, grilles and valves
must be installed and adjusted prior to initialisation. In addition, the
unit must be fitted with new, clean filters.
Also remember to switch off any other fans linked to the same duct
system.
6.0 Switching the unit on and off
There are two methods to switch the unit on or off.
1. Standby mode; the unit remains connected to the
mains, when switching off only the fans are stopped.
2. Removing the mains lead from the power supply.
Switching on
• Connect the unit to the mains supply
• Simultaneously press the keys “OK” and “+”
to switch on the unit.
(only possible after the unit has been switched
to standby “OFF” displayed).
The first digit on the display indicates the
position of the 3-way switch.
Switching off
1. Standby mode; simultaneously press the keys
“OK” and “-” to switch off the unit.
The text OFF appears on the display.
2. Mains power: Isolate the unit from the supply.
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
When working on the unit, always disconnect from the
supply by first switching it to standby within the unit and
subsequently isolating from the mains supply.
Unit must not be switched off, product is
designed to run continuously.

6.1 Setting the air quantity
The air quantities of the MRXBOX90S for settings 1, 2 and 3 are
factory-set at 75, 100 and 150 m3/h respectively.
The performance of the unit depends on the quality of the duct
system as well as on the filter resistance.
Important:
Setting 1: must always be lower than setting 2.
Setting 2: must always be lower than setting 3.
Setting 3: adjustable between 50 and 180 m3/h.
If these conditions are not complied with, the air quantity of the
higher setting will automatically be adjusted.
The air quantities can be modified as follows (as an example here
the air quantity for setting 3 will be changed from 150 to 180 m3/h).
1. Press key "F" for 3 seconds to activate
the settings menu.
2. Use key “+” to select the desired parameter
(U1 = setting 1, U2 = setting 2, U3 = setting 3).
Settings U4 and U5 do not apply to this unit.
3. Press key "OK" for 1 second to display the
selected parameter value.
4. The selected parameter value can be changed
using keys "+" or “-”.
5. The modified setting can now:
A. Be saved and stored
B. Be removed
C. Be restored to factory setting
A. Simultaneously press keys “F” and “+” (first
press “F” and then “+”) to save the modified
setting; this value now blinks 3x to confirm that
it has been stored. The value remains on the
display.
Press key "OK" to return to the settings menu;
if required other settings can now be modified.
(step 2 - 5). Continue with item 6.
B. Press key "OK" to return to the settings menu;
without saving the modified setting.
The previous setting will be maintained.
Continue with item 6.
C. Simultaneously press keys “F” and “-” (first
press “F” and then “-”) to go back to factory
setting. The factory setting will blink 3x and
remains at that value. The modified setting has
now been removed and the factory setting
remains on the display.
Press key "OK" to return to the settings menu;
If required several settings can now be
modified. (see item 2 to 5) Now continue with
item 6.
6. Press key "F" for 1 second to leave the
settings menu.
8Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
- RESET -
- ON -
- SET-
-OFF -
0
5
1

6.2 Other user settings
In addition to the air quantities per setting, the user can also adjust
the following parameters.
U4. Minimum atmospheric temperature bypass. this is the minimum
atmospheric temperature at which the bypass opens, also when the
indoor temperature satisfies the conditions. (Factory set @ 10oC).
U5. Minimum indoor temperature for the bypass. this is the minimum
indoor temperature at which the bypass opens, when the atmospheric
temperature also satisfies the conditions. (Factory set @ 22oC).
These two setting possibilities are made in the same manner as
described in section 6.1. Refer to the table in section 6.12 for the
factory settings 4.2.
6.4 Installer settings
Various other settings of the control unit can also be modified.
Because some settings have an influence on the correct operation of
the unit, these have been placed in a separate installer parameters set.
Consequently, these parameters can only be modified by the installer.
How to modify these is explained in section 6.11.
1. Fixed imbalance
This can be used to keep the pressure in the dwelling at a higher (+)
or lower (-) level than the atmospheric pressure.
Positive imbalance (+): the outlet fan ventilates the set value in
(m3/h) less than the inlet fan.
Negative imbalance (-): the inlet fan ventilates the set value in
(m3/h) less than the outlet fan.
2. No contact step
This setting determines the ventilation position when no switch
contact is connected to position 1; the unit will start running at
the ventilation position set here.
3. These do not apply to this unit
4. Switch line 1 step
Determines what position of the multiple switch matches line 1 on
the control unit.
5. Switch line 2 step
Determines what position of the multiple switch matches line 2 on
the control unit.
6. Switch line 3 step
Determines what position of the multiple switch matches line 3 on
the control unit.
7. Is imbalance permissible?
This determines whether for instance the frost protection may
affect the imbalance.
8, 9, 11, 12 & 14 These do not apply to this unit
10. Constant pressure switched off
Here you can set whether in all cases the fans are running at constant
flow or that they start running at constant pressure when a certain
resistance is exceeded.
13. Filter message
Sets whether the filter message is shown on the display and the LED
of the 3-way switch.
15. Heat recovery configuration
Option setting when heat recovery is used in conjunction with central
heating; only heat recovery or the combination central heating + heat
recovery.
Only heat recovery = 0;
Central heating + heat recovery = 1.
16. Fan setting for central heating + heat recovery
Fan(s) off for central heating + heat recovery (only if 15 = 1).
Setting 16 Situation fan(s)
1 Output fan off
2 Input fan off
3 Both fans off
17. Repeat time in hours
For switching off the fan(s) selected under 16 for central heating +
heat recovery.
18. Maximum switch off time
In seconds for the fan(s) selected under 16 for central heating + heat
recovery.
19. Minimum switch off time
In seconds for the fan(s) selected under 16 after switching on 230V
for central heating + heat recovery.
Refer to the table in section 6.12 for the factory setting.
9Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery

Resetting filter
Switching
off unit
Reset fault
Display user data
Readout menu
installer
Settings menu
User Installer
Display installer data
Activate installer
parameter set
Select parameters
-Standard U1 - U6
1 - 19
-With option pcb U1 - U8
(na) 1 - 19
P1 - P17
Press 'OK' > 1 second to display
the selected parameters
Select parameters
-Standard U1 - U6
-With option pcb (na) U1 - U8
Press 'OK' > 1 second to display
the selected parameter
setting
Modify selected
setting
Modify selected
setting
Store change
Factory setting
Do not store
change
Store change
Factory setting
Do not store
change
Operational
condition
Press keys 'OK' and
'-' >1 second
Press key 'OK
Press key 'OK'
Press key '+' and '-'
Press keys 'OK' and
'+' >1 second
If no key is operated during 5 minutes
Switching
on unit
Press key '+' or '-'
If no key is operated during 5 minutes
Press key 'F' > 1 second
-If no key is operated during 5 minutes
Press key 'OK' > 1 second
-If no key is operated
during 1 minute
Press keys 'F' and 'OK' > 3 seconds
Press key '+' or '-'
Press 'F' or '+'
key >1 second
Press 'F' or '-'
key >1 second
Press 'OK'
key >1 second
If no key is operated
during 1 minute
Press 'F' key
Press 'F'
or '+' key
Press 'F'
or '-' key
Press
'OK' key
Press 'F' key
If no key is operated
during 1 minute
Press key 'OK' > 1 second
if no key is operated
during 1 minute
Press key '+' or '-'
Press key 'F' > 3 seconds
Press keys 'OK' and
'F' > 3 seconds
USER
INSTALLER
Press key '+' or '-'
Press key '+' or '-'
Press key '+' or '-'
Restore all factory
settings
Press 'F' key
10 Leaflet Number 611273 July 2011
Installation and Maintenance MRXBOX90S Mechanical Ventilation with Heat Recovery
6.5 Menu structure display
The menu structure is divided into a readout section and a settings
section. The number of visible parameters depends on the parameter
set. The user has parameter set "user".
The installer has the more comprehensive parameter set "installer",
that can be activated and deactivated by simultaneously pressing key
"F" and key "OK".
Figure 12. The menu structure