OSTBERG HERU IQ S Manual

HERU IQ S – HERU IQ T
OPERATION & MAINTENANCE |EN
UPDATE
YOUR HERU
To ensure optimal function and
performance of your Heru Air Handling
Unit, please download and install
the latest software version
ostberg.com/updates
UPDATE
YOUR HERU
To ensure optimal function and
performance of your Heru Air Handling
Unit, please download and install
the latest software version
ostberg.com/updates
Other languages in digital format can be downloaded at www.ostberg.com

The manufacturer cannot be held liable for injury and damage to people or property that are caused by incor-
rect installation, start up and/or incorrect use of the unit and/or failure to follow the processes and instructions
that are set out in the manual. For safety reasons it is essential to follow the instructions in the manual. The
warranty will be immediately invalidated in the event of injury that is caused by failure to follow the instruc-
tions. Installation and commissioning must be performed by a professional in order for the warranty to apply.
Shortcuts:
• Log in Service menu: Enter code 1199.
• Bluetooth pairing code: 123456
• Download the latest firmware version: Firmware.
• Download complete Modbus register: Modbus.
FIRMWARE MODBUS
• Download the app: IQ Control App.
APPLE GOOGLE
• Download wiring diagrams via the links below
HERU S HERU T
Information about the products at www.ostberg.com

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EN | Table of content
3
1 PRODUCT OVERVIEW AND USE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 Product description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Control functions ...........................................................5
1.2.1 Regulating the temperature .................................................... 5
1.2.2 Fan capacity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 SAFETY ...........................................................6
2.1 Warnings ..................................................................6
2.2 General safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Declaration of conformity ....................................................8
3 WARRANTY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 Extent of the warranty.......................................................9
3.2 General limitations in the warranty ............................................9
3.3 Limitations in the warranty ...................................................9
3.4 Service conditions during the warranty period ..................................10
3.5 Corrective measures in the event of detected faults ..............................10
4 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1 Installing the IQ Control App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2 Pairing units ..............................................................12
4.3 Entering the basic settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4 IQ Control App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4.1 Home screen ................................................................ 13
4.5 Temperature regulation .....................................................13
4.6 Boost – used for temporarily increased ventilation needs .........................14
4.6.1 Boosting the unit ............................................................ 14
4.6.2 Change operating time for boost ............................................... 14
4.7 Overpressure – is used to facilitate the lighting of a fireplace......................14
4.7.1 Activate overpressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.7.2 Change operating time and compensation for overpressure function. . . . . . . . . . . . . . . . . . 14
4.8 Activate Away mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.9 Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.10 Activate night cooling .....................................................16
4.11 Activate Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.12 Turn the unit off and on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.13 Use the Alarm menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.14 Change settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.15 Update firmware in the ventilation unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5 MAINTENANCE ....................................................18
5.1 Maintenance schedule ......................................................18
5.2 Maintenance ..............................................................18
5.2.1 Maintenance every six months ................................................. 18
5.2.2 Maintenance every year ....................................................... 18
5.3 Preparations ..............................................................19
5.4 Open doors and lid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.5 Remove filters and fans.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5.6 Accessories and spare parts ..................................................21
6 TECHNICAL DATA ..................................................22
7 TROUBLESHOOTING................................................24
7.1 Alarm ....................................................................24
7.2 Other malfunctions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.3 Troubleshooting chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
APPENDIX 1 IQ CONTROL APP – SETUP WIZARD. . . . . . . . . . . . . . . . . . . . . . . . . . . 29

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EN | Product overview and use
1 Product overview and use
1.1 Product description
The energy recovery units HERU S and HERU T are designed for supply air and exhaust air ventilation with
cooling and heat recovery.
The unit
• is equipped with an inbuilt electric after heater.
• is supplied with ePM1 filters.
• is easily controlled using the IQ Control App.
• has as a accessory, a wireless display for operation and monitoring of the unit.
• has Modbus communication via RS485.
HERU S and HERU T can be used in the home, in the office, in apartments etc., where there is a need for:
• high temperature efficiency
• high temperature efficiency
• energy saving
• low sound levels
• safe operation
• high reliability

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EN | Product overview and use
5
1.2 Control functions
1.2.1 Regulating the temperature
The air temperature can be regulated for either constant supply, room or exhaust air temperature.
• To regulate room temperature, a sensor must be positioned in the room (accessory).
• The unit’s inbuilt exhaust air sensor is used for exhaust air temperature.
• If the selected mode does not maintain the desired temperature, regulation moves to the next mode.
There are 5 modes for regulating temperature:
1. Cooling recovery and/or after cooling:
In climate conditions where the rotating heat exchanger is not adequate to achieve the desired supply
air temperature, the unit also controls a cooling battery (e.g. via geothermal heating) when the cooling
recovery from the rotor is not sufficient to maintain the desired temperature. This mode can also be used
if this is not possible using cooling recovery.
2. Cooling recovery:
The rotating heat exchanger starts when cooling recovery is possible in order to maintain a lower supply
air temperature.
3. Outdoor temperature = desired temperature:
When the outdoor temperature is the same as the desired supply air temperature, the rotating heat
exchanger stops.
4. Heat recovery:
The rotating heat exchanger starts to recover the warm indoor temperature.
5. Heat recovery and/or after heat:
In climate conditions where the rotating heat exchanger is not adequate to achieve the desired supply air
temperature, the unit can also control either the inbuilt electric after heater or a heating battery.
1.2.2 Fan capacity
Minimum airflow is set to suit the minimum requirement for ventilation. The basic setting is set to essential
airflow for the ventilation. Maximum airflow is the airflow that is set to obtain higher airflow, if needed.
The airflow (the fan speed) can be controlled by a program planner, which can be programmed with specific
times when the fan will switch from one speed to another.
Using the program planners, different fan speeds can be programmed, such as lowest, highest or standard fan
speed. The fan speed can also be regulated by a carbon dioxide (CO2) and humidity (RH) sensor so that the
unit increases the airflow as much as required in order to maintain the value once the value is exceeded.
”Night cooling” is a function that means you can use the cold outdoor temperature at night to cool the in-
door temperature. The fan speed is boosted when the difference between outdoor and exhaust air tempera-
ture lies within the programmed limits.
2
1
3
4
5

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EN | Safety
2 Safety
2.1 Warnings
WARNING
A warning states a risk of personal injury.
CAUTION
Caution states a risk of damage to equipment.
2.2 General safety
WARNING
In accordance with IEC 60335-2-7.12, this apparatus is not intended to be used by people
(including children) who have physical, sensory or psychological impairment, or lack of experience
and knowledge, unless they have received guidance and instruction on how to use the apparatus
by a person who is responsible for their safety. Children must be supervised to
ensure that they do not play with the apparatus.
WARNING
Watch out for sharp edges and corners on the HERU unit.
WARNING
Protective gloves must be worn due to the risk of cuts or injury.
WARNING
The unit’s ducts must be connected, and doors and/or cover closed and locked before the unit
is started in order to avoid the risk of personal injury from rotating parts.
WARNING
The power supply to the HERU unit must be disconnected for all service and maintenance.
WARNING
The electric after heater may remain hot even after the power has been disconnected for
service and maintenance.
WARNING
All changes or additions of electrical components must be performed by a qualified electrician.
WARNING
Breathing protection and protective clothing must be used due to the risk of breathing in and
spreading dust when handling used air filters.
CAUTION
Always turn off the unit with the IQ Control App or the Display (accessories) before cutting the
power.
CAUTION
The safety switch must not be used for normal starting and stopping of the unit.
Use the IQ Control App.
CAUTION
The safety switch must be set to mode 0 after the unit has been turned off before service can
be started.

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EN | Safety
7
CAUTION
Do not connect an exhaust air type tumble dryer or drying cabinet to the system due
to the high air humidity.
CAUTION
The unit must not be turned off for longer periods unless the duct connections for outdoor air
and extract air are re-plugged due to the risk of condensation and freezing.
CAUTION
In the event of any interruption in power, the settings will be saved. Date and Time are saved for
24 hours. In longer interruptions, Date and Time must be reset.

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EN | Safety
This document is digitally signed.
EU DECLARATION OF CONFORMITY
We hereby confirm that our products comply with the requirements in the following
EU-directives and harmonised standards and regulations.
Manufacturer: H. ÖSTBERG AB
Industrigatan 2
SE-774 35 Avesta, Sweden
Tel No [phone]
Fax No [phone]
http://www.ostberg.com
[e-mail]
VAT No SE556301220101
Products: Bidirectional ventilation unit RVU: HERU® 95 T EC, HERU® 100 T EC, HERU® 160 T EC,
HERU® 200 T EC, HERU® 300 T EC, HERU® 100 S EC, HERU® 160 S EC, HERU® 200 S EC
HERU® 300 S EC, HERU® 70 K EC, HERU® 50 LP EC, HERU® 90 LP EC, HERU® 180 S EC 2,
HERU® 250 T EC, HERU® 130 S EC, HERU® 250 S EC
Bidirectional ventilation unit NRVU: HERU® 400 T EC, HERU® 600 T EC, HERU® 800 T EC,
HERU®, 1200 T EC, HERU® 400 S EC, HERU® 600 S EC, HERU® 800 S EC,
HERU® 1200 S EC, HERU®Select
This EU declaration is applicable for products including our accessories for mounting and installation only if the
installation is made in accordance with the enclosed installation instructions and that the product has not been modified.
Radio Equipment Directive (RED) 2014/53/EU
Harmonised standards:
EN 300 220-2:2018 V3.1.1
EN 303 446-1:2019 (EN 55014-1:2017, A11, EN 55014-2:2015, EN IEC 61000-3-2:2019, EN 61000-3-3:2013, A1)
EN 301 489-3:2019
Machinery Directive (MD) 2006/42/EC
Harmonised standards:
EN ISO 12100:2010
EN ISO 13857:2019
EN 60204-1:2018
EN 60335-1:2012, AC 1, A 13 R1, A 11, A 12, A 13, A 1, A 14, A2, A15
EN 60335-2-40:2003, A13, A2, A12, A1, A11, C1, C2
EN 60335-2-30:2010, A11, A1, A12
Ecodesign Directive 2009/125/EC
Harmonised regulation:
1253/2014 Ecodesign requirements for ventilation units
1254/2014 Energy labeling of residential ventilation units
Standards:
RVU: SS-EN 13141-7:2021 or NRVU: SS-EN 13053:2019
RoHS Directive 2011/65/EU
Harmonised standards:
EN IEC 63000:2018
Avesta 2022-04-25
Mikael Östberg
Product Manager
2.3 Declaration of conformity

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EN | Warranty
9
3 Warranty
The warranty’s validity according to the purchase agreement is calculated from the day of purchase.
3.1 Extent of the warranty
The warranty covers faults that occur during the warranty period that have been notified to the dealer or
which have been verified by H.Östberg AB (underwriter) or the warranty provider’s representative. Faults are
defects in manufacture and materials as well secondary failures that occur due to these.
The above faults must be remedied so that the product is operational.
3.2 General limitations in the warranty
The warranty provider’s liability is limited according to these warranty conditions and the warranty does not
cover injury or damage to people or property. Verbal promises that are made in addition to the warranty
agreement are not binding on the warranty provider.
3.3 Limitations in the warranty
The warranty applies on condition that the product is used in the normal manner or under equivalent cir-
cumstances and that the user instructions are followed.
The warranty does not cover faults that are caused by:
• Transport of the product.
• Unintended use or overloading of the product.
• Failure on the part of the user to follow the instructions regarding installation, use, maintenance and care.
• Incorrect installation or incorrect positioning of the product.
• Conditions that are not the responsibility of the warranty provider, e.g. excessive variations in voltage,
lightning strike, fire and other accidents.
• Repairs, maintenance and changes that are performed by unauthorised parties.
The warranty does not cover:
• Faults that do not affect operation, for example scratches to the surfaces.
• Parts that are exposed to greater risk of fault than normal due to handling or normal wear and tear, for
example lamps, glass, ceramics, paper or plastic parts, filters and fuses.
• Settings, information on use, care, service or cleaning that are typically described in the user instructions, or
damage that is caused by the user failing to observe warnings or installation instructions, or inspection of
such.
The warranty provider is only responsible for the operation if approved accessories are used. The warranty
does not cover product faults that are caused by other manufacturers’ accessories or equipment.
The unit’s current settings must be recorded in the installation and assembly instructions at installation in
order to avoid costs in the event of fault. The warranty provider is not responsible for costs such as adjustment
costs when changing fans and mainboards in the unit.

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EN | Operation
3.4 Service conditions during the warranty period
The conditions apply according to the agreement with the local dealer.
3.5 Corrective measures in the event of detected faults
If a fault is detected, the customer must notify this to the dealer.
Shipping damage must be notified to the shipping agent upon delivery. State which product applies (part and
serial number as per the name plate) and describe the fault and how this has occurred as accurately as possible.
In order for warranty repair to be performed, the customer must demonstrate that the warranty is valid by
presenting a purchase receipt. Once the warranty period has expired, claims that were not made in writing
before expiry of the warranty period will not be valid. In other regards, this shall occur in accordance with the
sales conditions.

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11
4 Operation
For information on active view in the IQ Control App, press the i-button in the App’s status bar.
WARNING
The unit’s duct connections must be duct connected, and doors/cover closed and locked
before the unit is started in order to avoid the risk of personal injury from rotating parts.
CAUTION
The unit must be run constantly and only be stopped for maintenance.
CAUTION
The safety switch must not be used for normal starting and stopping of the unit.
Use the IQ Control App.
CAUTION
In the event of interruption in power, the settings will be stored. Date and Time are saved for
24 hours. After that, Date and Time must be reset. Make sure the unit is started up.
The airflow is regulated in the mode using the IQ Control App. Normal mode is the preset base mode.
Accessible modes:
Away Reduced air flow, can be used when no one is home.
Normal Adjusted at installation, must not be changed.
Boost A higher airflow than normal, medium/max can be selected. This alternative should be
used when there is need for a higher airflow, for example when cooking food, drying
laundry or taking a sauna.
Overpressure Pressure compensation in the event of supplementary heating, for example,
when using an open cooker or stove.
Certain settings are protected by a code so they cannot be changed unintentionally.
NOTE!
If a mode is activated manually, the programmed or previous settings are overwritten.
4.1 Installing the IQ Control App
The free IQ Control App allows the user to control the unit’s functions.
Preparations:
Optional. Make any settings in the home network to guarantee the HERU unit’s continuous connection to
the internet / Cloud.
1. Optional. Connect the HERU unit to the internet-based Cloud service by connecting the internet
connection via the port marked LAN.
2. Download the IQ Control App to your smartphone from your app store.
3. Create an HERU IQ account and log into the app.

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EN | Operation
4.2 Pairing units
1. Make sure the phone’s Bluetooth is turned on.
2. On the HERU Bluetooth gateway (1), take a pointed object and briefly press the button inside the
hole (2) (the larger hole furthest away from the socket).
3. You have one minute to pair the app with the HERU Bluetooth gateway .
4. Open the IQ Control App, in the app’s list of devices, tap the name to pair.
5. The phone will ask if you want to pair (pair and connect).
6. Enter PIN 123456 then OK.
7. If the app is paired with the gateway, the field is highlighted, and the text. Disconnect is displayed.
8. (Optional) Connect your HERU to the internet using a network cable. Use the guide in the IQ Control App
to connect the HERU unit to Cloud. Now you have unlimited remote access to your HERU unit.
In case of problems when pairing the IQ Control App to the HERU Bluetooth gateway, try the following steps:
A. In the phone’s Bluetooth settings, unpair the bluetooth device. To clear all devices from the HERU Bluetooth
gateway, take a pointed object and press and hold the button (see step 2 above) until the led turns off.
Then try to pair again.
B. Turn off Bluetooth on all other phones that are already paired with the HERU unit.
C. If the Bluetooth connection is lost (Home screen is not available in the app), disconnect the network cable
to the HERU Bluetooth gateway and reconnect it again. If still not working, disconnect the power supply to
the HERU unit and then connect it again.
4.3 Entering the basic settings
1. Open the Home screen, select Settings.
2. Select General.
3. Select Language from the list.
4. Enter Time.
5. Select Measurement system from the list.
6. Select Time format from the list.
7. Select Time zone from the list.
2
1

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13
4.4 IQ Control App
4.4.1 Home screen
Shows the status and hotkeys of the Home screen.
The following symbols can be displayed in the status bar:
1. Home screen
2. Information about the active view
3. Status row – shows available functions
- Status cloud connection
- Bluetooth connection
- Air quality compensation for high level of a sensor
- Night cooling active
- Cooler active
- Heater active
- Away mode
- Active program, program no. 5
- Alarm active
Hotkeys to activate or deactivate functions for the modes
4. Temperature
5. Away mode
6. Overpressure
7. Boost
4.5 Temperature regulation
1. Press on the thermometer icon.
2. Set desired temperature. Use the buttons -and +.
NOTE!
If the economy temperature is activated (Activate eco. reference value is on),
you can set both comfort temperature and economy temperature.
3. Press [i] for extend informastion about temperatures.
4. Return to the home screen, by pressing Home.
3
2
1
6
5
4
7

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EN | Operation
4.6 Boost – used for temporarily increased ventilation needs
4.6.1 Boosting the unit
1. Press on the Boost icon. Operation in boost mode is shown with a green circle around
the icon. Deactivate by clicking on the icon again.
NOTE! The preset time for boost operation is 30 minutes.
4.6.2 Change operating time for boost
1. Choose Settings.
2. Select Service.
3. Log in. Enter code 1199.
4. Scroll down to Boost and change the operating time.
4.7 Overpressure – is used to facilitate the lighting of a fireplace
4.7.1 Activate overpressure
1. Press on the Overpressure icon. Operation in overpressure mode is stated with a green circle
around the icon. Deactivate by clicking on the icon again.
NOTE! The preset time for overpressure operation is 15 minutes.
4.7.2 Change operating time and compensation for overpressure function
1. Choose Settings.
2. Select Service.
3. Log in. Enter code 1199.
4. Scroll down to Overpressure and change the operating time.
5. State desired Offset value.
Offset is the difference between supply and exhaust air. Increased to the supply
air fan first. If the supply air fan reaches the limit for maximum fan speed, the exhaust air fan is reduced
until the difference between the fans corresponds to the offset value.

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15
4.8 Activate Away mode
1. Press on the Away icon. Operation in away mode is stated with a green circle around the icon.
The away mode is active until it is manually deactivated by pressing on the icon again.
NOTE!
The away mode is prioritised and overrides the program planner if both are active simultaneously.
4.9 Scheduling
There are two types of schedules: Scheduler for programming the intervals for weekdays and Holiday
scheduler for programming per date. Holiday scheduler overrides Scheduler for weekdays. If the different
schedules coincide with each other, the schedule with the lowest number overrides the other.
The Scheduler can be used in both comfort and economy mode, if the economy temperature is activated.
1. Choose Settings.
2. Select Scheduler.
3. Select type of schedule.
The upper icon automatically activates when one or more program is activated.
When you deactivate this icon, all programs are deactivated.
4. Select Program 1 by clicking on it.
5. Enter the selected value.
6. Select Fan speed. Select Min, Std, Max or Energy saving mode from the dropdown list.
7. If economy temperature is activated, select Temp.mode. Select Comfort or Economy from
the dropdown list.
8. Click on the button Save. The program has activated. In order to deactivate a program,
deactivate the icon to its right.
9. To set several different programs, repeat steps 1 – 7 as required.

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EN | Operation
4.10 Activate night cooling
Night cooling is a temperature regulated boost without heat recovery, where the unit is cooled with cold
outdoor air as needed.
Night cooling is activated when the Extract air temperature is higher than the set Extract air high value and
the out-door temperature is lower than Extract air temperature – (minus) set In/Out diff.
Night cooling is deactivated when the Extract air temperature is lower than the set Extract air low or the out-
door air temperature is higher than the Extract air temperature – (minus) set In/Out diff.
Temp.evaluation Rest mode must be activated if the unit is in standby mode and night cooling is
requested. Temp.evaluation Rest mode checks whether the criteria for activating night cooling has been
fulfilled within the set time intervals.
1. Choose Settings
2. Select Service..
3. Log in. Enter code 1199.
4. Press OK.
5. Select Setup.
6. Scroll down to Night cooling. Press the Activate icon.
7. Enter the selected value.
8. If the unit is in standby and night cooling has been requested, activate Temp.evaluation
Rest mode.
9. Enter the selected value.
4.11 Activate Heater
The Heater is a mounted internal heating element, it helps to achive the adjusted indoor temperature.
Aftercooling is a function to cool the Heater when the unit is stopped, for example when changing the
filter. If Aftercooling is activated, the fans continue to run for two minutes after the unit is switched off. We
recommend always having Aftercooling enabled to prevent the thermal protection from trip and then have
to be reset.
1. Choose Settings
2. Select Service..
3. Log in. Enter code 1199.
4. Press OK.
5. Select Setup.
6. Scroll down to Heater. Under Type –choose Electric.
7. If you can’t find the Heater, activate it in the App under;
Installation > Peripherals > Afterheater >Type – choose Electric.

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17
4.12 Turn the unit off and on
1. Starting the unit. Connect plug/turn on the safety switch.
Start the IQ Control App or Press on the display and click on OK to the question Start unit?.
2. Turning off the unit. Open the main menu, scroll down and select Turn off unit.
4.13 Use the Alarm menu
1. Choose Settings, select Alarms.
2. Select Active alarms to see all active alarms.
3. After managing an active alarm, the active message for the alarm is cleared.
• Click on the alarm to reset it. In the dialogue box displayed, select Reset.
• In order to reset all active alarms, click on Reset all at the bottom in the middle,
in Active alarms.
4. Select Alarm history to see all previous alarms.
5. Return to the home screen.
4.14 Change settings
For all available options, see 1270478 – IQC Manual..
1. Choose Settings, select the desired alternative to be changed.
2. Change the parameters to the desired value.
3. Return to the home screen.
4.15 Update firmware in the ventilation unit
The firmware can be updated from:
1. The IQ Control App – Android via Bluetooth
2. A PC/MAC computer via Bluetooth.
3. An IQC Display (accessory).
Follow the the instructions in the IQ Control App if a notification about an
updated firmware is displayed.

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EN | Maintenance
5 Maintenance
WARNING
In accordance with IEC 60335-2-7.12, this apparatus is not intended to be used by people
(including children) who have physical, sensory or psychological impairment, or lack of experience
and knowledge, unless they have received guidance and instruction on how to use the apparatus
by a person who is responsible for their safety. Children must be supervised to ensure that they
do not play with the apparatus..
CAUTION
Always turn off the unit with the IQ Control App before disconnecting the power.
WARNING
The power supply to the unit must turned off before service or maintenance is started.
WARNING
The electric after heater may still be hot after the power has been disconnected for
maintenance.
The user may perform maintenance according to the user manual in accordance with IEC 6-335–2–40.
Follow the routines for returning and disposing of replaced parts and packaging material.
5.1 Maintenance schedule
Maintenance inspections must be performed according to the schedule below.
The unit must not be repaired directly by the user. Contact the dealer in the event of any fault and
if interruptions to operation are noticed.
Operation Every six months Every year
Inspect the function for supply and exhaust air X
Clean fans and change filter X
5.2 Maintenance
5.2.1 Maintenance every six months
Inspect the function for supply air and exhaust air.
No preparations are required.
1. Inspect the function visually to check that supply air and exhaust air function correctly.
5.2.2 Maintenance every year
Clean fans and change filter.

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5.3 Preparations
Tools
• Torx T25 screwdriver
• Flat-blade screwdriver/13 mm socket (HERU S)
• Flat-blade screwdriver (HERU T)
Disposable items
• Protective gloves
• Breathing protection (minimum class FFP2 as per standard EN149+A1:2009 or equivalent)
• Protective clothing
5.4 Open doors and lid
1. Turning off the unit. Cut the power supply and ensure that it cannot be turned on by mistake.
2. Open the unit’s cover/doors.
HERU S:
1. Remove the four corner covers.
2. Loosen the four screws.
3. Lift off the lid.
HERU T:
1. Use a flathead screwdriver to open the lock on the door, Min 10x1.5 mm and Max 15x2 mm tip.
The slot is 16x2.3 mm
2. Open the doors .
23
1
4
5

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EN | Maintenance
WARNING
Watch out for sharp edges and corners on the unit.
WARNING
Protective gloves must be worn due to the risk of cuts or injury.
5.5 Remove filters and fans.
WARNING
Breathing protection and protective clothing must be used due to the risk of breathing in and
spreading dust when handling a used filter.
1. Pull the filters straight out.
2. Remove the fans’ quick connectors.
3. Unscrew the Torx T25 screws.
4. Carefully draw/lift out the fans from the unit.
5. Unscrew the outer screws from the motor plate.
6. Lift out the motor and fan wheel.
HERU S:
HERU T:
10
6
11
87
6
9
9
8
7
6
69
9
10
11