Zehnder Rittling ComfoAir 70 User manual
ComfoAir 70
Operating and installation instructions for users and installation technicians
3
Legal regulations
All rights reserved.
This manual has been compiled with the utmost care. Nevertheless, the publisher accepts no liability for damage caused by
missing or incorrect details in this manual. We reserve the right at any time and without previous notification to change the
content of these instructions in part of as a whole.
The information contained in these documents is the property of Zehnder Group Deutschland GmbH. Publication, as a whole
or in parts, requires the written approval of Zehnder Group Deutschland GmbH. In-house duplication, designated for the
evaluation of the product or for proper use, is permitted and not subject to approval.
Trademarks
All trademarks are recognized, even if they are not separately labeled. Our trademarks are acknowledged, even if they are not labeled
separately, a missing labeling does not mean that a good or sign is free of trademark rights.
© 2014 Zehnder Group Deutschland GmbH. All rights reserved.
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Contents
1 Preface 6
1.1 Validity
6
1.2 Target group and standard operation 6
1.2.1 Qualification of target group 6
1.2.1.1 Users 6
1.2.1.2 Skilled technicians / installers 6
1.2.2 Standard operation of the unit 6
2 Introduction and safety 7
2.1 Proper use 7
2.1.1.1 ComfoAir 70 ventilation unit 7
2.1.1.2 Control panels 7
2.2 Safety 7
2.2.1 Safety regulation 7
2.2.2 Installation conditions 7
2.2.3 Symbols used 8
2.3 Warranty and liability 8
2.3.1 Warranty provisions 7
2.3.2 Liability 8
3 Instructions for the user and skilled technician / installer 9
3.1 Product description 9
3.1.1 Type label 10
3.1.2 Frost protection 10
3.1.3 Operation in residents with fireplaces 10
3.2 Functionality of the internal and external control panel 10
3.3 Operating functions and signaling from the control panel 11
3.3.1 Automatic operating mode 14
3.3.1.1 Functional principle of HUMIDITY sensor system module 14
3.3.1.2 Functional principle of CO2/ VOC sensor system module 15
3.4 Maintenance by the user 15
3.4.1 Replacing the unit filter 16
3.4.2 Resetting the filter runtime 17
3.4.3 What should I do in the case of a malfunction? 17
3.5 Disposal 17
4 Instructions for skilled installers 18
4.1 Installation requirements 18
4.1.1 Transport and packaging 18
4.1.2 Inspection of the delivered product 18
CONTENTS
5
4.2 Installation 18
4.2.1 General installation instructions 18
4.2.2 Installation preparations 18
4.2.3 Connecting the air ducts (for second room connection) 19
4.2.4 Installing the ventilation unit 23
4.2.5 Electrical connections 26
4.2.5.1 Connection for power supply 26
4.2.5.2 Connecting the internal control panel 28
4.2.5.3 Installing and connecting the sensor system module 28
4.2.6 Configurable operating modes 30
4.2.6.1 Configuration of Automatic operating mode 30
4.2.6.2 Configuration of the boost operating mode 30
4.2.6.3 Configuration of the Absent operating mode 30
4.2.7 Installing the exterior wall hood 30
4.3 Maintenance and repair by the skilled technician 32
4.3.1 Inspection and cleaning of enthalpy exchanger 32
4.3.2 Replacing the fans 34
4.3.3 Exchanging the control board 34
4.4 Visualization of fault notifications 35
4.4.1 Fault codes in the fault status 35
4.5 Technical descriptions 35
4.5.1 Pressure loss-volume flow-characteristic curves for design of adjoining room connection 36
4.5.2 Dimensions 37
4.5.3 Mounting template (figure not true to scale) 38
4.5.4 Wiring schematic 39
5 Appendices 40
5.1 Checklist A Maintenance work for users 40
5.2 Checklist B Maintenance work for skilled technicians 41
5.3 Commissioning and handover protocol 42
5.4 Air volume protocol 43
5.5 Product data sheet 44
5.6 Product label 46
5.7 Conformity 48
5.7.1 Declaration of conformity of the European Union 48
5.7.2 EAC certification of the Eurasian Economic Union 49
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1 Preface
1.1 Validity
This document applies to:
Unit type ComfoAir 70 series
The subject of this manual is the ComfoAir 70 in its various designs variants. Possible accessories are only described to the
extent necessary for appropriate operation in the unit. Please refer to the respective instructions for further information on
accessory parts.
1.2 Target group and standard operation
This manual is for users and skilled installers. The activities should only be carried out by appropriately trained personnel who are
sufficiently qualified for the respective work involved.
1.21 Qualification of target group
1.2.1.1 Users
Users must be instructed by a skilled installer as follows:
Instructions in hazards when handling electrical devices;
Instructions in system operation;
Instruction in the maintenance of the ComfoAir 70;
Knowledge of and compliance with this manual, including all safety instructions.
1.2.1.2 Skilled technicians / installers
Skilled workers must have the following qualifications:
Training in dealing with hazards and risks when installing and operating electrical devices;
Training for the installation and commissioning of electrical devices;
Knowledge of and compliance with the locally applicable building, safety and installation regulations of the relevant local
authorities or municipalities, the regulation of the water utilities and power stations, and other official regulations and
guidelines;
Knowledge of and compliance with this document, including all safety instructions.
Unless otherwise stated in this manual, only a recognized skilled installer is authorized to install, connect, commission, and to
service the ComfoAir 70.
1.2.2 Standard operation of the unit
This unit can be used by children ages 8 and up and also by persons with reduced physical, sensory or mental abilities, or a lack
or experience and knowledge provided that they are under supervision or have been instructed on the safe use of the unit and
understand the risks that result from it. Children must not play with the unit or carry out cleaning and user maintenance without
supervision.
PREFACE
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2 Introduction and safety
The ComfoAir 70 is built in accordance with current technological standards and accepted safety regulations. The unit is subject to
continuing improvement and development. And therefore, is it possible for your unit to deviate slightly from the descriptions in this
document.
2.1 Proper use
2.1.1.1 ComfoAir 70 ventilation unit
The ComfoAir 70 can be used for controlled ventilation in living and office areas (with limitations in the commercial sector) at a
normal room air humidity of approximately 40-70% relative humidity; briefly up to approximately 80% relative humidity. Conditions
outside of this range are considered as misuse. Extreme conditions (e.g. salty air or air polluted with chlorine) can damage the
unit. For reasons of safety, it is prohibited to modify the product or to install components that are not explicitly recommended or
distributed by Zehnder North America for this product.
2.1.1.2 Control panels
The ventilation unit is equipped with an internal control panel. As an option, an external control panel can be connected to the unit
using a cable with maximum 80 ft. (25 m) in length. The external control panel is only suitable for use in indoor areas.
2.2 Safety
Failure to observe the safety regulations, installation conditions, instructions, warnings, and comments in this document can result
in personal injury and/or damage to the unit.
2.2.1 Safety regulations
Do not make any changes to the unit or to the specifications listed in this document. Such changes can cause personal injury
and/or lead to reduced performance in the ventilation system.
Always comply with the general locally-applicable building, safety and installation regulations of the relevant local authorities,
the regulations of the water utilities and power companies, and all other official regulations.
Installation, commissioning, and maintenance must be carried out by an authorized person or company, unless otherwise
stated in this document.
Always disconnect the unit from the power supply before performing repair or maintenance on the ventilation system.
Following installation, all parts that could lead to personal injury are safely shielded by the housing. The unit cannot be opened
without the use of a tool.
Do not disconnect the unit from the power supply unless instructions to the contrary are listed in the manual.
The electronics can be damaged by static electricity; which is why you must always take measures to prevent electrostatic
discharge when handling or connected to the electronics (e.g. anti-static wrist strap).
Replace the filters (at least) every six months. This ensures a pleasant and healthy air quality, and the unit will be protected
against contamination.
Only operate the unit with a closed housing.
Keep this document in the vicinity of the unit during the life of the ventilation unit.
2.2.2 Installation conditions
Check that the installation area is protected from freezing.
The acceptable temperature range for the air being moved is between -4°F (-20°C) and 104°F (40°C).
The unit must not be installed in rooms subject to explosion hazards.
The unit must meet all local and national code requirements. Ensure that proper clearance is provided to other fixtures in
bathrooms or other "wet" rooms.
The unit must not be used for removal of combustible or explosive gases.
The unit can be connected to a 110 or 220 VAC / 50-60 Hz power supply.
To shut down from the main power supply, a disconnection (e.g. breaker or disconnect) system using a contact opening width
in accordance with the conditions for over-voltage category III for complete disconnection, must be provided.
Check whether the electrical installation is suitable for the maximum power of the unit. The values for the electrical input power
can be found in the “Product data sheet” chapter.
Check that the installation area of the unit meets the requirements in the “General installation instructions” chapter.
INTRODUCTION AND SAFETY
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2.2.3 Symbols used
You will find the following symbols in this document:
Important note!
Caution: Risk of affecting the operation of the ventilation system or damaging the unit!
Caution: Risk of personal injury!
2.3 Warranty and liability
2.3.1 Warranty provisions
For full warranty details please visit: http://zehnderamerica.com/faq/
2.3.2 Liability
The ComfoAir 70 was developed and manufactured for the decentralized and semi-centralized ventilation of living areas and
functional rooms.
Every other use is deemed as “improper use”, and can lead to damage of the ComfoAir 70, or to personal injury, for which the
manufacturer cannot be held liable. The manufacturer shall not be liable for any kind of damage that can be attributed to the
following causes:
Failure to observe the instructions listed in this manual pertaining to safety, operation, and maintenance;
Improper installation;
Installation of parts that were not delivered or approved by the manufacturer;
Defects as a consequence of an incorrect connection, improper use, or from system contamination;
Normal wear.
INTRODUCTION AND SAFETY
9
3 Instructions for the user and
skilled technician / installer
3.2 Product description
The ComfoAir 70 is a decentralized or semi-centralized ventilation unit with waste heat recovery for a healthy, well-balanced,
energy-saving, and user-friendly ventilation system. The unit can be used in a single room as an isolated solution or ducted for
multiple rooms. With this ComfoAir 70 application as a semi-centralized ventilation system, air can be extracted from the kitchen
and/or bathroom using adjoining room connections, and the fresh air introduced into the living room and/or bedrooms.
An enthalpy exchanger, which can transfer both humidity and heat, is used in the ComfoAir 70 for energy recovery. The housing
consists of a powder-coated steel plate, as well as covers made of aluminum in the RAL9016 color scheme. The unit body, made
from a high-quality expanded polypropylene (EPP), is used for accommodating the unit components, and also makes sure there is
the necessary insulation and unit soundproofing.
The ComfoAir 70 has two maintenance-free, 24 VDC radial fans with electronic commutation. These fans and the control board
receive the required operating voltage via an integrated 110 or 220 VAC / 24 VDC transformer.
By default, a class G4 (MERV 8) air filter is used in the unit for the outdoor air and the exhaust air. As an option, a class F7 (MERV
13) air filter for pollen can be used for the outdoor air.
The exterior wall hood is made from white aluminum.
The ComfoAir 70 has valves that, when in specific operating modes, automatically close off the outdoor air supply and indoor air
exhaust sections in the unit.
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3.1.1 Type label
The type label identifies the product and can be found underneath the upper canopy on the polypropylene unit core. You will need
the details on the type label for the safe use of the product and to provide information for service. The type label must remain
attached to the product.
3.1.2 Frost protection
The ComfoAir 70 is equipped with an automatic frost protection control system, which prevents the heat exchanger from freezing
should the outside air temperature drop to a very low level. In the first stage of the frost protection mode, the ratio between the
supply air and exhaust air volume flow is automatically adjusted in correlation to the outside air temperature by the control system.
In a second stage, the supply air fan is switched off but the exhaust air volume flow remains unchanged. In outdoor temperatures
lower than 5°F (-15°C), the exhaust air fan is also switched off in the final stage of the frost protection mode. At each stage, a
check is made (after a waiting period) as to whether the temperature conditions with regard to frost protection have changed, and
depending on the result of the plausibility check, whether the relevant frost protection mode is automatically activated.
3.1.3 Operation in residents with fireplaces
Joint operation in residents with fireplaces is only recommended when back-draft prevention devices are installed and in
compliance with applicable laws, regulations, and standards.
3.2 Functionality of the internal and external control panel
The control panels have touch-sensitive buttons, which means the respective operating functions are triggered by touching the
relevant buttons. The ComfoAir 70 can be operated with the internal and/or the external control panel. The button assignments and
the LED signaling in both control panels are identical in terms of functions.
The two buttons are used for setting the various fan speeds and operating modes. The ventilation stages and the Automatic
operating mode are indicated with blue LEDs, and the Service information with red LEDs.
Item Description
AEPP housing, upper part
BExhaust air filter (Class G4 / MERV 8)
CFilter cover
DExterior wall hood (with sealing gaskets on the rear side)
EVentilator wall bracket
FEnthalpy exchanger (moisture heat exchanger)
GConnection socket
HEPP housing unit with integrated fans and cover
IControl board
JLower aluminum canopy, with integrated control panel
KTouch-sensitive control panel
LOutdoor air filter (class G4 / MERV 8 or F7 / MERV 13)
MFilter cover
NUpper aluminum canopy
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3.3 Operating functions and signaling from the control panel
Icon Description Explanation
Fan speed
operating mode
Fan speed 1 (LS1)
The selection for the current fan speed (4 fan speeds with preset speeds for each fan)
is made by using the (-) / (+) buttons.
Touching the (+) button increases the fan speed to the next setting and touching the
(-) button decreases the fan speed to the next setting.
Fan speed 2 (LS2)
Fan speed 3 (LS3)
Fan speed 4 (LS4)
LED1 LIT
LED1-2 LIT
LED1-3 LIT
LED1-4 LIT
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Icon Description Explanation
AUTO LED LIT
Automatic
operating mode
(AUTO)
The Automatic function can only be activated with a sensor system
module.
Touching the (+) button from the currently active LS4 transfers the unit to AUTO
fan speed. AUTO fan speed is exited by touching the (-) button, and the unit is
transferred back to LS4. The Automatic function is in operation when the auto LED is
LIT.
AUTO LED LIT
Bathroom function
operating mode
The Bathroom function can only be activated with a sensor system
module and configured DIP switch setting.
The fans are operated at maximum speed when the relative room air humidity
reaches 80% or greater. If this limit value is not reached, the unit remains in the
previous active operating mode.
LED 1-4 LIT
Boost operating
mode
The boost operating mode temporarily activates fan speed 4 and
requires a configured DIP switch setting.
The boost operating mode is a timed function that can be used to quickly eliminate
odors and moisture. After the boost time has elapsed, the unit will be transferred to
the most recently selected fan speed. The fan speed that was active for longer than
10 seconds is deemed as the last fan speed. When boost is active, the operating
modes “Exhaust air mode” and/or “Supply air mode”, that may be present, are
retained.
A boost duration with 5-120 minutes in 1 minute increments can be set with a
programming module by Customer Service. (Factory setting: 15 minutes)
LED 1 LIT during
the active time
phase
Absent operating
mode
The Absent function is activated for a pre-set time when LS1 fan
speed is selected.
The absent operating mode is used to provide minimal ventilation when the living
space is vacant. The active operating time can be set with a programming module by
Customer Service to 15, 30, 45 or 60 min/h.
(Factory setting: 60 min/h
=
LS1 continuous operation).
LED display for
energy-saving
mode
The LED display on the control panel changes into energy-saving mode after 10
seconds without operator input (unit functions remain active; the LED display is
switched off). If any button is touched, the LED display will be activated again.
Standby operating
mode
The unit can be transferred from LS1 to Standby mode by touching the (-) button.
Both fans are then switched off.
The supply and exhaust dampers are closed automatically!
Standby mode is exited by touching the (+) button. The unit then starts in LS1 fan
speed.
The supply and exhaust dampers are opened automatically!
There is no indication of the standby mode from the LEDs of the control panel.
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Icon Description Explanation
LED1 and the
current LS flash
alternately
Exhaust air
operating mode
Touching the (-) button for 5 seconds while in operating modes LS1 to LS4 activates
or deactivates the Exhaust air operating mode. The supply air fan is switched off; the
exhaust air fan continues to run with the current LS.
The display for the current LS changes every 2 seconds with the flashing LED1.
To avoid condensation appearing on the outer panel, the unit automatically changes
to the Frost protection operating mode when the frost protection temperature is
reached. The supply air fan is operated for several minutes every hour in order to
record the correct outside air temperature.
LED4 and the
current LS flash
alternately
Supply air
operating mode
Touching the (+) button for 5 seconds while in operating modes LS1 to LS4 activates
or deactivates the Supply air operating mode. The exhaust air fan is switched off; the
supply air fan continues to run with the current LS.
If an outdoor temperature of < 55°F (13°C) is not reached, the exhaust air fan will
begin operation.
The display for the current LS changes every 2 seconds with the flashing LED4.
LEDs1-3 flash
Flashing of most
recently active
fan speed when
supply air fan
is switched off
(display of LED1-3
as example)
Frost protection
operating mode
A temperature threshold, which activates the Frost protection operating mode, if
not reached, is stored for each fan speed. Here, the fan speed for the supply air fan
is linearly regulated between the maximum and minimum set point, depending on
the outdoor temperature. The fan speed can continue to be changed in the Frost
protection mode.
The supply air fan is switched off if a second temperature threshold is not reached
within a specific duration.
This status is indicated by the flashing of the LEDs that are indicative of the most
recently active fan speed.
If the outdoor temperature falls below a further temperature threshold, then the
exhaust air fan will also be deactivated, and the unit will have a status of complete
shut-down.
The LEDs for the most recently active fan speed will stop flashing.
The supply and exhaust dampers are closed automatically!
During complete shut-down, the fan speed cannot be changed. Touching the (-) or (+)
button leads to rapid flashing (5x) in LED1-4.
LED1-4 flash
Indication of
disabled states
If, by touching a button, a status is entered that is not available, then this will be
signaled by rapid flashing (5x) in LED1-4.
These states are: disabled standby, disabled supply air or exhaust air mode, and
complete shut-down by Frost protection.
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Icon Description Explanation
LED1 and the
current LS flash
alternately
Indication of filter
inspection
The filters are monitored based on running time. 90 days is the factory preset default.
After the filter runtime has elapsed, a notification of a filter inspection is signaled by
the filter change LED flashing.
Simultaneously touching the (-) and (+) button for 3 seconds allows you to
acknowledge the indication of the filter inspection and to reset the filter runtime.
LED1 and the
current LS flash
alternately
Indication of fault An occurring fault is signaled by the fault LED.
Faults that can be diagnosed by the unit are symbolized by LED1-4 using a fault
code (see 3.4.1).
Simultaneously touching the (-) and (+) buttons for 3 seconds allows you to reset the
fault notification.
3.3.1 Automatic operating mode
Automatic operating mode requires the internal installation and configuration of a sensor system module! The
sensor system modules inserted in the exhaust air section of the ventilation unit are available as optional
accessories.
The Automatic function changes into the frost protection operating mode in the event of frost protection criteria
being present!
The application of the Automatic function follows the logic of a demand-based control system for optimizing the indoor air climate,
and thus increases comfort and quality of life in the living areas. Consequently, an optimized ventilation response and prevention of
mold formation is achieved, which ultimately also leads to an increase in energy savings. The ComfoAir 70 ventilation unit with an
automatic sensor system module is classified in energy efficiency class A.
3.3.1.1 Functional principle of HUMIDITY sensor system module
The HUMIDITY sensor system module is intended to be installed in units for the aeration and ventilation of rooms
that are more likely to have higher humidity; i.e. kitchen, bathroom.
Only one sensor module may be installed in the unit.
The HUMIDITY sensor system module is equipped
with a humidity and temperature sensor and calculates
the relative humidity. The fan speeds are regulated
based on relative humidity in accordance with the
characteristic curve in diagram 1. Dehumidification
performance is reduced as the temperature difference
between the indoor and outdoor air is decreased.
Therefore, the airflow rate is set to 12 CFM (20m3/h)
when the difference between the indoor and outdoor air
temperature is < 9°F (5 K). When the Bathroom function
operating mode is active, the unit will be operated with
the highest fan speed when the relative humidity is ≥
80%.
Diagram 1: Factory setting characteristics curve for Automatic
operating mode with humidity control.
0
5
10
15
20
25
30
0 10 20 30 40 50 60 70 80 90 100
AirflowRate[cfm]
Rela2veHumidity[%]
HumidityControl
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3.3.1.2 Functional principle of CO2-and VOC sensor system modules
The CO2sensor system module and the VOC sensor system module are each combined with a humidity/
temperature sensor.
Only one sensor module may be installed in the unit.
The CO2sensor system module and the VOC sensor system module both offer you the option to evaluate relative air humidity
as well as the air quality for controlling the ventilation unit. The VOC sensor system module detects volatile hydrocarbons (VOC)
and the CO2sensor system module, using NDIR (nondispersive infrared sensor) technology, detects carbon dioxide (CO2). Volatile
hydrocarbons correlate well with the CO2concentration in living spaces. Therefore, the fan speeds are regulated in accordance with
the characteristic curve in diagram 2.
0
5
10
15
20
25
30
400 600 800 1000 1200 1400 1600 1800 2000
AirflowRate[cfm]
CO2Concentra5on[ppm]
CO2/VOCControl
Co2/VOC Concentration [ppm]
The CO2and VOC sensor system modules combined with a humidity/temperature sensor can be deactivated
separately if needed, in accordance with the humidity or air quality control. If both sensor system modules are
configured as active, the unit will be controlled by the sensor that measures the highest levels.
The required hardware settings on the control system are only allowed to be made by competent, qualified
personnel!
3.4 Maintenance by user
If the maintenance work is not carried out regularly, this will affect the functionality of the decentralized ventilation
unit!
Replace the filters at least every six months. This ensures a pleasant and healthy air quality, and the unit will be
protected against contamination.
The maintenance of the ventilation unit for the user is limited to changing the filters periodically and to cleaning the unit on the
surface, if needed. Check the filters if you are requested to do so by the flashing of filter change LED.
Cleaning the surface of the unit, and specifically the control panel, should be done using a damp cloth and a mild
soap solution. Never use just a dry cloth!
Unsuitable cleaning agents are:
Alcohol (> 5%)
Acetone
Benzene or carbon tetrachloride
All types of “strong” cleaning agents
Scouring agents
Glass cleaners and similar
Instructions for units with a second room connection.
The filter mats should be replaced or cleaned on the exhaust air valves (e.g. bathroom, kitchen) every 2 - 3 months or when
deemed necessary by visual inspection.
Diagram 2: Factory setting characteristic curve for
Automatic operating mode with CO2 / VOC control
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3.4.1 Replacing the unit filters
The ComfoAir 70 must not be operated without filters. When changing filters, the unit needs to be set to the
Standby operating mode.
The ComfoAir 70 has two high-quality, MERV 8 (class G4) filters that are installed by default. Retrofitting a pollen filter, MERV 13
(class F7), is possible. This is inserted into the lower filter compartment (outdoor air filter). The filters can be obtained via Zehnder
North America or distributor. The filters in the ComfoAir 70 must be checked in accordance with the relevant notification on the
control panel and, if needed must be replaced. In doing so, proceed as follows:
1. Set the unit into the Standby operating mode.
2. Remove the upper canopy by pulling it out of the guides in an upward direction, as shown below.
3. Insert your finger into the recess between the filter cover and the housing, and pull the filter cover out.
4. Gripping the pulling tabs, carefully pull the filter out of the filter compartment.
Filter compartment for exhaust air filter
(MERV 8 / class G4)
Filter compartment for outdoor air filter
(MERV 8 / class G4 or MERV 13 / F7)
INSTRUCTIONS FOR USER & SKILLED TECHNICIAN
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5. Ensure that the directional arrow of the filter label is pointing to the center of the unit, and insert the new filter into the filter
compartment. Do not use excessive force when inserting the filter.
6. Insert the filter covers so that the filter compartment is sealed.
7. Proceed in the same way for the upper unit filter.
8. Place the upper canopy onto the unit from above. Make sure that it engages into the guide for the lower canopy and the
locking pins into the designated spring clips of the wall bracket.
9. Switch the unit back into the desired operating mode.
3.4.2 Resetting the filter runtime
After completing the filter change, the counter for the filter runtime must be reset. To do this, you can clear the filter inspection
indication again by holding the (-) and (+) button for 3 seconds. The red LED on the control panel, symbolizing the filter change, will
no longer be lit.
3.4.3 What should I do in case of a malfunction?
Contact the installation technician in the case of a malfunction. Note the type of your ComfoAir 70; for more on this, see the type
label underneath the canopy of the unit.
The main power must always be connected, providing the ComfoAir 70 does not have to be shut down due to a serious
malfunction, maintenance work, or due to another urgent cause.
As soon as a main power is disconnected, the living space will no longer be mechanically ventilated. This makes it
possible for problems involving moisture and mold to occur in the living space. Long periods of the unit not
operating, particularly during the summer months, can lead to the accumulation of contaminants inside of the
exterior wall hood and in the EPP housing section of the pipe extension!
It is recommended that the ventilation unit be operated at all times, except during construction and when
maintenance and repair work is required. The unit should be operated in the Absent operating mode for the
duration of an absence!
3.5 Disposal
Discuss what you should do with your ComfoAir 70 at the end of its life cycle, with your supplier. If you cannot return your ComfoAir
70, do not dispose of it in the normal household waste, but rather contact your local authority for options to recycle components or
to process materials in an environmentally-friendly way.
18
4 Instructions for skilled installers
4.1 Installations requirements
The following requirements must be met for the correct installation:
Installation in accordance with the general and locally-applicable safety and installation regulations from, among others, the
power authority, and in accordance with the regulations stipulated in this manual;
Outer wall with a final construction thickness of at least 11” (275 mm);
Sufficient clearance to objects and for maintenance work (at least 4” (10 cm) on each exhaust air side, 8” (20 cm) on the supply
air side, 31-1/2” (80 cm) at the front, and 8” (20 cm) above the unit), with regard to the housing surfaces when installed;
The recommended distance of the intake opening for the outdoor air with respect to the ground is > 39-1/2” (1 m). Ensure that
there is no polluted air in the vicinity of the intake area;
110 or 220 VAC, 50-60 Hz power supply.
4.1.1 Transport and packaging
Proceed with care when transporting and unpacking the ComfoAir 70. The ventilation unit and the outer panel are packed in a
transport-safe box.
Do not damage or dispose of the packaging before final installation of the ventilation unit.
4.1.2 Inspection of the delivered product
If the delivered product is damaged or something is missing, please contact the supplier immediately. Included in the delivery are:
ComfoAir 70, including installation kit
Exterior wall hood, including installation kit
Mounting template as an imprint on the inside of the lid of the box
Operating and installation instructions
Product labels for energy-efficiency label
For units where a second room connection is desired, you should refer to the accessories section in the Zehnder
product program when installing the air ducts.
4.2 Installation
4.2.1 General installation instructions
The ComfoAir 70 is designed for installation in a conditioned space and on a outer wall. The wall must be plumb and the unit must
be installed vertically with the display on the bottom. To mount the ventilation unit, a wall mounting pipe (available separately) must
be installed in the outer wall in advance; please refer to the respective installation instructions enclosed with the wall mounting pipe
(available separately).
When planning the installation location, please note that the minimum clearance needs to be 4” (10 cm) on the
exhaust air side and 8” (20 cm) on the supply air side. For maintenance work, minimal clearances of 31-1/2” (80
cm) in front of the unit and 8” (20 cm) above the unit are to be adhered to!
The location of the unit must meet all local and national code requirements. Ensure that proper clearance is
provided to other fixtures in bathrooms or other "wet" rooms.
4.2.2 Installation preparations
Prior to installing the ventilation unit, an appropriate wall mounting pipe (available separately) must already be installed in the outer
wall at the designated installation location, and flush with the finished wall construction.
The installation of the ComfoAir 70 is designed to be connected to a round wall mounting pipe (available
separately) or a square wall mounting pipe (available separately)!
The square wall mounting pipe (available separately), intended in particular for new buildings, should be integrated in the outer wall
during construction. The round wall mounting pipe (available separately) is preferably used in the refurbishment and reconstruction
of a building, and is inserted in the outer wall by means of a core hole Ø 10-5/8” (Ø 270 mm).
INSTRUCTIONS FOR SKILLED INSTALLERS
19
Observe the respective enclosed instructions on professional installation when installing the wall mounting pipe
(available separately). Use the mounting template in order to transfer all centerings for the holes onto the inner
wall surface.
A 110 or 220 VAC main power supply connection is required to operate the unit.
The main power supply line and, where applicable, the cable to the external control device, must be installed flush-mounted up to
the area of the bottom left side of the unit. The cable ends should protrude approximately 4” (10 cm) out of the wall surface in the
area of the cable entry point.
Unit
power
supply Area of cable
entry point
Connection
box
9-7/8”
(250mm)
6-1/4”
(159mm)
Power
source
External
control device
4-11/16”
(119mm)
2”
(51mm)
2-3/4”
(70mm)
4.2.3 Connecting the air ducts (for second room connection)
The installation of the air ducts and the necessary accessories (adapters, bends, sealing tape) should be done
prior to installing the drywall, if possible.
The following points must be observed when installing the air ducts for a second room connection; ComfoFlex ducts may be used
to provide exhaust and/or ventilation to a second room. The use of the rear duct wall adapter (an accessory available from Zehnder
North America) is required to provide the connection between the CA 70 unit and the ComfoFlex ducting that is typically installed
between the studs within a wall. The wall adapter can only be oriented in the upward or downward direction to avoid interference
with the wall bracket mounting.
Follow the steps below to install the rear duct wall adapter:
1. Determine which secondary room(s) will be exhausted and/or ventilated and route ComfoFlex ducting from the register boxes
and/or diffuser boxes in that room to the location in the room that the CA 70 unit will be installed.
2. Determine the mounting location for the CA 70 unit on the wall and the relative location of the rear duct opening(s).
20
3. Attach the ComfoFlex ducting to the rear duct wall adapter and seal with UL 181a rated duct tape.
4. To ensure proper alignment of the rear duct wall adapter to the CA 70 unit, the adapter(s) must be located per the template on
page 40.
Outer sheathing
Wall studs
5. Remove the outer male-threaded ring from the adapter(s).
6. Once the drywall has been installed, locate the rear duct wall adapter opening and cut the drywall opening to the inside
diameter of the adapter. Repeat if a second adapter was installed.
7. Slip the outer male-threaded ring over one of your hands with the threads oriented toward your fingers. Insert that hand into
the hole just created in the drywall for the duct adapter and hold the adapter securely by the internal middle dividing wall.
Drywall
Wall duct adapter outer male threaded ring
INSTRUCTIONS FOR SKILLED INSTALLERS
Other manuals for ComfoAir 70
7
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Other Zehnder Rittling Ventilation manuals
