Vents VUT 350 U EC User manual

OPERATION MANUAL
VUT 350 U EC
VUT 350 EU EC
Air Supply and Exhaust Unit
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VUT 350 (E)U EC
VUT 350 (E)U EC
Introduction
Purpose
Delivery Package
Designation key
Main Technical Specications
Safety Requirements
Design and Operating Logic
Installation and Setup
Condensate Drainage
Connection to Power Mains
Unit Control
Technical Maintenance
Fault Handling
Storage and Transportation Regulations
Manufacturer’s Warranty
Acceptance Certicate
Connection Certicate
Warranty Card
CONTENTS
3
3
3
4
4
6
6
7
9
10
11
18
20
21
21
22
22
22
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INTRODUCTION
PURPOSE
DELIVERY PACKAGE
Unit - 1 item;
Operation Manual - 1 item;
Wall-Mounted Control Panel - 1 item;
Remote Control - 1 item;
Duct temperature sensor (VUT 350 EU EC only) - 1 item;
Shipping Box - 1 item;
Fixture Kit - 1 item.
The present operation manual consisting of the technical details, operating instructions and
technical specication covers the installation of the VUT 350 (E)U EC air handling unit with heat
recovery of VENTS series (hereinafter the Unit).
The unit with heat recovery is designed to save thermal energy by means of thermal energy
utilization and is one of the energy saving components used in buildings and premises. The air
handling unit is a component unit and is not designed for independent operation.
The unit is designed to arrange continuous air exchange by means of mechanical ventilation
in private residences, oces, hotels, cafes, conference rooms as well as recuperation of heat energy
contained in warm stale extract air to warm up the puried supply air.
The transported air must not contain any combustible or explosive mixtures, chemical fumes,
coarse dust, soot, fat or any environment, prolic for the formation of harmful substances (toxic
substances, dust and pathogens) as well as sticky substances and brous materials.
The unit is not intended for operation by children or any persons with reduced
physical, mental or sensory capacities as well persons lacking the required training.
The unit must be handled only by properly qualied personnel after the
appropriate safety instructions.
Install the unit to be out of reach of children.
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VUT 350 (E)U EC
VUT 350 (E)U EC
MAIN TECHNICAL DATA
DESIGNATION KEY
The unit is designed for operation in an enclosed area at ambient temperatures from +1 °C to +
40 °C at relative humidity of up to 80%.
Hazardous parts access and water ingress protection standard:
Unit motors - IP 44;
Unit assembly connected to air ducts - IP 22.
The unit series designations, their main outside and connecting dimensions, appearance and
technical parameters are given on Figure 1 and in Table 1.
The units undergo continuous improvement - therefore, some models may slightly dier from the
ones described herein.
VUT 350 E U EC
MotorType
Electronically Commutated
Air capacity, m³/h
Unit type
VUT - heat recovery ventilation
Electric heater
Spigot Arrangement
U – angular (versatile)
Fig. 1. Outside and Connecting Dimensions of the Unit
700
149
428
600 665
10 m cable
Su. Mo. Th.We.Tu. Fr. Sa.
RT
SET
TIMERO N
TIMER OFF
C
h
88
88 :88
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Model VUT 350 U EC / VUT 350 EU EC
Ventilation Mode Speed 1 Speed 2 Speed 3
Supply Voltage, V/50 Hz 1 ~ 230
Maximum Fan Power, W 36 138 220
Fan Current, A 0,29 0,97 1,48
*Electric Heater Power, kW No / 2,0*
*Electric Heater Current, A no / 8,7*
Total Unit Power, kW 0,22 / 2,22*
Unit Maximum Consumption Current, A 1,5 / 10,0*
Maximum Air Capacity, m3/h 133 270 331
RPM, min-1 1440 2200 2900
Sound Pressure Level at 3m, dB(A) 28 34 41
Transported Air Temperature, °C from - 25 to +60
Casing Material Polymer Coated Steel
Insulation 20 mm, mineral wool
Filter: Air Exhaust/Air Supply G4
Connected Air Duct Diameter, mm Ø 150
Weight, kg 43 / 44*
Recuperating Eciency up to 98%
Heat Exchanger Type Counterow
Heat Exchanger Material Polystyrene
* - only applies to VUT 350 EU EC units
Table 1 . Technical Parameters
Ambient Temperature from 0 °C to 40 °C
Relative Humidity from 5% to 90 % (without condensation)
Cable Section, mm2from 0.18 to 0.35
Material ABS Plastic
Dimensions (WхHхD), mm 86х86х14
Cable Length, m Up to 10
Protection Class IP30
Table 2 . Control Panel Specications
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VUT 350 (E)U EC
VUT 350 (E)U EC
RESTRICTIONS:
• Do not operate the unit outside the permissible temperature range specied in the
Operation Manual or in areas with aggressive admixtures in the air and in explosive
environments.
• Do not connect drying machines or other similar high-power equipment to the
ventilation circuit.
• Do not use the unit for handling air-dust mixtures.
DESIGN AND OPERATING PRINCIPLE
The unit design and operating principle are shown on Fig. 2. The warm stale air from the premises
is supplied to the device and puried in the exhaust lter, passed through the heat exchanger and
then extracted outside via the ducts by the exhaust fan. The cool fresh air from the outside enters
the unit through the air ducts and is stripped of impurities in the supply lter.
The air then passes through the heat exchanger and is delivered into the premises by the supply
fan. The heat exchanger ensures transfer of the heat energy extracted from the warm exhaust air to
the clean outdoor air therefore heating it up.
The air streams do not get mixed in the heat recovery process. The use of a heat exchanger
reduces heat energy losses and, consequently, the heating costs in the cold season.
The VUT 350 EU EC unit is equipped with a 2 kW electric heater with overheating protection
which heats up the supply air. However, supply air heating is not available in the «Night» mode.
The unit design and operating principle are shown on Fig. 2.
The basic conguration includes:
1. Exhaust fan;
2. Supply Fan;
3. Counter-ow heat exchanger;
4. Exhaust air, ltering class G4;
5. Supply air, ltering class G4;
6. Condensate drain pan;
7. Condensate drain tubes;
8. Control Unit;
9. Bypass;
10. Bypass control temperature sensor;
11. Electric heater (only for VUT 350 EU EC unit);
12. Supply air duct temperature sensor.
SAFETY REQUIREMENTS
Installation and operation of the unit shall be subject to the present Operation Manual and the all
appliable local building, re safety, technical and electric regulatory documents.
The unit must be properly earthed.
Prior to connecting the unit to the power mains check for visible damage as well as for any foreign
objects in the fan casing which may damage the impeller blades If necessary, contact the service centre.
ATTENTION!
Make sure to disconnect the unit from the power mains prior to any installation,
maintenance, connection and repair work.
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INTAKE AIR
EXHAUST AIR
SUPPLY AIR
EXTRACT AIR
1 23
5 4
6
7
8
9
10 11
2 m cable
12
Fig. 2. Design and Operating Logic
INSTALLATION AND SETUP
While installing the unit ensure convenient access for subsequent maintenance or repair.
The wall intended for unit installation must be smooth. Any surface irregularities will lead to unit
casing skew and may prevent the unit from operating properly.
The unit installation is shown on Fig. 3:
Secure the wall mount with anchor bolts at the necessary level (all the fasteners are
included in the delivery package).
Hang the unit onto the wall mount.
To ensure correct supply air pre-heating (only applicable to the VUT 350 EU EC) install the duct
sensor into the air duct (item 12 on Fig. 2) at the minimum distance of 1 m from the supply spigot.
The installation steps for the supply air temperature duct sensor is as follows:
drill a Ø 9 mm hole in the air duct;
insert the sensor into the hole;
secure the sensor on site.
It is recommended that the sensor and air duct joint is hermetically sealed.
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VUT 350 (E)U EC
VUT 350 (E)U EC
Fig. 3. Unit Installation
The wall-mounted control panel is installed as follows:
Undo the clips through the access holes in
the bottom of the wall-mounted control panel (Fig. 4).
Remove the back cover.
Disconnect the panel from the
terminal block.
Lay the cable in the wall to the panel
installation site.
Secure the panel back cover to the
wall (Fig. 5).
Fasten the cable to the terminal block.
Clip the wall-mounted front panel in
place.
Fig. 4. Back Cover Removal
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CONDENSATE REMOVAL
Fig. 6. Condensate Removal
min 3°
min 3°
min 100 mm
min 50 mm
CONDENSATE
DRAIN TUBE
CONNECTING
TUBE U-TRAP
CONNECTING
TUBE
SEWERAGE
COLLECTION SYSTEM
The condensate drain pan installed in the heat recovery section has pipes for removing the
condensed uid outside the unit.
Connect the tube, the U-trap (not included in delivery package) and the sewage collection system
with metal or rubber pipes (Fig. 6).The pipe pitch must be at least 3°. Fill up the system with water before
connecting the unit to the power mains! During the operation the U-trap must be always lled with
water. Make sure that the water ows freely into the sewage collection system or otherwise condensed
water may build up in the unit during heat recovery, which consequently, may cause equipment failure
and water ingress into the premises.
Fig. 5. Fixing Back Cover to the Wall
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VUT 350 (E)U EC
VUT 350 (E)U EC
The unit must be connected to the power mains via an automatic cutout switch built into the
stationary wiring with a magnetic breaker with the nominal trip current at least equal to the unit
consumption current (see Table. 1).
The unit enables the following external connection options (X3 connector markings as shown on
the label are given in round brackets, Fig. 7):
Automatic re extinguishing system contact («PK»);
Humidity relay (humidity sensor) contact or CO2 sensor contact («H»);
«3-point control» air damper («Y-N, Y-L, Y-C»).
On connecting the automatic re extinguishing system contact remove the jumper between
terminals X3:1 and X3:2 of the terminal block X3; In this case a normally closed «dry» contact is used
which opens the unit control circuit on re-triggered actuation from the central re-ghting station
cutting the unit power.
The humidity sensor (or CО2sensor) connects to terminals X3:3 and X3:4 of the terminal block X3;
The connection relies on a normally closed «dry» contact. Once closed the unit switches to maximum
speed.
The damper actuator is connected to the terminals X3:5, X3:6 and X3:7 of the terminal block X3. The
same contacts can be used for parallel connection of one more damper.
The additional contacts are connected according to the wiring connection diagram (Fig. 7). The
wires are routed into the terminal box through a sealed lead-in on the top of the unit.
Disconnect the unit from the power supply prior to any work. The unit must be
plugged into a properly installed power socket with an earthed terminal. The nominal
electrical parameters of the unit are given on the manufacturer’s label. Any tampering
with the internal connections is prohibited and will void the warranty.
POWER MAINS CONNECTION
Fig. 7. External Connections Diagram
1
2
3
4
"2"
L
L
ÐÊ ÍY-L
Y-C
Remove the jumper on connecting the
NC contact to the re alarm system
PK - to the re
alarm system
board
РК H
“1”
“2”
“3”
Y-C
C
L
N
Y-L
X3
1
2
3
4
5 7
6
Y-N
H - to the humidity
sensor or CO2
sensor Damper actuator
Y - to the external air
damper
The condensate drainage system is designed for indoor operation at ambient temperatures
above 0 °C. If the expected air temperatures are below 0 °C, the condensate removal system must be
equipped with heat insulation and pre-heating facilities.
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UNIT CONTROL
Fig. 8. Control Panel and Remote Control
Unit On/O
Unit Operation Mode Buttons
(see details below)
Fan Speed Control Buttons
Remote Control
Remote Controller
Unit On/O
Fan Speed Up
On Heater
O Heater
Fan Speed Down
Speed 1 On Speed 3
Speed 2
Scheduled Operation
On
On/O. Timer
Wall-Mounted Control Panel
The unit is controlled by means of the wall-mounted control panel and the remote control (Fig. 8).
1. Unit ON \ OFF.
The unit is activated \ deactivated:
From the wall-mounted control panel by the Unit On/O button ;
From the remote control panel by means of the Unit On/O button .
When the unit is o ( Fig. 9) the wall-mounted control panel display indicates:
Fig. 9. Panel display in the OFF mode
Room temperature;
Day;
Time;
Deactivated status ;
In the TEH blowing mode indicators
and (blowing) are on as well
as the blowing countdown (minutes : seconds) (only
applies to the VUT 350 EU EC).
When the unit is on (Fig. 10) the wall-mounted control panel display indicates:
Room temperature;
Day;
Time;
Fan speed status ;
Timer status;
Timer operation is conrmed by the indicator.
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VUT 350 (E)U EC
VUT 350 (E)U EC
Fig. 10. Display in the ON state
2. Ventilation Mode Control.
The ventilation modes of the unit are selected:
From the wall-mounted control panel: Press the button to increase the speed or press the
button to reduce the speed cyclically (i.e. speed 1 - speed 2 - speed 3).
From the remote control: Press the button to increase the speed or press the button
to reduce the speed cyclically (i.e. speed 1 - speed 2 - speed);
From the remote control: Press the button to select speed 1, press the button to select
speed 2 or press the button to select speed 3 correspondingly.
The wall-mounted control panel display shows the current fan speed status:
Indicator — «Speed 1» mode»;
Indicator — «Speed 2» mode»;
Indicator — «Speed 3» mode».
3. Supply Air Pre-Heating (only applicable to the VUT 350 EU EC unit).
The supply air pre-heater raises the temperature to the pre-set value depending on the duct
temperature sensor setting. The heater is activated / deactivated:
From the wall-mounted control panel: press and hold the button, then press the
button.
From the remote control: to switch the heater on press the button, or press the button
to switch it o.
ATTENTION!
Upon deactivation with a working heater the unit continues operation for an
additional 2 minutes to allow heater cooling. This is conrmed by indicator .
4. Timer.
The timer enables automatic switching of the fans to the maximum speed with automatic reversion
after a selected period of time (20-60 minutes). The timer is activated / deactivated:
From the wall-mounted control panel: To activate the timer press and hold the button
and then press the button. A single press of the button sets the timer to 20 minutes while each
subsequent press increases the timer setting in 10 minute increments. The maximum timer setting is 60
minutes. To deactivate the timer press and hold the button for 3 seconds;
From the remote control: To activate the timer for a 20 minute interval press the button.
The timer can only be set for 20 minutes. to deactivate the timer switch the unit o by means of the
button or the button.
When the timer is o, the indicator
goes on.
Heater status information. Heater
operation is conrmed by the indicator (only
applies to the VUT 350 EU EC).
Open bypass damper is conrmed by
the indicator on the display screen.
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5. Frost Protection.
VUT 350 EU EC: At air temperature in the supply duct upstream of the heat Exchanger in the
range from -7 °C to -15 °C the bypass switches to the automatic regulation cycle (5 minutes in the open
position then 25 minutes in the closed position). At air temperatures below -15 °C the bypass opens for
5 minutes and then closes for 15 minutes.
VUT 350 U EC:The bypass fan switches o on air temperature in the exhaust duct downstream
of the heat Exchanger dropping below +3 °C. When the air temperature raises above the +3 °C threshold
the unit reverts to normal operation.
The bypass damper can be opened or closed manually. While holding the button,
press the button and check that the . indicator appears. This function may be necessary when
recuperation is not required (e.g. when the outdoor temperature is identical or nearly equal to the
indoor temperature). The bypass position is saved in the memory even after the unit deactivation and
reactivation.
Fan Speed Setup Mode.
Ventilation performance settings are made in the fan speed setup mode. The fan speed setup
mode is only available while the unit if o. To access the fan speed setup mode press and hold the
button on the wall-mounted control panel, and then press and hold the button for 3 seconds.
6. Unit Parameter Setup Mode.
Changing ventilation mode performance settings will alter the fan power settings
made at the factory! Fan speed and temperature sensor setup is only possible by means
of the wall-mounted control panel!
Upon entering the setup mode the wall-
mounted panel display screen will show the
and indicators (Fig. 11).
Set the fan speed as necessary using
the and buttons.
While the speed is being set the display screen
will show the currently selected speed , or
.
Fig. 11. Fan Power Adjustment
To change the supply fan power press
and hold the button and press the button
to increase the speed or press the button to
decrease it. Each press of the and buttons
increases or decreases the supply fan power in
1 % increments. With the button pressed the
display screen will indicate the current supply fan
power (Fig. 12).
To change the exhaust fan power press
and hold the button.
Fig. 12. Fan Power Adjustment
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VUT 350 (E)U EC
VUT 350 (E)U EC
Adjust the fan power by using the button to increase it and the button to decrease it. Each
press of the and buttons increases or decreases the exhaust fan power in 1 % increments. With
the button pressed the display screen will indicate the current exhaust fan power.
To exit the fan speed setup mode and save the changes press the button.
The remote control cannot be used to change ventilation mode parameters.
To revert to the factory settings, enter the fan speed setup mode and press the and buttons
simultaneously and hold them for 3 seconds.
Factory fan speed settings:
Speed 1 — 40 %
Speed 2 — 70 %
Speed 3 — 100 %
Duct Temperature Sensor Setup Mode (only applicable to the VUT 350 EU EC unit).
To enter the duct temperature sensor setup mode switch o the unit and simultaneously press the
and buttons on the wall-mounted control panel.
Entering the sensor setup mode is conrmed by
the and indicators.
While in the setup mode the wall-
mounted control panel screen displays the duct
temperature sensor settings (Fig. 13).
The duct temperature sensor setting is
adjusted by pressing the button. The values are
cycled in the range from +16 °C to +30 °C in 2 °C
increments.
To view the current temperature sensor
settings press the button.
Fig. 13. Setting the temperature sensors
Press the button to display the
controller circuit execution code and the rmware
version code on the wall-mounted control panel
screen (Fig. 14).
To exit the duct temperature sensor
setup mode press the button.
Fig. 14. Firmware Version
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5. Filter Replacement Signal.
On elapsing of the lter replacement interval (3 000 hours) the temperature indication on the wall-
mounted control panel display screen will be substituted by the lter replacement alert (Fig. 16).
Fig. 15. Filter Replacement Indication
On lter replacement indications
switch o the unit by pressing the button and
disconnect it from the power mains. Replace the
lter (see the sequence given in the «Technical
Maintenance» section, page 19).
Switch on the unit by pressing the
button on the wall-mounted panel or the
button on the remote control. Then press the
and buttons to reset the service hour counter.
6. Date and Time Setup.
Switch o the unit.
To enter the date and time setup mode press and hold the , then press the button on
the wall-mounted control panel.
While holding the button select the parameter for adjustment by using the and
buttons. The parameter being adjusted is highlighted by blinking.
The date and time parameters are ordered as follows:
1. Minutes;
2. Hours;
3. Day;
4. Date;
5. Month;
6. Year.
Use the and buttons on the wall-mounted control panel to change the selected
parameter setting as necessary.
To exit the date and time setup mode press the button.
7. Scheduled Operation Mode.
To activate the scheduled operation mode press and hold the button, and then press
the button on the wall-mounted control panel. The scheduled operation mode is conrmed by the
indicator on the display screen.
To deactivate the scheduled operation mode press and hold th button, and then press
the button on the wall-mounted control panel.
You can also activate or deactivate the scheduled operation mode by using the button
on the remote control.
The timer will always prevail over scheduled operation.
8. Scheduled Operation Setup.
There are four entries for each day which contain the time for unit switching to a specic fan speed
as well as heater activation or deactivation.
To access the scheduled operation settings switch o the unit by pressing the on the
wall-mounted control panel or the button on the remote control.
Press and hold the button on the wall-mounted control panel, and then press the
button.
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VUT 350 (E)U EC
VUT 350 (E)U EC
Day
Entry Number
1234
Start
Time Mode Heater Status
Start
Time Mode Heater Status
Start
Time Mode Heater Status
Start
Time Mode Heater Status
Mo. 07:00 2 speed O 08:00 1 speed O 17:00 2 speed O 22:00 1 speed O
Tu. 07:00 2 speed O 08:00 1 speed O 17:00 2 speed O 22:00 1 speed O
We. 07:00 2 speed O 08:00 1 speed O 17:00 2 speed O 22:00 1 speed O
Th. 07:00 2 speed O 08:00 1 speed O 17:00 2 speed O 22:00 1 speed O
Fr. 07:00 2 speed O 08:00 1 speed O 17:00 2 speed O 22:00 1 speed O
Sa. 10:00 2 speed O 12:00 2 speed O 17:00 2 speed O 23:00 1 speed O
Su. 10:00 2 speed O 12:00 2 speed O 17:00 2 speed O 23:00 1 speed O
Fig. 16. Scheduled Operation Setup Mode Indicators
Day
Time
Entry
Number Heater
Status
Fan Speed
— Heater O
— Heater On
To select the scheduled operation setup mode parameters hold the button and use the
and buttons to make the selection as necessary.
Press the and buttons to set the parameter values.
Scheduled Operation Setup Mode Parameters (Fig. 16):
• Entry Number — there are four entries for each day.
• Day — day setting.
• Heater Status — heater setting for the current entry. - Heater On, - Heater O.
• Fan Speed — fan speed setting for the current entry.
• Time — time setting for the current entry.
To copy the entries to the following day press and hold the button, then press .
Please note that copying entries from Sunday onto Monday is not possible.
To exit the scheduled operation setup mode press the button on the wall-mounted
control panel or the button on the remote control.
A sample scheduling sequence is given in Table 3. By default the scheduled operation mode is set
up for cooling. To set up the unit for heating operation change the heater settings — set .
Table 3 . Sample programming sequence
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9. Alarms.
In case of an emergency the unit switches o while the alarms are displayed on the wall-mounted
panel screen (Fig. 17). The list of possible alarms is given in Table. 4.
Fig. 17. Alarm Indication
Freezing Protection
Sensor Interruption
Duct Sensor Interruption
TEH Overheating
Temperature Sensor Alarm
ALARM INDICATION ELIMINATION METHOD
TEH Overheating TEH Overheating. Contact the
maintenance service.
Temperature Sensor
Alarm
Short-circuiting of one or two
temperature sensors. Contact the
maintenance service
Duct Sensor Interruption Contact the maintenance service to
restore the duct sensor.
Freezing Protection
Sensor Interruption
Contact the maintenance service to
restore the freezing protection sensor.
Table 4 . Unit-Specic Alarms
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VUT 350 (E)U EC
VUT 350 (E)U EC
TECHNICAL MAINTENANCE
The unit requires maintenance works 3-4 times per year. Maintenance includes regular cleaning and
the following operations:
1. Filter maintenance (3-4 timed per year).
Dirty lters increase air resistance in the system and reduce supply air volume. Clean the lters as
required but at least once in 3-4 months. Use a vacuum-cleaner to remove the contamination or use a
new lter. Contact your seller for new lters.
Filter removal procedure (Fig. 18):
1. Pull the latch plates.
2. Turn the latch plates by 90°.
3. Open the unit access door.
4. Replace the extract and supply lter.
2. Heat exchanger inspection (once per year).
Some dust can get accumulated on the heat exchanger block even in case of regular maintenance
of the lters. To maintain the high heat exchange eciency, regular cleaning is required. To clean the
heat exchanger pull it out of the unit and ush it with warm soap or mild detergent water solution. Re-
install the dry heat exchanger to the unit.
3. Fan inspection (once per year).
Even in case of regular lter maintenance, some dust and grease can get accumulated inside the
fans and reduce the unit performance and supply air ow.
Clean the fans with a soft brush or cloth. No water and abrasive detergent, sharp objects or solvents
are allowed for cleaning to prevent the impeller damage.
4. Condensate drainage (once per year).
The drain pipes may get clogged with extracted particles. Pour some water inside the drain pan and
check the pipe for clogging. Clean the U-trap and drain pipe if required.
5. Supply air ow control (twice per year).
Leaves and other pollutions can clog the supply air grille and reduce the unit performance and
supply air volume. Check the supply grille twice per year and clean it as required.
6. Ductworks inspection (once in 5 years).
Even regular technical maintenance of the unit may not completely prevent dirt accumulation in
the air ducts, which impairs the unit performance. The air duct maintenance mens their regular cleaning
or replacement.
7. Control Unit Maintenance (as required).
The control unit must be serviced by an expert qualied for unassisted operations with
electrical installations up to 1000 V and made familiar with the present operation manual.
Disconnect the unit from the power mains prior to the control unit maintenance.
Control unit maintenance sequence(Fig. 18):
1. Pull the latch plates.
2. Turn the latch plates by 90°.
3. Open the unit access door and release the stoppers by removing two M4 screws. Then take o it
from the door prole.
4. Remove the lters from the unit.
5. Remove the heat exchanger by pulling its band.
6. Remove the screws and take o the protecting cover.
7. Remove the fastening screws of the swivel control unit securing the swivel control unit panel.
Remove the control unit lid for accessing the control unit.
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Fig. 18. Control unit maintenance
1 2
3 4
5 6
7
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20
VUT 350 (E)U EC
VUT 350 (E)U EC
FAULT HANDLING
Trouble Possible Reasons Fault handling
Fan (Fans) will
not start
The unit is not connected to the
power mains.
Make sure that the unit is properly
connected to the power mains and
troubleshoot a connection error, if required.
Supply air
too cold
Clogged extract lter. Clean or replace the extract lter.
Ice buildup in the heat exchanger.
Check for ice in the heat exchanger. If
there is ice in the heat exchanger, let it
melt before switching the unit back on.
Low air ow
Filter, fan or heat exchanger
clogging.
Clean or replace the lters; Clean the fans
and the heat exchanger.
Air handling system clogged or
damaged.
Check for unobstructed diuser opening,
check the exhaust hood and the supply
duct grille and clean them, if necessary;
Make sure that the air ducts are clean and
undamaged.
Noise and
vibration
Fan impellers are clogged. Clean the fan impellers.
Fan fastening bolts are loose. Make sure the fastening screws are tight.
Water leakage The drain line is clogged,
damaged or improperly arranged.
Clean the drain line, if necessary. Check
the drain line slant, inspect the U-trap and
make sure the drain line is equipped with
frost protection.
Troubleshooting and fault handling
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