Airflow AIROVENT MEV WH4H CENTRAL EXTRACT User manual

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AIROVENT RF MEV WH4H CENTRAL
MECHANICAL EXTRACT
VENTILATION UNIT WITH BUILT-IN
HUMIDITY SENSOR
Installation / Operation and Service Guide
For unit versatility it is supplied without a controller. A
choice of controllers is available at www.airflow.com
80001183 Issue 04 –06/23

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Contents
Introduction..............................................................................3
Unit Dimensions (mm).............................................................4
Unit Specifications...................................................................5
Safety Information and Guidance ............................................6
Transport and Storage.............................................................7
Electrical Installation................................................................8
................................................................................................8
PCB Main Features .................................................................9
Mechanical Installation ..........................................................10
Duct Connections ..................................................................13
Pairing RF Controllers to Unit................................................14
Fan Performance Settings.....................................................16
Dip Switch Settings - Table A................................................17
Dip Switch Settings –Table B ...............................................18
Flow / Pressure Graph A .......................................................19
Flow / Pressure Graph B .......................................................20
Service and Maintenance......................................................21
Unit & Packaging Disposal ....................................................21
Assorted Accessories............................................................24
Warranty................................................................................25

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Introduction
The AIROVENT MEV WH4H CENTRAL EXTRACT is
operated using a Radio Frequency (RF) control, which
means that the central extract unit can be switched
remotely and wirelessly by one or several remote
controls, up to a maximum of 20. The RF control signal
is received by a receiver on the printed circuit board
(PCB) inside the central extract unit. A choice of two
controls is available to be purchased separately:
•RF Controller –Basic (90001489)
•RF Controller with CO2 Sensor (90001490)
Each remote control is intended for exclusive use with
Airflow AIROVENT RF MEV WH4H Central Extract
Units. If bought separately, the remote control must be
connected for the first time to the Airflow ventilation unit
by the installer.

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Unit Dimensions (mm)
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Air to outside
Air from wet rooms

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Unit Specifications
.

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Safety Information and Guidance
IMPORTANT!
Read these instructions carefully before installing
this Mechanical Central Extract Unit.
This manual covers the operation of the AIROVENT RF
MEV WH4H MECHANICAL EXTRACT UNIT WITH
BUILT-IN HUMIDITY SENSOR only. It must therefore
be read in conjunction with the relevant AIROVENT RF
MEV WH4H CONTROLLER User Manual. (Product and
part numbers referenced on page 3.)
Installation of this unit must be carried out by a qualified
and competent person and carried out in clean, dry
conditions where dust and humidity levels are at
minimum.
All wiring must conform to current I.E.E Wiring
regulations –see Electrical Installation on page 8 for
more information. Do not install this unit in areas where
the following may be present or occur; Excessive oil or a
grease laden atmosphere, corrosive or flammable
gases, liquids or vapours, ambient temperatures above
40°C or below 0°C, humidity levels over 90% or a wet
environment.

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Transport and Storage
Units should be stored in their original packaging in a dry
environment protected from the weather. If palletised
quantities are stored or transported, it is recommended
they are covered to protect against particulate damage
and contamination.
Suitable storage temperatures are between –10ºC and
+40ºC.
Care should be taken when re-packing any unit to ensure
the packaging is suitable for the required form of
transport. Damage due to improper transportation,
storage or installation is not covered under warranty. Care
should be taken when lifting. Correct lifting techniques /
apparatus should be used when necessary. Dropping or
sharp blows to the fan can cause damage. Any damage
to the fan or packaging should be inspected by a suitably
qualified person or returned to Airflow Developments Ltd
for inspection before use.
Fans should not be lifted or carried by an electrical lead,
if fitted.

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Electrical Installation
All electrical installations must be carried out by an
approved electrician in accordance with the latest IET
BS7671 Requirements for Electrical Installation, Low
Voltage Directive 2014/35/EU, Machinery Directive
89/392/CE, or the appropriate regulations in the country
of installation. All fans require a 240V 50 Hz single phase
supply. Electric circuit to be used should be isolated
before any work is carried out.
All electrical connections and controls can be found under
the units white, top protective cover held on by locking
tabs. See Fig. 1 - page 12. The units electrical supply
cable must be fitted through the two cable retaining paths
moulded into the unit’s electrical connection tray. See
below:

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All cables should be suitably retained and enclosed where
necessary to prevent damage taking place. A three-pole
lockable isolation switch with a 3mm contact gap should
be used on the mains supply to the unit.
The unit is supplied already fitted with a 1 metre long,
three core cable as standard. Brown = Live. Blue =
Neutral. Green/ Yellow = Earth. This unit should be
protected by using a 3amp inline fuse.
Before function testing the fan, ensure the impeller runs
freely. Also refer to page 12, Pairing Remote Controls.
Function testing should be carried out by switching the fan
on for a short time. When the fan is running, checks
should be carried out for: impeller rotation direction,
undue noise or vibration and power consumption.
Immediately switch off the fan should any problems be
found, and contact Airflow Developments Ltd. Fan motors
used are suitable for continuous running and have a rated
duty type S1 (motor is suitable to this duty type and rating
at which the fan may be operated for an unlimited period).

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PCB Main Features
Push button
Red/ Green
LED
Mains Power
in (230V –50
–1Ph)
Dip switches
Cable to RF
Receiver

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Mechanical Installation
Mechanical installation should only be carried out by a
competent person. Fans are supplied ready for
installation. Care should be taken when removing the fan
from its packaging. Correct lifting techniques/ apparatus
should be used where necessary. Units should be
inspected for any damage. If the Unit is found to be
damaged, it should be returned to the supplier
immediately. Units should be installed to a sufficiently
solid structure giving adequate support. Fixings suitable
for the mounting surface should be used. Airflow
Developments Rubber mount (Part No: 90001294) can
be used to help protect against mechanical noise
transmission into the mounting surface.
Units are mounted by using the four moulded mounting
slots either side of the unit, located at the base of the
extract duct connection box. See Fig. 2, page 12.
Units can be mounted at any angle or position. When
mounting ensure there is no distortion to the fan case or
duct connection box.

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Fig.2 –Mounting Slots
Fig.1 –Top Cover Locking Tabs
Fig.3 –Fan housing lifting handles

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Duct Connections
This unit has three Ø125m and one Ø125/ 160mm
diameter ports moulded on the extract duct connection
box. Three ports are sealed off with blanking plates. The
Ø125/ 160mm diameter port offers a choice of duct size,
this is to help duct system pressure on higher airflows.
Care should be taken when removing the Ø125mm
diameter port and membrane to ensure no excess force is
used which could cause irreputable damage. Failure to
remove the whole membrane could cause excess system
pressure and noise.
Air is expelled to outside from the unit by the Ø125mm
diameter open port in the fan mounting case. See page 4.
If the ducting from this port is installed vertically a
condensation trap should be fitted (Part No: 90001242).
125mm diameter rigid ducting, or a rigid duct with at least
90% free surface area of a 125mm diameter duct should
be used. This is to keep system pressure to a minimum.

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Final connections can be made with a short length of
flexible ducting (Part No. 52641009) and the correct
sealing clamps (Part No. 51849403). The use of
excessive amounts of flexible ducting will result in high
system pressures and a noisy system. Ridged duct
connections should be sealed with a non-hardening
sealant (Part No. 90000356).
Pairing RF Controllers to Unit
To operate the unit, a compatible controller is required
(sold separately). Two RF remote controllers are
available:
•AIROVENT RF MEV WH4H CONTROLLER –
BASIC (90001489)
•AIROVENT RF MEV WH4H CONTROLLER WITH
CO2 SENSOR (90001490)
Each MEV WH4H unit must have at least one RF
Controller paired. Each unit can be paired with up to 20
controllers. A mixture of controllers can be used to suit
application.
Before pairing the unit should be isolated from
the electric supply for a minimum of 5 seconds.
The LED on the controller will flash red then
green.

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AIROVENT RF MEV WH4H
CONTROLLER –BASIC
(90001489)
AIROVENT RF MEV WH4H
CONTROLLER WITH CO2
SENSOR (90001490)
When electric power to the unit is re-installed the LED on
the PCB will flash red and green (PCB Main Features –
Page 10) and then remain green for 3 minutes. In this is
the time RF controllers can be paired to the unit.
Please refer to the instruction leaflet included with the
controller purchased with this unit and follow the pairing
instructions provided. Once the controller(s) has been
paired with the unit, please continue to Fan Performance
Settings in this manual.

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Fan Performance Settings
This unit has two airflow performance curves to choose
from. Each performance curve is broken down into
three bands, low, medium, and high. Each band has
several fan speeds to choose from. All of which can be
set by adjusting the dip switch settings. The dip switch
can be found on the units PCB, which is under the
unit’s white, top protective cover held on by locking
tabs. (See Fig. 1 –page 12). Choice of appropriate
band speed the fan runs at is by using the RF
controllers (Part No’s: 900001489 & 90001490).
Note: When controls are set to “auto” the unit will run
on the low fan speed range until humidity or CO2 is
sensed. When this happens, the unit will automatically
increase the fan speed to the medium range then if
needed to the high range.
Dips witch 8 = Controls the overrun time when the unit
is sensing humidity.
When in the OFF position = 15 minutes.
When in the ON position = 30 minutes.

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Dip Switch Settings - Table A

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Dip Switch Settings –Table B

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Flow / Pressure Graph A

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Flow / Pressure Graph B