Vent-Axia MULTIVENT MV250H Assembly instructions

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PLEASE SAVE THESE INSTRUCTIONS
MULTIVENT
MV250H
MEV Unit
Stock Ref. N°
MV250H 183010C
Installation and Wiring Instructions
220-240V~50Hz
IP22

2
Installation and Wiring Instructions for the Multivent Humidistat Extract Fan.
IMPORTANT:
READ THESE INSTRUCTIONS BEFORE COMMENCING THE INSTALLATION
DO NOT install this product 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 exhaust air temperatures higher than 40°C or less than –5°C.
•Relative humidity above 90%
• Possible obstructions which would hinder the access or removal of the Unit.
•Sudden ductwork bends or transformations close to the Unit.
SAFETY AND GUIDANCE NOTES
A. All wiring must be in accordance with the current I.E.E. Regulations, or the appropriate
standards of your country.
B. The Unit should be provided with a local double pole isolator switch having a contact
separation of at least 3mm. The fuse rating should be 3A.
C. Ensure that the mains supply (Voltage, Frequency and Phase) complies with the rating label.
D. The Unit should only be used in conjunction with the appropriate Vent-Axia products.
E. It is recommended that the connection to the terminal box is made with flexible cable/conduit.
F. The Unit should not be sited within 600mm horizontally of/or 2250mm vertically of a
bath/shower tray, in accordance with the current I.E.E. Regulations for bathrooms.
G. When the unit is used to remove air from a room containing a fuel-burning appliance, ensure
that the air replacement is adequate for both the fan and the fuel-burning appliance.
H. The installer must ensure that the Unit intake is located a minimum of 600mm from any flue
outlet.
I. This Unit is designed as an inline ducted unit to be positioned between lengths of ducting.
Short duct runs terminating within 1.5m must incorporate suitable guards unless the unit is
mounted higher than 2.3m.
J. This Unit should not be used where it is liable to be subject to direct water spray from hoses
etc.
K. This Unit handles moisture-laden air, ensure that a condensation drain is fitted.
L. This appliance can be used by children aged from 8 years and above and persons with
reduced physical, sensory and mental capabilities or lack of experience and knowledge if they
have been given supervision or instruction concerning the use of the appliance in a safe way
and understand the hazards involved.
M.Children shall not play with the appliance.
N. Certain applications may require the installation of sound attenuation material to achieve the
sound levels required.
O. Ducted ventilators must be ducted to the outdoors.
TYPICAL INSTALLATION

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INTRODUCTION NOTES
The MULTIVENT is designed for simultaneous ventilation for a maximum of up to four separate areas such as
bathrooms, kitchens and toilets. The range can be mounted in three different orientations for convenient installation
in roof voids with a height of 250mm or greater. An integral humidistat is provided to automatically trigger an
increased airflow in order to quickly remove any build up of humid air caused by showers, cooking etc.
The MV250H employs a highly efficient backward curved centrifugal motor impeller set. It is designed for continuous
24-hour use and should not be used in conjunction with a delay timer.
HUMIDISTAT
The humidity set point is adjustable between 60% and 90% RH with a mid point potentiometer setting of 75% RH.
Once a humidity level is dedicated above the set point value, the Multivent will initiate a fixed airflow boost cycle
depending on the initial speed setting of unit when the humidity rise was detected.
REMOTE CONTROL (OPTIONAL EXTRA)
Operation of the MV250H can be controlled with a hand held wireless transmitter, available separately. The
transmitter is switchable between low, medium and high (boost) speed operation. The default power-on speed
setting is low. The transmission signal will function over a range of at least 10m through 2 concrete block/beam
floors. 16 unique code selection features are available to match the transmitter to the Multivent receiver and so avoid
any possible cross talk between adjacent property installations.
It is possible to have more than one transmitter unit dedicated to a given Multivent unit and vice versa as the
installation dictates. Each transmitter is provided with a wall mountable holder.
SITING
The MULTIVENT may be mounted in three orientations.
a). Base mounted Installation with ducting radiating out horizontally. The Condensate Drain is on the opposite side
to the exhaust spigot at the base of the unit.
CondensateDrain
On the unit housing.
b). Vertically mounted Installation with the exhaust spigot at top. The Condensate Drain is opposite to the exhaust
spigot at the base of the unit. Additional drainage may be required from the duct connected to the bottom spigot.
Condensate Drain
On the unit housing.
c). Ceiling mounted Installation. The Condensate Drain is opposite to the exhaust spigot under the lid of the unit.
Additional drainage may be required.
Condensate Drain
Under the lid.

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See the dimensional details below for the mounting hole positions.
INSTALLATION
1. Position the MULTIVENT, taking into consideration the position of the rooms to be ventilated, the exhaust
position, the drainage position and the electrical services. Ensure there is adequate access for installation and
maintenance. Securely mount the MULTIVENT through the mounting brackets on the casing using the
appropriate anti-vibration mounts, screws, washers, rubber bushes etc.
2. Where the intake and exhaust ducts are to be connected to the MULTIVENT, remove the spigot caps, if 125mm
ducting is being used. If 100mm ducting is being used, peel out the centre of the cap with a screwdriver as
indicated and leave the cap surround in position. To connect ducting to the base intake, use a suitable adaptor
attached using the 4 holes provided.
3. Ducting passing through an unheated roof void should be insulated. Ducting runs should be as straight as
possible and intake ducting should slope downwards from Under the lid. Connect ducting to the MULTIVENT
spigots and to appropriate ceiling terminations.
4. Select the drain spigot required, remove the “Knockout” and connect a suitable drainage system.
WIRING
WARNING: THE MULTIVENT AND ANCILLARY CONTROL EQUIPMENT MUST BE ISOLATED
FROM THE POWER SUPPLY DURING THE INSTALLATION / OR MAINTENANCE.
THE MULTIVENT UNIT MUST BE EARTHED.
1. Connect mains supply as (Fig. 1).
2. Check that all connections have been made correctly. Ensure that all terminal screws and cable clamps are
securely fastened.
3. The cable entry must be made using a suitable grommet or cable gland.
4. After performing the following set-up instructions, switch the mains supply on and check the system is operating
correctly.
Switched Fused Spu
r
1
9
E
E
5
7
8
N
3
4
2
1 Phase Supply
(220-240V 50Hz).
E
N
L
~
3A FUSE
Fig. 1
Condensate drain
On the unit housing
Condensate drain
Under the lid

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HUMIDITY ADJUSTMENT.
Adjust potentiometer to the required humidistat setting, Fig. 2. To increase the humidistat set point, rotate the
adjuster anticlockwise and to decrease the humidistat set point rotate the adjuster clockwise.
The Multivent reacts automatically to an increase in %RH above the set point value. If high humidity is detected,
the fan speed increases to medium for 30 minutes. At the end of this period, if high humidity is still detected, the fan
speed increases to high for 15 minutes. At the end of this period, if the humidity is low, the fan returns to its original
low setting, but if still high, the fan reverts back to medium speed for 30 minutes and so on.
OVER-HEATING PROTECTION
The MULTIVENT motor is fitted with Standard Thermal Overload Protection. This will automatically switch the fan Off
in the event of a fault condition.
If this occurs isolate the MULTIVENT, check for and remove any obstruction, leave for a short time for the motor to
cool before reconnecting. If this recurs, Isolate the MULTIVENT and call a service engineer.
WIRELESS CONTROLLER (Available stock ref. 426035)
The selection switch in the Multivent unit and the switch in the hand held transmitter must be set exactly the same.
The factory setting is 5678 but it is inadvisable to retain this setting.
a) The Multivent Selection Switch.
Located as shown in Fig 3.
Humidity adjustment
Fi
g
. 2
Fi
g
. 3

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b) The Transmitter Selection Switch
Remove battery compartment cover on the back of the transmitter unit.
Set the transmitter selection switch to the same number sequence as used for the Multivent receiver,
see Fig 4.
Connect battery terminal connector to the battery.
PP3 9V BATTERY
SELECTION SWITCH
c) Humidity Response :
The Multivent reacts automatically to an increase in %RH above the set point value and the manner in which this
triggers will increase airflow depending on the original speed setting, as follows:
Low Speed Setting: If high humidity is detected, the fan speed increases to medium for 30 minutes. At
the end of this period, if high humidity is still detected, the fan speed increases to
high for 15 minutes. At the end of this period, if the humidity is low, the fan returns to
its original low setting, but if still high, the fan reverts back to medium speed for 30
minutes and so on.
Medium Speed Setting: If high humidity is detected, the fan speed stays at medium speed for 30 minutes. At
the end of this period if high humidity is still detected, the speed increases to high
for 15 minutes and drops back to the original medium speed setting at the end of
this period.
High Speed Setting: If high humidity is detected there is no speed change. However, at the end of 30
minutes the boost time-out will automatically reset the fan speed back to low.
In all the automatic humidity operating modes, it is possible to override any humidity cycles in progress and switch
the fan to any other speed. However, if high humidity is still present, the unit will revert back to the appropriate
automatic humidity cycle operation.
Fig. 4

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PRODUCT FICHE
For Residential Ventilation Units (Complying Commission Delegated Regulation (EU)
No 1254/2014)
Name: Vent‐Axia
ModelID(StockRef.):MV250H‐183010‐LDC
SECClassC
SECValue('Average')‐25.71
SECValue('Warm')‐10.21
SECValue('Cold')‐52.78
LabelRequired?(Yes/No=Outofscope)Yes
Declaredas:RVUorNRVU/UVUorBVURVU/UVU
SpeedDriveMulti‐Speed
TypeHRS(Recuperative,Regenerative,None)None
ThermalEff:[(%),NA(ifnone)]N/A
Max.FlowRate(m3/h)489.6
Max.PowerInput(W):(@Max.FlowRate)63.3
LWA:SoundPowerLevel(dB)51.53452373
Ref.FlowRate(m3/s)0.09520
Ref.PressureDiff.(Pa)185
SPI[W/(m3/h)]0.16
ControlFactor&ControlTypology:(CTRL/Typology)
ControlFactor;CTRL0.65
ControlTypologyLocalDemandControl
Declared:‐MaxInternal&ExternalLeakageRates(%)forBVUsor
carryover(forregenerativeheatexchangersonly),
‐&Ext.LeakageRates(%)forDuctedUVUs;
<5%Internal,<5%External
MixingRateofNon‐DuctedBVUsnotintendedtobeequipped
withoneductconnectiononeithersupplyorextractairside;N/A
PositionanddescriptionofvisualfilterwarningforRVUsintended
forusewithfilters,includingtextpointingouttheimportanceof
regularfilterchangesforperformanceandenergyefficiencyof
theunit
N/A
ForUVUs(InstructionsInstallRegulatedSupply/ExtractGrilles
Façade)InF&W
InternetAddress(forDisassemblyInstructions)www.vent‐axia.com
Sensitivityp.Variation@+20/‐20Pa:(forNon‐DuctedVUs)N/A
AirTightness‐ID/OD‐(m3/h)(forNon‐DuctedVUs)N/A
AnnualElectricityConsumption:AEC(kWh/a)1.03
AnnualHeatingSaved:AHS(kWh/a)
AHS:Average28.30
AHS:Warm12.80
AHS:Cold55.36
To achieve the values specified in the above table for Local Demand Control (LDC) the Wireless Controller (426035)
should be used.

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Head Office: Fleming Way, Crawley, West Sussex, RH10 9YX. Tel: [phone] Fax: [phone]
UK NATIONAL CALL CENTRE, Newton Road, Crawley, West Sussex, RH10 9JA
SALES ENQUIRIES: Tel: [phone] Fax: [phone]
TECHNICAL SUPPORT: Tel: [phone] Fax: [phone]
Web:-www.vent-axia.com Email:- [email protected]
As part of the policy of continuous product improvement Vent-Axia reserves the right to alter specifications without notice.
407446C 1217
The Guarantee
Applicable only to products installed and used in the United Kingdom. For details of guarantee outside the United Kingdom contact your local
supplier.
Vent-Axia guarantees its products for two years from date of purchase against faulty material or workmanship. In the event of any part being found
to be defective, the product will be repaired, or at the Company’s option replaced, without charge, provided that the product:-
Has been installed and used in accordance with the instructions given with each unit.
Has not been connected to an unsuitable electricity supply. (The correct electricity supply voltage is shown on the product rating label
attached to the unit).
Has not been subjected to misuse, neglect or damage.
Has not been modified or repaired by any person not authorised by the company.
IF CLAIMING UNDER TERMS OF GUARANTEE
Please return the complete product, carriage paid to your original supplier or nearest Vent-Axia Centre, by post or personal visit. Please ensure
that it is adequately packed and accompanied by a letter clearly marked “Guarantee Claim” stating the nature of the fault and providing evidence of
date and source of purchase.
The guarantee is offered to you as an extra benefit, and does not effect your legal rights