Vent-Axia MVDC-MS Assembly instructions

PLEASE READ INSTRUCTIONS IN CONJUNCTION WITH THE ILLUSTRATIONS.
PLEASE SAVE THESE INSTRUCTIONS
ORIGINAL ENGLISH INSTRUCTIONS
Stock Ref. N°
MVDC-MS 437634C
MVDC-MSH 443298B
SMV-H 445655B
SMV-HX 495360
SMV-HX CO² 495361
SMV PLUS-H 407849A
SMV PLUS-HX 495362
SMV PLUS-HX CO² 495363
IPX2
220-240V~50Hz
Lo-Carbon
MVDC & SENTINEL
MULTIVENT
RANGE
VENTILATION SYSTEMS
Installation and Wiring Instructions

2
Installation and Wiring Instructions for the Multivent Multi-Speed Extract Fans.
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.
 Subject to direct water spray from hoses.
 Ambient temperatures higher than 40°C
and lower than -20°C.
 Possible obstructions that may hinder
access to or removal of the unit.
 All wiring must be in accordance with the current IEE wiring regulations BS7671, or appropriate standards
of your country. Installation should be inspected and tested by a suitably qualified person after completion.
 Ensure the mains supply (voltage, frequency and phase) complies with the rating label.
 The unit should be provided with a local double pole fused spur fitted with a 3A fuse having a contact
separation of at least 3mm.
 This appliance incorporates an earth connection for functional purposes only
 Precautions must be taken to avoid the back-flow of gases into the building from the open flue of gas or
other fuel-burning appliances.
 This appliance is not intended for use by persons (including children) with reduced physical, sensory or
mental capabilities, or lack of experience and knowledge, unless they have been given supervision or
instruction concerning use of the appliance by a person responsible for their safety.
 Young children should be supervised to ensure that they do not play with the appliance.
 Cleaning and user maintenance shall not be made by children
 The installer is responsible for the installation and electrical connection of the unit on site. It is the
responsibility of the installer to ensure that the equipment is safely and securely installed and left only
when mechanically and electrically safe.
 All regulations and requirements must be strictly followed to prevent hazards to life and property, both
during and after installation, and during any subsequent servicing and maintenance.
 Certain applications may require the installation of sound attenuation to achieve the sound levels required.
 The unit must not be connected directly to a tumble drier.
 The exhaust grille should be located at least 600mm away from any flue outlet.
 This product and associated duct installation should be carried out in accordance with the Domestic
Ventilation Compliance Guide.
 This product contains FCC ID: S9NSPBTLERF
 Bluetooth LE: -12dBm EIRP (63μW), nominal 2450MHz.
 Bluetooth v4.1 compliant
 The module has obtained the RED certificate: No. 0051-RED-0011 REV. 0
 Zirconia Wireless: -14dBm EIRP nominal 868MHz.
 Vent-Axia hereby assure that this type of Bluetooth radio and 868MHz radio
equipment complies with RED Directive 2014/53 / EU
The full text of the EU Declaration of Conformity can be found at the following URL:
https://www.vent-axia.com/range/centralised-mechanical-extract-ventilation-mev

3
INTRODUCTORY NOTES
The MVDC & Sentinel Multivent units are designed for simultaneous extract ventilation of multiple areas
such as bathrooms, kitchens and toilets. The units use a highly efficient backward curved centrifugal motor
impeller set and are designed for continuous 24-hour use.
Depending on the model, they feature either 3 or4 settable speeds and can be configured to change speed
based on a wide range of sensor or control inputs as depicted below
Model
Speed
Max airflow
(m3/hr @0 Pa)
Switched Live
Input (LS)
Analogue
Input 0-10V
Digital
Input
Humidity
Sensor
CO2
Sensor
Wireless
Receiver
MVDC-MS
3
430
Yes
Yes
Yes
No
No
No
MVDC-MS H
3
430
Yes
Yes
Yes
Yes
No
No
SMV H
4
463
Yes
Yes
Yes
Yes
No
No
SMV HX
4
463
Yes
Yes
Yes
Yes
No
Yes
SMV HX Co2
4
463
Yes
Yes
Yes
Yes
Yes
Yes
SMV Plus H
4
573
Yes
Yes
Yes
Yes
No
No
SMV Plus HX
4
573
Yes
Yes
Yes
Yes
No
Yes
SMV Plus HX Co2
4
573
Yes
Yes
Yes
Yes
Yes
Yes
The units can be precisely programmed to determine how they respond to changes in sensor values or the
status of the various signal inputs. The units will run at a Normal flowrate until a sensor or input change
causes it to change speed. In the case of the Switched Live and Digital inputs the units will perform a step
change in speed to the appropriate new level. In the case of the Analogue inputs, Humidity Sensor and
CO2 sensor the unit can be programmed to give a proportional response to the change in conditions.
INSTALLATION
Position the unit, taking into consideration the position of the rooms to be ventilated, the exhaust position
and the electrical services. Ensure there is adequate access for installation and maintenance.
If the unit is sited in the heated void of the dwelling a condensate drain should not be necessary.
When sited in a cold loft, consideration should be given to fitment of a condensate drain. Alternatively the
unit and ducting can be externally insulated to minimize condensation within the units housing.
To reduce the system resistance in your duct system, and therefore lower the speed, power consumption
and noise of the fan, follow these guidelines:
1.1. Keep the length of duct runs to a minimum, particularly the exhaust duct run.
1.2. If you need to use flexible ducting, make sure that it is fully extended and not crushed,
sagging or torn.
1.3. Try to minimize the use of diffusers/valves by having similar length duct runs to the inlets.
1.4. The bend radius (measured to the inside of the bend), should be at least 1x the duct diameter.
1.5. Avoid having any bends, filters or other obstructions within 250mm of the fan inlets and outlet.
Securely mount the unit through the mounting holes on the casing using appropriate fixings for the
mounting substrate. Anti-vibration mounts; acoustic mat or rubber bushes can also be used.
Fixings (not supplied) to be capable of securing 4 x the weight of the unit. Unit weight: 4.1kg

4
To maintain the IPx2 rating of the unit, the unit must not be mounted with the cover removal slots
facing upwards, or at an angle where they are visible from above.
All other orientations are acceptable.
See the dimensional details below for the mounting hole positions.
-Spigot diameters are 125mm
Cover removal slots.

5
i. Base mounted Installation with ducting radiating out horizontally.
ii. Vertically mounted Installation with the exhaust spigot at top. The electrical connections must
come out of the bottom of the unit in order to maintain the water ingress protection.
iii. Ceiling mounted Installation with ducting radiating out horizontally.

6
WIRING
WARNING:
THE UNIT AND ANCILLARY CONTROL EQUIPMENT MUST BE ISOLATED
FROM THE POWER SUPPLY DURING THE INSTALLATION / OR
MAINTENANCE. THIS UNIT MUST BE EARTHED.
1. To remove the cover, use a coin or similar; depress the retaining tabs via the slots in the side of
the unit. There is some kind of weird off-set on this bullet point?
2. With the power off, connect a suitable mains power cable from a switched, fused spur to the screw
terminal block. Use the cable clamps and clip provided to secure the lead.
3. Two mains voltage Live Switched (LS1 and LS2) connections are provided, and can be used to
trigger a change in speed. Common inputs would be from a bathroom lighting circuit. When
commissioning the unit, a delay on timer and an overrun timer can be selected and adjusted in the
software using the buttons and screen. See Commissioning section on page 7 of this document for
details.
4. The switched live output (230Vac) from any other switch or controller, (such as a simple latching pull
cord or push button switch, humidistat or PIR detector) can be connected to the LS terminal instead
of connecting to a lighting circuit.
5. Important: Use 4-core, low voltage, twisted pair, telecoms type cable for accessories (Vent-Axia part
number 459931). Accessories are connected via the IO (Input Output) PCB; see the Low Voltage
Connections diagram. Use the cable clamp and grommet provided.
6. There are no delay on or overrun timers with the volt-free connection as the controller should
determine when the fan is running at Boost or Normal speeds. Use the LS connection described
above if you want a timer.
7. If a humidity sensor is fitted, the unit uses Ambient Response technology to adjust the fan speed
proportionally depending on the temperature and relative humidity levels in the extracted air. The
unit does not just look for relative humidity levels above a set point, which can be unreliable in
products that extract from multiple rooms, but it also looks for rapid increase in relative humidity
typically generated by such activities as showering or cooking. The sensor control also avoids
nuisance tripping at night time when temperatures drop and relative humidity naturally rises.

7
CONNECTION DIAGRAM
A
A
B
B
Main power
connections
Main power
connections
MVDC-MS & MVDC-MSH:
SMV & SMV PLUS:
Low voltage
connections
Low voltage
connections

8
A: Main power connections
The LS1, LS2 and NS terminals are
electrically isolated. If the LS connections
are used, a connection must be made
with the NS terminal. This can be via a
jumper or dedicated neutral connection.
This appliance incorporates an earth connection for functional purposes only.
B: Low voltage connections
For best performance use 4-core,
low voltage, twisted pair, telecoms type
cable for accessories
(available from Vent-Axia part number 459931).
Position
Label
Description
Action
A
RS485
5V
5V Output, Max 250mA
RS485 communication to wired
accessories.
Data connection is only available for SMV/SMV Plus units.
The 5V and Ground connections are available on all units.
B
A+
Data
C
B-
Data
D
GND
Ground
E
D IN 2
COM
Digital input common
Go to Boost speed (Min.1V, max. 6V).
The 5V output from the RS485 connection can be used as
a power supply
F
+
Digital input 2
G
D IN 1
COM
Digital input common
Go to Low speed (Min.1V, max. 6V).
The 5V output from the RS485 connection can be used as
a power supply
H
+
Digital input 1
I
D OUT
2
COM
Digital output common
Unpowered Boost indicator Switch
(switching 6V 50mA max)
J
+
Digital output 2
K
D OUT
1
COM
Digital output common
Unpowered LED fault indicator switch
(switching 6V 50mA max)
L
+
Digital output 1
M
AN 2
+
Analog input 2
0-10V analogue input.
Two user settable voltage thresholds with two user settable
actions. The unit will run at Normal when supplied voltage is
between the two thresholds.
N
GND
Ground
O
AN 1
+
Analog input 1
P
GND
Ground
Connection
Description
1
L
Live (220-240Vac)
2
N
Neutral
3
Functional Earth
4
LS1
Live Switched 1, (220-240Vac), isolated
5
LS2
Live Switched 2 (220-240Vac), isolated
6
NS
Neutral Switched, isolated
A
P
D
E
L
M
1
2
3
5
4
6

9
COMMISSIONING
Advanced feature descriptions
If compatible, the unit can be controlled via the Bluetooth linked App. This is only available on Xunits.
Comfort mode
If Comfort mode is enabled the unit will behave as follows to all LS inputs:
Trigger
Action
LS input active less than 5 minutes
No action
LS input active more than 5 minutes but less
than 20 minutes
Once LS input is removed, fan will run at user
selected speed for the length of time LS was
present plus the set over-run time (if over run is
enabled).
LS input active more the 20 minutes
Unit will Boost after 20mins.
Once LS input is removed, fan will run at user
selected speed for 20 minutes plus the set over-
run time (if over run is enabled).
The above applies to all LS inputs. The times are not adjustable by the user.
Humidity –Rapid rise
Rapid Rise humidity response functions to detect rapid rises in humidity when the ambient %RH is under the threshold
setting. If a rapid rise is detected the fan will boost until the humidity lowers again.
Humidity –Ambient response
When ambient response is enabled the threshold set point is modified based on the ambient temperature. This helps
to prevent nuisance boosting of the unit as temperatures changes during the day.
Analogue inputs
Both analogue inputs have adjustable low and high trigger voltages within the 0-10V range.
The response to being above or below either of the threshold voltages is user settable.
The display doesn’t show a decimal point, for example at threshold voltage of 5.2V, is displayed as “52” on
the unit.
Unit adjustment
1. Commissioning and configuration on all products is supported by the 3 digit user interface and
associated push buttons.
2. When powered on, the unit will display the firmware revision number, after a few seconds the unit
will display the first option in the menu structure (see below).
3. Changes to the settings can be made
via the +and –buttons, the Menu button will
accept changes and move onto the next menu option.
4. When setting the speeds, there is an internal logic: low<Normal<Boost<Purge.
I.e., Boost is always higher than Normal.
5. The actions for each of the Live Switched (LS), inputs are selectable. The setting for delays and
over run timers are applicable to all inputs.

10
User Configurable Parameters
Display
text
Function
Selections
Default
Lxx
Low speed
1 to 97% motor speed
10%
nxx
Normal speed
2 to 98% motor speed
35%
bxx
Boost speed
3 to 99% motor speed
70%
Pxx
Purge Speed
4 to 100% motor speed
100%
LS1
Live switch 1
Low, Boost or Purge speed
Low
LS2
Live switch 2
Low, Boost or Purge speed
Boost
LS3
Live switch 1&2
Low, Boost or Purge speed
Purge
c-n
Comfort mode
Comfort mode - yes or no
No
d-n
Delay On
Delay on - yes or no
No
dxx
Delay On time
Delay to boost duration 1 to 60 minutes
10m
o-n
Overrun
Overrun - yes or no
No
oxx
Overrun time
Overrun duration 1 to 60 minutes
10m
r-n
Humidity –Rapid Rise
Rapid rise - yes or no
Yes
A-n
Humidity –Ambient Response
Ambient response - yes or no
No
hxx
Humidity threshold
Ambient response threshold 40 to 80% RH
70%
C2b
CO2 threshold boost
Boost threshold 1000 –1500 PPM
in increments of 100
1000
C2P
CO2 threshold purge
Purge threshold 1400 –1800 PPM
in increments of 100
1500
A1LA
Analogue 1 - low action
Low, Normal, Boost or Purge speed
Low
A1HA
Analogue 1 - high action
Low, Normal, Boost or Purge speed
Purge
A1tL
Analogue 1 - low threshold
Analogue Input Threshold Low 1 - 99
15
A1tH
Analogue 1 - high threshold
Analogue Input Threshold High 1 - 99
75
A2LA
Analogue 2 - low action
Low, Normal, Boost or Purge speeds
Low
A2HA
Analogue 2 - high action
Low, Normal, Boost or Purge speeds
Purge
A2tL
Analogue 2 - low threshold
Analogue Input Threshold Low 1 - 99
15
A2tH
Analogue 2 - high threshold
Analogue Input Threshold High 1 - 99
75
D1
Digital input 1 Action
Low, Boost or Purge speeds
Low
D2
Digital input 2 Action
Low, Boost or Purge speeds
Purge
unl
Unlock code
Turn on/off the menu lock
- - -
PIn
Display Pin
3 characters A to 9
LoC
dtxx
Display time
Adjust how long the display is illuminated
30 s
rot
Rotate display
Invert the display
rot
hu
Humidity
Show the current internal humidity
%
tu
temperature
Show the current internal temperature
°C
CO2
CO2
Show the current CO2 level
PPM
end
end
End of menu (loop to start)
If the unit being commissioned is not fitted with the relevant hardware, the associated menu options will not
be available.