Vent-Axia Sentinel Multivent SMV Instructions De Montage Et De Câblage page 5

4.1. To reduce the system resistance in your duct system, and therefore lower the speed, power consumption and
noise of the fan, follow these instructions:
4.1.1. Keep the length of duct runs to a minimum, particularly the exhaust duct run.
4.1.2. Use larger diameter ducting rather than smaller.
4.1.3. If you need to use flexible ducting, make sure that it is fully extended and not crushed, sagging or torn.
4.1.4. Try to minimise the use of dampers by having similar length duct runs to the inlets.
4.1.5. The bend radius, (measured to the inside of the bend), should be at least 1x the duct diameter. The larger
the better.
4.1.6. Avoid having any bends, filters or other obstructions within 250mm of the fan inlets and outlet.
4.2. Mark out the fixing positions and drill holes. Use wall plugs if appropriate. Screw the fan housing in place.
4.3. Ducting passing through an unheated space should be insulated. The Sentinel Multivent can be connected to
either ø125mm or ø100mm ducting. Remove the blanking caps to connect ø125mm ducting. To connect ø100mm
ducting, peel out the centre of the cap with a screwdriver as indicated on the cap and leave the cap surround in
position. To connect ducting to the base intake, remove the round pieces of foam and fit the cap provided in the
hole. Securely connect ducting to the spigots using worm-drive clips, cable ties or duct tape.
5. Wiring to the Sentinel Multivent
5.1. Remove the cover by undoing the four screws and pulling it away.
5.2. With the power off, connect a suitable mains power cable from a switched, fused spur to the power supply PCB.
For your convenience, a plug is provided. Remove this from the power supply PCB and connect the mains cable to
its terminals. Then plug it back in to the power supply PCB. Use the cable clamps and clip provided to secure the
lead.
5.3. If you want the fan to switch to boost speed when a light is turned on, connect the switched live connection from
the lighting circuit to the LS connection on the power supply board. 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.
5.4. The switched live output (230V) from any other switch or controller, (such as a simple pullcord or push button
switch, humidistat or PIR detector) can be connected to the LS terminal instead of connecting to a lighting circuit.
5.5. Important: Use 4-core, low voltage, twisted pair, telecoms type cable for accessories (Vent-Axia part number
459931). Connect any outputs from accessories / controls that you want to use to the terminal block on the
motherboard. Again, use the cable clamp provided. Remove the knock out from the cover. The connections for
accessories on the motherboard are powered by a SELV (Safety Extra Low Voltage) power supply.
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