Vent-Axia Lo-Carbon MVDC & Sentinel Multivent Range

Product Overview

The Vent-Axia Lo-Carbon MVDC and Sentinel Multivent units are designed for simultaneous extract ventilation of multiple wet rooms, such as bathrooms, kitchens, and toilets. These units feature a highly efficient backward-curved centrifugal motor impeller set and are designed for continuous 24-hour operation.

Depending on the model, units offer either 3 or 4 settable speeds and can be configured to change speed based on various sensor or control inputs. X-Units incorporate wireless controls and Bluetooth capability.

Model Range and Stock References

App Availability

Download the Vent-Axia app from the App Store or Google Play to manage your unit.

⚠ PLEASE READ THESE INSTRUCTIONS CAREFULLY BEFORE COMMENCING INSTALLATION OR OPERATION.

PLEASE RETAIN THESE INSTRUCTIONS WITH THE PRODUCT.

Important Safety Information

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 IET 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.
• Units showing [Earth Symbol] on the rating label incorporate an earth connection for functional purposes only.
• Units showing [Protective Earth Symbol] on the rating label have a Protective Earth.
• Precautions must be taken to avoid the backflow 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 in accordance with building regulation and be at least 300mm away from any flue outlet.
• This product and associated duct installation should be carried out in accordance with the Domestic Ventilation Compliance Guide.

Radio and Bluetooth Communication

Models supporting Radio and Bluetooth communication:

• Bluetooth variants contain FCC ID: S9NSPBTLERF
• Bluetooth LE: -12dBm EIRP (63µW), nominal 2450MHz.
• Bluetooth v4.1 compliant.
• Bluetooth and radio variants obtained RED certificate: No. 0051-RED-0011 REV. 0.
• Zirconia Wireless: -14dBm EIRP nominal 868MHz.
• The manufacturer assures 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: https://www.vent-axia.com/range/centralised-mechanical-extract-ventilation-mev

Model Specifications Comparison

The units can be precisely programmed to respond to changes in sensor values or signal inputs. They operate at a normal flowrate until a sensor or input change triggers a speed adjustment. Switched Live and Digital inputs cause a step change, while Analogue, Humidity, and CO2 sensors can provide a proportional response.

Installation

Position the unit considering room layout, exhaust location, and electrical services, ensuring adequate access for installation and maintenance.

A condensate drain is generally not necessary if the unit is sited in a heated void. In cold voids, consider fitting a drain or externally insulating the unit and ducting to minimize condensation.

Duct System Guidelines

To reduce system resistance, lower speed, power consumption, and noise, follow these guidelines:

1. Keep duct runs to a minimum, especially the exhaust duct.
2. If using flexible ducting, ensure it is fully extended, not crushed, sagging, or torn.
3. Minimize diffusers/valves by using similar length duct runs to the inlets.
4. Ensure bend radius (measured to the inside) is at least 1x the duct diameter.
5. Avoid bends, filters, or obstructions within 250mm of the fan inlets and outlet.
6. Set valves to their maximally opened positions for minimal pressure drop.

Securely mount the unit using appropriate fixings for the substrate. Anti-vibration mounts, acoustic mat, or rubber bushes are recommended. Fixings must be capable of securing 4 times the unit's weight (4.1kg).

Mounting Orientation

To maintain the IPx2 rating, the unit must NOT be mounted with cover removal slots facing upwards or at an angle visible from above. All other orientations are acceptable.

Dimensional Details

Spigot diameters are 125mm. Detailed mounting hole positions are provided in dimensional drawings.

Installation Types

Illustrations depict three installation types:

• i. Base mounted Installation: Ducting radiates out horizontally.
• ii. Vertically mounted Installation: Exhaust spigot at top. Electrical connections must come from the bottom to maintain water ingress protection.
• iii. Ceiling mounted Installation: Ducting radiates out horizontally.

Wiring

WARNING: THE UNIT AND ANCILLARY CONTROL EQUIPMENT MUST BE ISOLATED FROM THE POWER SUPPLY DURING INSTALLATION / OR MAINTENANCE. THIS UNIT MUST BE EARTHED.

1. To remove the cover, use a coin or similar to depress the retaining tabs via the slots in the side of the unit.
2. With the power off, connect a suitable mains power cable from a switched, fused spur to the screw terminal block. Use the provided cable clamps and clip to secure the lead.
3. Two mains voltage Live Switched (LS1 and LS2) connections are provided and can be used to trigger speed changes. Common inputs are from a bathroom lighting circuit. During commissioning, a delay on timer and an overrun timer can be selected and adjusted in the software using the buttons and screen. Refer to the Commissioning section for details.
4. The switched live output (230Vac) from any other switch or controller (e.g., latching pull cord, push-button switch, humidistat, or PIR detector) can be connected to the LS terminal instead of a lighting circuit.
5. Important: Use 4-core, low voltage, twisted pair, telecoms type cable (Vent-Axia part number 459931) for accessories. Accessories connect via the IO (Input Output) PCB. Use the cable clamp and grommet provided.
6. Volt-free connections do not have delay-on or overrun timers; the controller must determine boost or normal speeds. Use the LS connection for timer functionality.
7. Units showing [Earth Symbol] on the rating label incorporate an earth connection for functional purposes only.
8. Units showing [Protective Earth Symbol] on the rating label have a Protective Earth.

Connection Diagram

A: Main power connections

The LS1, LS2, and NS terminals are electrically isolated. Note: Remove the neutral link between terminals 2 and 6 if different RCD protection circuits are used for mains power and Live Switch connections. Ensure all live and neutral connections are isolated before servicing.

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).

Terminal Descriptions (Main Power)

A diagram illustrates the main power connections and a simplified wiring schematic for low voltage connections.

Terminal Functions and RS485 Inputs

Terminal Functions

RS485 Wired Inputs

RS485 terminals connect compatible sensors and switches, allowing daisy-chained wiring. Maximum cable length is 250m. Accessories must be paired to the unit to function.

A diagram illustrates RS485 wired input connections for a single slave device and multiple slave devices, showing sensor connections and termination jumpers.

Wireless Inputs and Sensor Management

RF868 Wireless Inputs

Units with a Wireless receiver can be paired with mains or battery-powered sensors. A maximum of 15 wired and wireless sensors can be connected per unit.

Pairing Sensors

To pair a sensor:

• Press the 'Mode' button to turn on the display.
• Press and hold 'Mode' until the LED illuminates solid White.
• Release 'Mode'; the LED will flash White, indicating pairing mode. The unit stays in pairing mode for 1 hour or until 'Mode' is pressed again.
• Activate the pairing function on the sensor (refer to sensor's instructions).
• The number of paired devices is displayed upon successful pairing.

Removing Sensors

To remove paired sensors, the unit must be reset (this resets all values to factory default):

• Press 'Mode' to turn on the display.
• Press and hold 'Mode' until the LED illuminates solid Red.
• Release 'Mode'; the LED will stay Red.
• Pressing 'Mode' again confirms the reset. If no reset is desired, wait for the command to time out.

Sensor Priorities

The unit sets motor speed based on the following priority order:

• User override
• LS inputs (1 and 2)
• Digital inputs (1 and 2)
• Sensor override (Humidity, CO2, Analogue inputs, based on highest speed setting)
• Default speed (normal operation)

If multiple inputs are active, the motor runs at a speed determined by the input with the highest priority level.

Example connection diagrams for LED Fault Indicator and LED Boost Indicator are provided, noting that MVDC MS/H models do not have these facilities.

Feature Descriptions

Units can be controlled via the Bluetooth linked App (available on Sentinel-X Wireless units).

Comfort Mode

When Comfort mode is enabled, unit behaviour based on LS inputs:

Times are not adjustable by the user.

Delay On

A delay can be set so the unit does not respond to an input until the set delay has elapsed. Applies to LS inputs only.

Overrun Timer

The unit can be set to run for a defined period after the input is removed. Applies to LS inputs only.

Humidity Sensing

• Rapid Rise*: Detects rapid rises in humidity when ambient %RH is below the threshold. The fan boosts until humidity lowers.
• Ambient Response*: Threshold set point is modified based on ambient temperature to prevent nuisance boosting due to temperature changes.
• Threshold*: The unit boosts when RH is above the threshold set point.

CO2 Threshold Boost / Purge*

The unit enters Boost / Purge mode when detected CO2 levels exceed set thresholds.

Analogue Inputs

Both analogue inputs have adjustable low and high trigger voltages (0-10V range). Response to being above or below thresholds is user-settable. Note: The display shows '52' for 5.2V.

Digital Inputs

The unit can change speed based on whether digital inputs are above or below the threshold voltage. Refer to Low Voltage Connections table for details.

Display Lock

A pin code can be enabled via the main menu to protect settings. The 3-digit pin uses characters A-F and 0-9; the default is 'LoC'.

External RH or CO2 sensors fitted via RS485 have priority over internal sensors and their values are displayed preferentially.

Unit Adjustment and Calibration

Unit Adjustment

1. Commissioning and configuration use a 3-digit user interface and push buttons.
2. On power-up, the unit displays firmware revision, then the first menu option.
3. The display enters standby after a timeout (default 10 min) or when 'END' is selected. Press 'Mode' to reactivate.
4. Settings are changed using '+' and '-' buttons; 'Mode' accepts changes and moves to the next option.
5. Speed settings follow logic: Low<Normal<Boost<Purge.
6. Actions for Live Switched (LS) inputs are selectable. Delay and overrun timer settings apply to all inputs.
7. To restore factory settings, press and hold 'Mode' for 10 seconds.

Bluetooth Pairing

To enable Bluetooth pairing:

• Press 'Mode' to turn on the display.
• Press and hold 'Mode' until the LED illuminates solid Blue.
• Release 'Mode'; the LED will flash Blue, indicating pairing mode.
• Follow the on-app instructions to connect.

A screenshot of the Vent-Axia mobile app's welcome screen is shown.

User Configurable Parameters

The following table lists user-configurable parameters:

If the unit is not fitted with relevant hardware, associated menu options may not be available.

CO2 Calibrations

Instructions for calibrating internal and room sensors:

MEV Unit - Internal Sensor Calibration

Step 1: Exposure or Measurement Method

• Exposure Method: Assumes outside CO2 is 400 PPM. Rooms must be well-ventilated (open windows/doors for 10-15 min) and remain unoccupied until baseline is actioned.
• Measurement Method: Use a calibrated CO2 meter to measure CO2 in rooms, record, and average the values. Example: (Room 1: 450ppm + Room 2: 440ppm + Room 3: 460ppm) / 3 = 450ppm.

Step 2: Baseline Adjustment

• On-Board Display: Navigate to 'rEF' menu. Default is 40 (=400ppm). For Measurement Method, change 'rEF' to the recorded average PPM (e.g., 45 for 450ppm). Navigate to 'cAL' and select 'y' (Yes). Status LED blinks Magenta during calibration (approx. 3 min).
• Mobile App: Connect to the unit, navigate to the CO2 screen, and enable 'Set CO2 calibration'. Adjust the slide bar to match the measured average PPM (e.g., 450ppm). For Exposure Method, keep default 400ppm. Press 'Save'. Status LED blinks Magenta during calibration (approx. 3 min).

Room Sensor Calibration

Room sensors use Exposure method and Auto Background Calibration (ABC) by default.

Step 1: Exposure Method

Assumes outside CO2 is 400 PPM. Room must be well-ventilated (open windows/doors for 10-15 min) and remain unoccupied until baseline is complete.

Step 2: Baseline Method

With the Room sensor paired, press and hold the button until the status LED turns Magenta (approx. 8 seconds). Release the button; the LED will blink Magenta. The room must remain unoccupied for 5 minutes while the sensor calibrates.

Fault Codes and Spare Parts

Fault Codes

If the unit detects a fault, an error message is displayed on the HMI:

If a fault persists, contact local technical support.

Spare Parts

WARNING: THE FAN AND ANCILLARY CONTROL EQUIPMENT MUST BE ISOLATED FROM THE POWER SUPPLY DURING PART REPLACEMENT.

1. Individual faulty parts should not be replaced due to assembly complexity; only the full scroll assembly is replaceable.
2. To remove the scroll assembly, isolate power, depress cover retention clips with a coin or similar, and remove the cover.
3. Disconnect and remove power supply and signal leads.
4. Remove the scroll assembly by unscrewing two screws and unclipping clips in opposite corners, then lift the assembly out.
5. The fan has sealed-for-life bearings and requires no lubrication. Expected service life is at least 45,000 hours of continuous running.
6. Upon reassembly, check all fixings are tight and secure.

For replacement Scroll assembly, contact Vent-Axia Technical Support: +44 (0)344 856 0594 or vatechsupport@vent-axia.com. Note the model name and number for correct part supply.

Accessories

The following tables list available accessories for different models and general accessories:

Model-Specific Accessories

General Accessories (All units)

Product Fiche

Technical specifications for various models:

Disposal and Guarantee

Disposal

This product should not be disposed of with household waste. Please recycle where facilities exist. Check with your local authority for recycling advice.

The Vent-Axia 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 products for two years from date of purchase against faulty material or workmanship. Provided the product:

• Has been installed and used in accordance with the instructions.
• Has not been connected to an unsuitable electricity supply.
• Has not been subjected to misuse, neglect, or damage.
• Has not been modified or repaired by an unauthorized person.

IF CLAIMING UNDER TERMS OF GUARANTEE: Return the complete product, carriage paid, to your original supplier or nearest Vent-Axia Centre. Include a letter stating the nature of the fault and evidence of purchase date and source. The guarantee is an extra benefit and does not affect legal rights.

Contact Information

Head Office: Fleming Way, Crawley, West Sussex, RH10 9YX

EU Authorised Representative: Vent-Axia Sigarenmaker 5 - 5521DJ Eersel Nederland (authorisedrep@vent-axia.nl)

UK NATIONAL CALL CENTRE:

• Sales Enquiries: Tel: 0344 8560590, Email: sales@vent-axia.com
• Technical Support: Tel: 0344 8560594, Email: vatechsupport@vent-axia.com

Ventair Australia:

• Tel: +61 3 9775 0556, Fax: +61 39775 0775, Email: info@ventair.com.au
• 4 Capital Place, Carrum Downs, VIC 3201, Australia

Vent-Axia reserves the right to alter specifications without notice as part of its continuous product improvement policy.