Vent-Axia 403835 Lo-Carbon Tempra SELV LT Heat Recovery Unit Longer Cell & Timer
Vent-Axia 403835 Lo-Carbon Tempra SELV LT Heat Recovery Unit – Long Cell with Timer
The Vent-Axia 403835 Lo-Carbon Tempra SELV LT Heat Recovery Unit is a compact, energy-efficient through-the-wall ventilation system designed to improve indoor air quality while reducing heat loss. Featuring Safety Extra Low Voltage (SELV) operation, a 460mm long cell and an overrun timer, this decentralised mechanical ventilation with heat recovery (dMVHR) unit is ideal for bathrooms, kitchens, toilets and utility rooms in residential properties and social housing.
Designed to fit an existing 100mm diameter wall opening, the Tempra SELV LT provides an effective upgrade from conventional extractor fans. Its integrated heat exchanger achieves up to 78% temperature efficiency, recovering warmth from extracted air to help maintain comfortable indoor temperatures and reduce energy consumption.
Key Features
- SELV Design: Safety Extra Low Voltage configuration for installations requiring extra-low-voltage ventilation equipment.
- Overrun Timer: Timer-controlled ventilation allows extraction to continue after activation, helping remove residual moisture and stale air.
- Heat Recovery Efficiency: Recovers up to 78% of heat from outgoing air to help minimise heat loss.
- Extended 460mm Cell: Suitable for external wall thicknesses between 321mm and 460mm.
- Continuous Ventilation: Selectable extraction rates of 6 l/s or 9 l/s, with boost extraction up to 15 l/s.
- Energy-Efficient Motor: Lo-Carbon EC/DC motor consumes as little as 3.2W at trickle speed.
- Quiet Operation: Low-noise performance of approximately 20dB(A) at the lowest operating setting.
- 100mm Wall Installation: Compact design fits standard 100mm diameter wall openings.
- Summer Extract Mode: Manual extract-only setting helps prevent unwanted heat recovery during warmer weather.
- IPX4 Rated: Splash-resistant design for suitable bathroom and utility room installations.
- Easy Maintenance: Accessible heat exchanger simplifies routine cleaning and servicing.
Energy-Efficient Heat Recovery Ventilation
The Vent-Axia Lo-Carbon Tempra SELV LT uses an integrated heat exchanger to recover heat from outgoing stale air and transfer it to incoming fresh air. With temperature efficiency of up to 78%, the system helps reduce ventilation-related heat loss while maintaining a consistent supply of fresh air.
The unit can be configured for continuous extraction at 6 l/s or 9 l/s, with a boost rate of 15 l/s when increased ventilation is required. For intermittent extraction applications, the unit can operate at 15 l/s.
Its airflow arrangement maintains slight negative pressure within the ventilated room, helping prevent humid air from spreading into adjoining areas. This makes it particularly useful for controlling condensation and moisture in bathrooms, kitchens and utility rooms.
Convenient Timer-Controlled Ventilation
The integrated overrun timer allows the Vent-Axia 403835 to continue extracting air after the activation signal has ended. This provides additional ventilation to help remove lingering moisture, odours and stale air, making the unit particularly practical for bathrooms and toilets.
Combined with its SELV design, the timer-equipped configuration provides an efficient ventilation solution for suitable domestic and refurbishment applications.
Low-Energy and Quiet Performance
Equipped with a high-efficiency Lo-Carbon EC/DC motor and twin impellers, the Tempra SELV LT consumes as little as 3.2 watts at its lowest continuous extraction setting. This low-energy operation makes it suitable for applications requiring regular or continuous ventilation.
Operating at sound levels as low as 20dB(A), the unit delivers discreet ventilation while helping maintain a comfortable indoor environment.
Ideal Applications
- Bathrooms and shower rooms
- Toilets and WC facilities
- Domestic kitchens requiring extract ventilation
- Utility rooms and laundry areas
- Social housing and residential developments
- Property refurbishment and renovation projects
- Replacement of existing 100mm wall-mounted extractor fans
- Installations requiring SELV ventilation with timer control
Technical Specifications
- Manufacturer: Vent-Axia
- Product Code: 403835
- Product Range: Lo-Carbon Tempra
- Model: SELV LT – Long Cell with Timer
- Ventilation Type: Decentralised Mechanical Ventilation with Heat Recovery (dMVHR)
- Electrical Design: Safety Extra Low Voltage (SELV)
- Installation Type: Through-the-wall
- Duct Connection Size: 100mm diameter
- Long Cell Length: 460mm
- Suitable Wall Thickness: 321–460mm
- Heat Recovery Efficiency: Up to 78%
- Continuous Extraction Rate: 6 l/s or 9 l/s
- Boost Extraction Rate: 15 l/s
- Minimum Power Consumption: 3.2W
- Noise Level: As low as 20dB(A)
- Motor Type: Lo-Carbon EC/DC with twin impellers
- Control Type: Overrun timer
- Summer Mode: Manual extract-only operation
- IP Rating: IPX4
- Applications: Bathrooms, kitchens, toilets and utility rooms
Simple Installation and Maintenance
The Vent-Axia 403835 Tempra SELV LT is designed for installation through an external wall using a standard 100mm diameter opening. Its extended 460mm cell accommodates wall thicknesses from 321mm to 460mm, making it particularly suitable for properties with thicker external walls.
The compact heat exchanger design allows the unit to replace many traditional 100mm extractor fans while providing the additional benefits of heat recovery ventilation. Its straightforward construction and accessible heat exchanger also simplify routine maintenance.
Installation should be carried out in accordance with the manufacturer's instructions and applicable electrical and building regulations, particularly where SELV equipment is required.