Fermax 3431 Universal 4+N Intercom Handset – VEO Telephone

The Fermax 3431 is an audio intercom handset for homes wired on a 4+N conventional system — the analogue wiring standard widely used in UK and European residential blocks, where four shared cables run throughout the building alongside one dedicated call wire per dwelling, allowing the outdoor entrance panel to ring the correct flat. Designed for wall-mounted installation in apartments and houses, it connects to the outdoor panel so residents can speak with visitors and release the door remotely.

What makes the 3431 the "Universal" model is its ability to replace handsets from most other brands, not just Fermax — including both buzzer-type and electronic call tone units, as well as older Fermax models. An equivalence table is included in the box to help match the wiring of whatever handset it replaces. The 3431 also operates on both 12 Vac (pure audio 4+N systems) and 18 Vdc (VEO video systems where this handset takes the audio-only role), making it compatible across a wider range of 4+N installations.

Built from high-impact ABS plastic with a UV-resistant, easy-clean textured finish, the handset is designed to last. A magnetic cradle holds the arm securely to the base, preventing accidental disconnection and wall scuffing. Audio levels for both earpiece and microphone can be calibrated by an installer via internal trimmer potentiometers. A built-in inductive loop makes it compatible with hearing aids on the T-setting.

Key Features:

• For 4+N conventional analogue intercom systems (12 Vac audio / 18 Vdc VEO)
• Replaces most analogue handsets — buzzer or electronic, including older Fermax models
• Wiring equivalence table included for cross-brand replacement
• Configurable for electronic call tone or buzzer, and common or separate mass wiring
• Magnetic handset cradle — keeps arm securely docked, protects wall finish
• Built-in inductive loop — hearing aid compatible on T-setting
• One-touch door release button
• White ABS with UV-resistant finish | 214 × 82 × 43 mm | 0.30 kg

Frequently Asked Questions:

Will the Fermax 3431 replace my existing intercom handset?
The 3431 replaces most analogue 4+N intercom handsets, including models from other brands and older Fermax units. A wiring equivalence table is included to match your existing connections. It is not compatible with digital or 2-wire bus systems such as Fermax DUOX or PLUS — if you are unsure, check whether your wiring has four shared cables plus one individual call wire per flat.

Can I fit the Fermax 3431 myself, or do I need an installer?
The unit connects to your existing wiring using the enclosed equivalence table. Correct configuration of the call tone type and mass wiring jumpers is required during installation. If you are comfortable with matching wired connections, this is a manageable DIY job; if you are unfamiliar with intercom wiring, a qualified installer is recommended.