Somfy J4 HTM / WT / RTS / io – Venetian Blind & External Louvre Motor (used & refurbished | tested)
“I am the motor that guides every ray of light – precise, quiet and weather-resistant, ensuring your blinds always move perfectly.”
I offer used Somfy J4 motors for venetian blinds and external louvre systems – the professional drive solution for façade shading and outdoor blind systems.
The J4 series from Somfy stands for precision, smooth operation and durability – engineered to position slats accurately, respond to wind and sunlight, and operate reliably even in demanding weather conditions.
The motors are available in different control versions:
 
 
J4 HTM: classic mechanical drive for simple switch controls – ideal for standard installations.
 
 
J4 WT: wired version for group or central controls with automatic functions.
 
 
J4 RTS: radio motor with proven Radio Technology Somfy – wireless, low-interference, perfect for retrofitting.
 
 
J4 io: latest generation with io-homecontrol® – bidirectional, smart-home compatible, with status feedback and perfect integration into central control systems.

The optional Protect versions (J4 WT Protect / io Protect) feature integrated blockage detection and frost protection, allowing the slats to stop automatically in case of resistance or ice formation – ensuring long-term protection and functionality.
 
Inspection and refurbishment in a certified workshop
 
 
Function and running behavior
 
 
Mechanical end-stop adjustment and rotation direction
 
 
Electrical safety according to GPSR
 
 
Condition of the power cable and mechanical coupling

Worn parts are replaced where necessary, ensuring the motor is technically tested and ready for immediate use.
 
Application: External venetian blinds & façade shading
The Somfy J4 series is designed specifically for external venetian blinds, façade shading and louvre systems.
Thanks to precise slat positioning, these motors allow fine control of light and shade.
Depending on the model, they can be integrated into single, group or radio control systems and support automatic operation with sun, wind and weather sensors.
The Protect versions provide additional overload and freeze protection, making them ideal for large or exposed installations on weather-facing façades.
 
Sustainability meets safety
Professional refurbishment extends the lifespan of these high-quality motors – a sustainable alternative to replacement.
All motors are tested according to the EU safety regulation (GPSR) and meet current standards for operational safety.
Each motor originates from trusted sources or from my own stock and is only resold after a successful functional test.
 
Additional Notes
 
 
The product images provided are for reference only. Nameplates or housing details may differ, as Somfy has adjusted its serial markings over the years. The exact motor type is always stated in the respective variant description.
 
 
The motors are supplied without accessories; a cable with STAS3 connector is usually installed on block motors. If you need adapters, shaft couplings or control cables, you can order them separately (if available) or contact me directly.
 
 
Cable types:
 Newer models feature a detachable connection cable.
 Older versions typically include a fixed, sufficiently long cable.
 
 
A user manual is usually provided after purchase.

 
Legal Compliance & Quality
 
 
Tested according to EU Safety Regulation (GPSR)
 
 
VAT: Differential taxation according to § 25a UStG (no VAT shown)
 
 
Warranty: 1 year provided by Smart Home Thomas Reh
 
 
Island shipping: Flat surcharge of €27 for deliveries to the following European islands: Canary Islands, Madeira, Azores, Balearic Islands, Corsica, Sardinia, Sicily, Greek islands, and German North Sea/Baltic Sea islands.
 
 
Regular expansion: I continuously receive additional used Somfy block motors, which are added to the shop after inspection.

 
Advantages at a glance
 
 
J4 HTM: Mechanical basic version for standard controls
 
 
J4 WT: Wired version for central & group systems
 
 
J4 RTS: Wireless motor with proven RTS technology
 
 
J4 io: Smart-home ready via io-homecontrol® with status feedback
 
 
Protect versions: Blockage detection & frost protection
 
 
Tested in a certified workshop
 
 
Legally compliant according to GPSR