ENGO E40-230W is a 230V AC wired ZigBee 3.0 / 868MHz smart thermostat, built for installers who want a mains-powered controller without the wiring complexity of a hard-wired relay system. It shares its wireless architecture and up-to-6-valve radiator control with the battery-powered E40-BAT, but takes its power directly from the 230V supply rather than from batteries, making it a good fit for permanent installations where a mains feed is already available. The compact 80 x 80 x 22mm surface-mounted body and clear LCD display keep the finished installation neat and easy to read. Available in white.
Up to 6
Radiator valves controlled
Mains wiring must be carried out by a qualified electrician
This thermostat is powered directly from the 230V AC mains supply. Installation and wiring must be carried out by a person with appropriate electrical qualifications, in accordance with the wiring regulations in force in the country of installation (including BS 7671 in the UK).
ZigBee gateway required for full remote control
As with the rest of the ENGO Smart ecosystem, remote scheduling and app control via ENGO Smart requires a compatible ZigBee gateway, purchased separately. Local operation, scheduling, and ENGO binding to receivers or valve heads do not require a gateway.
Key Features
Mains-powered with no batteries to replace
Taking its supply directly from 230V AC means there are no batteries to monitor or replace over the life of the installation, which suits permanent fixed installations better than a battery unit.
Controls up to six radiator valves from one thermostat
A single E40-230 can command up to six electronic radiator valve heads over the 868MHz link, giving one thermostat control over every radiator in a larger or open-plan room.
Volt-free COM/NO output for flexible wiring
The thermostat's control output is a potential-free COM/NO relay with a configurable relay type, so installers can adapt it to different boiler, pump, or actuator control circuits without additional interface hardware.
TPI, hysteresis and Delta RCWC control algorithms
Temperature is held using a TPI algorithm, adjustable hysteresis (±0.2°C to ±2°C), or Delta RCWC, letting the installer match the control behaviour to the heat emitter and building fabric.
Works offline as well as with the ENGO Smart app
Time schedules are stored on the thermostat and continue to run without an internet connection, with remote access and app control available once a ZigBee gateway is added to the system.
Compact, surface-mounted 22mm-deep body
The 80 x 80 x 22mm enclosure mounts straight to the wall surface without chasing in a back box, keeping installation quick on both new builds and retrofit radiator or underfloor heating jobs.
Technical Specification
| Power & Switching |
| Power supply |
230V AC, 50Hz |
| Max. load |
3(1)A |
| Control output |
COM/NO, voltage free |
| Temperature Control |
| Setpoint range |
5.0°C to 45.0°C |
| Display accuracy |
0.5°C |
| Control algorithm |
TPI, hysteresis (±0.2°C to ±2°C), Delta RCWC |
| Connectivity |
| Communication |
ZigBee 3.0, Radio 868MHz |
| Radiator valve support |
Up to 6 electronic radiator valve heads |
| App platform |
ENGO Smart (ZigBee gateway required for remote/app control) |
| Physical |
| Dimensions |
80 x 80 x 22mm |
| Mounting |
Surface-mounted |
| Colour |
white |
Frequently Asked Questions
Does this thermostat need a gateway to work?
No gateway is required for local scheduling and ENGO binding to receivers or radiator valves. A ZigBee gateway is needed for remote control and app scheduling via ENGO Smart.
How many radiator valves can one E40-230 control?
Up to six electronic radiator valve heads can be linked to a single E40-230, allowing one thermostat to manage every radiator in a room.
Is this thermostat suitable for underfloor heating as well as radiators?
Yes, the E40-230 is compatible with both underfloor heating and radiator heating systems via the appropriate ENGO receiver or valve head.
What is the maximum load the relay can switch?
The volt-free COM/NO output is rated to 3(1)A. For higher-current loads such as electric heating mats, an external contactor or the higher-rated EONE-16 thermostat should be used instead.
Can the schedule still run if the internet or gateway goes down?
Yes. Time schedules are stored on the thermostat itself and continue to run in offline mode without an active internet or gateway connection.
