ENGO EHW-W WiFi Hot Water Timer with Built-In Thermostat – Programmable DHW Controller | White
ENGO EHW-W WiFi Hot Water Timer with Built-In Thermostat – Programmable DHW Controller | White
The ENGO EHW-W is a WiFi-enabled programmable hot water timer and thermostat in a clean white finish — designed to put your domestic water heater on a smart schedule. Control it remotely via the ENGO Smart app, programme it to run only during off-peak electricity hours, and rely on the built-in thermostat to maintain your preferred water temperature. Compatible with most electric water heaters and immersion cylinders. No hub needed.
Why Choose the ENGO EHW-W?
Full remote control, scheduling, and monitoring from anywhere via iOS or Android — no hub needed.
Set exactly when the heater runs — avoids wasted energy heating water at times it's not needed.
Monitors and maintains water temperature via an external NTC sensor — no separate thermostat device needed.
2.4 GHz Wi-Fi built into the unit — connects directly to your home network without a gateway.
Programme to run exclusively on Economy 7, Octopus Go, or other cheap-rate overnight electricity tariffs.
S1/COM terminal accepts an NTC temperature sensor or volt-free contact for versatile control options.
Clean white finish matches standard UK switches and sockets — blends seamlessly into any room. Black version (EHW-B) also available.
Programme and operate directly from the display and buttons — no app required for day-to-day use.
Suitable For
About the EHW-W
The EHW-W is the white version of the EHW series — identical in specification and function to the EHW-B, differing only in finish. It mounts on the wall near the water heater and switches the heater's mains supply through its built-in relay according to the set schedule and thermostat temperature.
On Economy 7, Octopus Go, or similar time-of-use tariffs, hot water can cost significantly more to heat during peak daytime hours than overnight. The EHW-W makes it simple to programme the heater to run only during cheap-rate periods — once set up in the app, it runs automatically every day without any manual adjustment.
The built-in thermostat uses an external NTC temperature sensor (connected to S1/COM) to monitor the water or cylinder temperature and switch the heater according to the hysteresis setpoint. The hysteresis band is adjustable between ±1°C and ±20°C — tighter bands maintain temperature more precisely; wider bands allow greater fluctuation for less frequent switching.
The built-in relay is rated 5(2)A. For most standard immersion heaters (3 kW / ~13A), wire the EHW's output to a suitable 16A contactor, with the EHW controlling the contactor coil. The EHW controls the contactor; the contactor switches the heater.
Key Features
- Wi-Fi 2.4 GHz built in — no hub or gateway required
- ENGO Smart app control (iOS & Android, Tuya Cloud)
- Programmable timer — adjustable operating hours
- Built-in thermostat with adjustable hysteresis (±1°C to ±20°C)
- Display accuracy: 0.5°C
- Relay output: NO/COM/NC, rated 5(2)A at 230V
- S1/COM input: NTC temperature sensor or volt-free contact
- 230V AC 50Hz power supply
- Intuitive control panel and clear display
- White finish (see EHW-B for black)
- Compact 90 × 90 × 44 mm housing
- Wall mount installation
Technical Specifications
| Specification | Value |
|---|---|
| Model | EHW-W |
| Colour | White |
| Power Supply | 230V AC / 50Hz |
| Communication | Wi-Fi 2.4 GHz (no hub required) |
| App | ENGO Smart (Tuya Cloud) — iOS & Android |
| Relay Output | NO/COM/NC, 5(2)A at 230V AC |
| Sensor/Input (S1/COM) | NTC temperature sensor or volt-free contact |
| Control Algorithm | Hysteresis (±1°C to ±20°C) |
| Display Accuracy | 0.5°C |
| Dimensions | 90 × 90 × 44 mm |
| Mounting | Wall mount |
Installation Notes
Installation must be carried out by a qualified person per BS 7671. Ensure the relay output rating is appropriate for the connected load.
- Connect 230V L and N to the power supply terminals
- Wire NO/COM output to the heater supply (use external contactor for loads over 5A)
- Connect NTC sensor to S1/COM for thermostat function
- Wi-Fi: 2.4 GHz only — ensure your phone is on the 2.4 GHz band during initial app setup
- Schedule and setpoints can be configured on the device display or via the ENGO Smart app
Frequently Asked Questions
Can this control a standard immersion heater?
Yes, but most immersion heaters draw ~13A which exceeds the relay's 5A rating. Wire the EHW's output to a 16A contactor coil, and let the contactor switch the immersion heater. The EHW controls the contactor; the contactor controls the heater.
Is a separate thermostat needed?
No — the EHW-W has a built-in thermostat. However, it requires an external NTC temperature sensor connected to S1/COM to use the thermostat function. Without the sensor, only timed on/off control is available.
Do I need the ENGO Smart app?
No — the EHW-W can be programmed fully using the onboard display and buttons. The app provides the added convenience of remote access and monitoring.
Is there a black version?
Yes — the EHW-B is identical in specification but finished in matt black. See the EHW-B listing.
Does it work with smart tariffs like Octopus Go?
Yes — programme the timer schedule to match your cheap-rate electricity window and the EHW-W will automatically run the heater only during those hours.
What's in the Box
- 1× EHW-W WiFi hot water timer (white)
- Wall mounting fixings
- Quick installation guide
Note: NTC temperature sensor sold separately. For the black version see EHW-B.
Installation by qualified person per BS 7671. Relay rated 5(2)A — use external contactor for loads exceeding 5A. 2.4 GHz Wi-Fi only. Black version available: EHW-B.
Original: $101.23
-65%$101.23
$35.43More Images
ENGO EHW-W WiFi Hot Water Timer with Built-In Thermostat – Programmable DHW Controller | White
The ENGO EHW-W is a WiFi-enabled programmable hot water timer and thermostat in a clean white finish — designed to put your domestic water heater on a smart schedule. Control it remotely via the ENGO Smart app, programme it to run only during off-peak electricity hours, and rely on the built-in thermostat to maintain your preferred water temperature. Compatible with most electric water heaters and immersion cylinders. No hub needed.
Why Choose the ENGO EHW-W?
Full remote control, scheduling, and monitoring from anywhere via iOS or Android — no hub needed.
Set exactly when the heater runs — avoids wasted energy heating water at times it's not needed.
Monitors and maintains water temperature via an external NTC sensor — no separate thermostat device needed.
2.4 GHz Wi-Fi built into the unit — connects directly to your home network without a gateway.
Programme to run exclusively on Economy 7, Octopus Go, or other cheap-rate overnight electricity tariffs.
S1/COM terminal accepts an NTC temperature sensor or volt-free contact for versatile control options.
Clean white finish matches standard UK switches and sockets — blends seamlessly into any room. Black version (EHW-B) also available.
Programme and operate directly from the display and buttons — no app required for day-to-day use.
Suitable For
About the EHW-W
The EHW-W is the white version of the EHW series — identical in specification and function to the EHW-B, differing only in finish. It mounts on the wall near the water heater and switches the heater's mains supply through its built-in relay according to the set schedule and thermostat temperature.
On Economy 7, Octopus Go, or similar time-of-use tariffs, hot water can cost significantly more to heat during peak daytime hours than overnight. The EHW-W makes it simple to programme the heater to run only during cheap-rate periods — once set up in the app, it runs automatically every day without any manual adjustment.
The built-in thermostat uses an external NTC temperature sensor (connected to S1/COM) to monitor the water or cylinder temperature and switch the heater according to the hysteresis setpoint. The hysteresis band is adjustable between ±1°C and ±20°C — tighter bands maintain temperature more precisely; wider bands allow greater fluctuation for less frequent switching.
The built-in relay is rated 5(2)A. For most standard immersion heaters (3 kW / ~13A), wire the EHW's output to a suitable 16A contactor, with the EHW controlling the contactor coil. The EHW controls the contactor; the contactor switches the heater.
Key Features
- Wi-Fi 2.4 GHz built in — no hub or gateway required
- ENGO Smart app control (iOS & Android, Tuya Cloud)
- Programmable timer — adjustable operating hours
- Built-in thermostat with adjustable hysteresis (±1°C to ±20°C)
- Display accuracy: 0.5°C
- Relay output: NO/COM/NC, rated 5(2)A at 230V
- S1/COM input: NTC temperature sensor or volt-free contact
- 230V AC 50Hz power supply
- Intuitive control panel and clear display
- White finish (see EHW-B for black)
- Compact 90 × 90 × 44 mm housing
- Wall mount installation
Technical Specifications
| Specification | Value |
|---|---|
| Model | EHW-W |
| Colour | White |
| Power Supply | 230V AC / 50Hz |
| Communication | Wi-Fi 2.4 GHz (no hub required) |
| App | ENGO Smart (Tuya Cloud) — iOS & Android |
| Relay Output | NO/COM/NC, 5(2)A at 230V AC |
| Sensor/Input (S1/COM) | NTC temperature sensor or volt-free contact |
| Control Algorithm | Hysteresis (±1°C to ±20°C) |
| Display Accuracy | 0.5°C |
| Dimensions | 90 × 90 × 44 mm |
| Mounting | Wall mount |
Installation Notes
Installation must be carried out by a qualified person per BS 7671. Ensure the relay output rating is appropriate for the connected load.
- Connect 230V L and N to the power supply terminals
- Wire NO/COM output to the heater supply (use external contactor for loads over 5A)
- Connect NTC sensor to S1/COM for thermostat function
- Wi-Fi: 2.4 GHz only — ensure your phone is on the 2.4 GHz band during initial app setup
- Schedule and setpoints can be configured on the device display or via the ENGO Smart app
Frequently Asked Questions
Can this control a standard immersion heater?
Yes, but most immersion heaters draw ~13A which exceeds the relay's 5A rating. Wire the EHW's output to a 16A contactor coil, and let the contactor switch the immersion heater. The EHW controls the contactor; the contactor controls the heater.
Is a separate thermostat needed?
No — the EHW-W has a built-in thermostat. However, it requires an external NTC temperature sensor connected to S1/COM to use the thermostat function. Without the sensor, only timed on/off control is available.
Do I need the ENGO Smart app?
No — the EHW-W can be programmed fully using the onboard display and buttons. The app provides the added convenience of remote access and monitoring.
Is there a black version?
Yes — the EHW-B is identical in specification but finished in matt black. See the EHW-B listing.
Does it work with smart tariffs like Octopus Go?
Yes — programme the timer schedule to match your cheap-rate electricity window and the EHW-W will automatically run the heater only during those hours.
What's in the Box
- 1× EHW-W WiFi hot water timer (white)
- Wall mounting fixings
- Quick installation guide
Note: NTC temperature sensor sold separately. For the black version see EHW-B.
Installation by qualified person per BS 7671. Relay rated 5(2)A — use external contactor for loads exceeding 5A. 2.4 GHz Wi-Fi only. Black version available: EHW-B.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
The ENGO EHW-W is a WiFi-enabled programmable hot water timer and thermostat in a clean white finish — designed to put your domestic water heater on a smart schedule. Control it remotely via the ENGO Smart app, programme it to run only during off-peak electricity hours, and rely on the built-in thermostat to maintain your preferred water temperature. Compatible with most electric water heaters and immersion cylinders. No hub needed.
Why Choose the ENGO EHW-W?
Full remote control, scheduling, and monitoring from anywhere via iOS or Android — no hub needed.
Set exactly when the heater runs — avoids wasted energy heating water at times it's not needed.
Monitors and maintains water temperature via an external NTC sensor — no separate thermostat device needed.
2.4 GHz Wi-Fi built into the unit — connects directly to your home network without a gateway.
Programme to run exclusively on Economy 7, Octopus Go, or other cheap-rate overnight electricity tariffs.
S1/COM terminal accepts an NTC temperature sensor or volt-free contact for versatile control options.
Clean white finish matches standard UK switches and sockets — blends seamlessly into any room. Black version (EHW-B) also available.
Programme and operate directly from the display and buttons — no app required for day-to-day use.
Suitable For
About the EHW-W
The EHW-W is the white version of the EHW series — identical in specification and function to the EHW-B, differing only in finish. It mounts on the wall near the water heater and switches the heater's mains supply through its built-in relay according to the set schedule and thermostat temperature.
On Economy 7, Octopus Go, or similar time-of-use tariffs, hot water can cost significantly more to heat during peak daytime hours than overnight. The EHW-W makes it simple to programme the heater to run only during cheap-rate periods — once set up in the app, it runs automatically every day without any manual adjustment.
The built-in thermostat uses an external NTC temperature sensor (connected to S1/COM) to monitor the water or cylinder temperature and switch the heater according to the hysteresis setpoint. The hysteresis band is adjustable between ±1°C and ±20°C — tighter bands maintain temperature more precisely; wider bands allow greater fluctuation for less frequent switching.
The built-in relay is rated 5(2)A. For most standard immersion heaters (3 kW / ~13A), wire the EHW's output to a suitable 16A contactor, with the EHW controlling the contactor coil. The EHW controls the contactor; the contactor switches the heater.
Key Features
- Wi-Fi 2.4 GHz built in — no hub or gateway required
- ENGO Smart app control (iOS & Android, Tuya Cloud)
- Programmable timer — adjustable operating hours
- Built-in thermostat with adjustable hysteresis (±1°C to ±20°C)
- Display accuracy: 0.5°C
- Relay output: NO/COM/NC, rated 5(2)A at 230V
- S1/COM input: NTC temperature sensor or volt-free contact
- 230V AC 50Hz power supply
- Intuitive control panel and clear display
- White finish (see EHW-B for black)
- Compact 90 × 90 × 44 mm housing
- Wall mount installation
Technical Specifications
| Specification | Value |
|---|---|
| Model | EHW-W |
| Colour | White |
| Power Supply | 230V AC / 50Hz |
| Communication | Wi-Fi 2.4 GHz (no hub required) |
| App | ENGO Smart (Tuya Cloud) — iOS & Android |
| Relay Output | NO/COM/NC, 5(2)A at 230V AC |
| Sensor/Input (S1/COM) | NTC temperature sensor or volt-free contact |
| Control Algorithm | Hysteresis (±1°C to ±20°C) |
| Display Accuracy | 0.5°C |
| Dimensions | 90 × 90 × 44 mm |
| Mounting | Wall mount |
Installation Notes
Installation must be carried out by a qualified person per BS 7671. Ensure the relay output rating is appropriate for the connected load.
- Connect 230V L and N to the power supply terminals
- Wire NO/COM output to the heater supply (use external contactor for loads over 5A)
- Connect NTC sensor to S1/COM for thermostat function
- Wi-Fi: 2.4 GHz only — ensure your phone is on the 2.4 GHz band during initial app setup
- Schedule and setpoints can be configured on the device display or via the ENGO Smart app
Frequently Asked Questions
Can this control a standard immersion heater?
Yes, but most immersion heaters draw ~13A which exceeds the relay's 5A rating. Wire the EHW's output to a 16A contactor coil, and let the contactor switch the immersion heater. The EHW controls the contactor; the contactor controls the heater.
Is a separate thermostat needed?
No — the EHW-W has a built-in thermostat. However, it requires an external NTC temperature sensor connected to S1/COM to use the thermostat function. Without the sensor, only timed on/off control is available.
Do I need the ENGO Smart app?
No — the EHW-W can be programmed fully using the onboard display and buttons. The app provides the added convenience of remote access and monitoring.
Is there a black version?
Yes — the EHW-B is identical in specification but finished in matt black. See the EHW-B listing.
Does it work with smart tariffs like Octopus Go?
Yes — programme the timer schedule to match your cheap-rate electricity window and the EHW-W will automatically run the heater only during those hours.
What's in the Box
- 1× EHW-W WiFi hot water timer (white)
- Wall mounting fixings
- Quick installation guide
Note: NTC temperature sensor sold separately. For the black version see EHW-B.
Installation by qualified person per BS 7671. Relay rated 5(2)A — use external contactor for loads exceeding 5A. 2.4 GHz Wi-Fi only. Black version available: EHW-B.
