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ENGO EFS300 Floor Temperature Sensor – NTC 10kΩ, 3m Cable, for Underfloor Heating Thermostats
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ENGO EFS300 Floor Temperature Sensor – NTC 10kΩ, 3m Cable, for Underfloor Heating Thermostats

ENGO EFS300 Floor Temperature Sensor – NTC 10kΩ, 3m Cable, for Underfloor Heating Thermostats

NTC 10kΩ 3 m Cable −10°C to 100°C 5-Year Warranty

The ENGO EFS300 is a passive NTC 10kΩ temperature sensor on a 3-metre cable, designed for installation in or on floors, pipes, cylinders, or any surface where an external temperature reading is needed. It is the standard companion sensor for the ENGO ONE thermostat range (EONE-230W/B, EONE-BATW/B), the EREL-16ZB smart relay, and several other ENGO products — enabling floor protection, "comfortable floor" mode, and temperature-triggered automation.

A dedicated floor sensor is essential in any underfloor heating system where you want to protect the floor surface from overheating — particularly important with laminate, engineered wood, or LVT flooring where temperatures above around 27–29°C can cause damage or voiding of the floor warranty. The EFS300 connects to the S1/COM terminals found on compatible ENGO thermostats and relays, adding a second temperature reading point that the controller can use for floor limiting, pipe monitoring, or automation rules.

Why Choose the ENGO EFS300?

🌡️ Floor Overheating ProtectionLimits the floor surface temperature to your set maximum — protecting laminate, wood, and LVT floors from heat damage while allowing the room to reach its target setpoint.
🛁 "Comfortable Floor" ModeWorks with ENGO ONE thermostats to keep the floor at a minimum warmth level regardless of the room air temperature — ideal for tiled bathrooms and wet rooms.
📏 3-Metre CableThe generous cable length makes routing to the thermostat or wiring centre straightforward without extensions — enough for most standard room layouts.
🔌 Plug-and-Play CompatibleDesigned to connect directly to the S1/COM sensor input on EONE series thermostats, EREL-16ZB smart relay, and other compatible ENGO products — no additional hardware needed.
🌐 Multi-Purpose SensingNot limited to floors — can monitor pipe temperature, cylinder temperature, ambient air in any location, or any device surface within cable reach.
🏭 Suitable for In-Floor InstallationThe sensor probe is designed for embedding in screed or under floor coverings — the cable exits cleanly to the wall chase or conduit.
⚡ Enables Smart AutomationWhen connected to the EREL-16ZB relay, the EFS300 temperature reading can trigger rules and automations in the ENGO Smart app — for example, frost protection for a hot water pipe or cylinder monitoring.
🛡️ 5-Year WarrantyBacked by ENGO's standard 5-year manufacturer's warranty.

Suitable For

ENGO EONE-230W / EONE-230B ENGO EONE-BATW / EONE-BATB ENGO EREL-16ZB Smart Relay ENGO EREL-16WIFI Smart Relay ENGO E10-W / E10-B Thermostats Underfloor Heating Systems Laminate & Wood Floor Protection Bathroom & Wet Room UFH Pipe Temperature Monitoring Hot Water Cylinder Monitoring Frost Protection Applications Smart Home Automation Rules

About the EFS300

The EFS300 is a passive NTC (Negative Temperature Coefficient) thermistor sensor with a nominal resistance of 10kΩ at 25°C. It requires no power supply of its own — the resistance value changes with temperature, and the connected thermostat or relay reads this change to calculate the temperature. This is the same sensor type used across the ENGO product range, ensuring reliable, accurate readings throughout the measurement range of −10°C to 100°C.

🛁 "Comfortable Floor" Mode — How It Works
When connected to an EONE series thermostat, the EFS300 enables "Comfortable Floor" mode: the thermostat monitors both the room air temperature (via its internal sensor) and the floor surface temperature (via the EFS300). You can set a minimum floor temperature — for example 22°C in a bathroom — so the floor stays pleasantly warm even when the room has already reached its air temperature setpoint. Simultaneously, you can set a maximum floor temperature (typically 27°C for wood, 29°C for tile) to prevent overheating and floor damage. This dual-limit control is the most intelligent way to manage UFH in rooms with sensitive floor coverings.

The 3 m cable with 2×0.5 mm² cross-section is thin enough to be embedded in floor screed or routed under skirting boards and into a wall chase. For new installations, the sensor probe should be positioned in the floor mid-way between two heating pipes, approximately 50–100 mm from the wall — this gives the most representative reading of average floor surface temperature rather than a hot-spot directly above a pipe. The cable end connects to the S1 and COM terminals on the thermostat, relay, or other compatible ENGO device.

✅ Compatible ENGO Products

EONE-230W, EONE-230B, EONE-BATW, EONE-BATB (via S1/COM sensor input) · EREL-16ZB and EREL-16WIFI smart relays (S1/S2 input) · E10-W, E10-B thermostats · EFAN series fan coil thermostats (S1/S2 pipe or floor sensor input). Always confirm compatibility in the product manual for your specific thermostat model.

Key Features

  • NTC 10kΩ thermistor — standard type compatible across the ENGO product range
  • Measuring range: −10°C to 100°C
  • 3-metre cable length — 2×0.5 mm² cross-section
  • Designed for in-floor installation — probe suitable for embedding in screed
  • Also suitable for pipe, cylinder, ambient air, or surface temperature measurement
  • Enables floor overheating protection in compatible thermostats
  • Enables "Comfortable Floor" mode in ENGO ONE thermostats
  • Enables temperature-triggered automation rules when connected to EREL-16ZB
  • Connects to S1/COM sensor terminals — no power supply required
  • 5-year manufacturer's warranty
  • EAN: 5905481996338

Technical Specifications

Specification Detail
Model EFS300
Sensor Type NTC thermistor
Nominal Resistance 10kΩ at 25°C
Measuring Range −10°C to 100°C
Cable Length 3 m
Cable Cross-Section 2×0.5 mm²
Connection S1/COM sensor terminals on compatible ENGO devices
Power Supply None — passive sensor
Compatible Products EONE-230W/B, EONE-BATW/B, EREL-16ZB, EREL-16WIFI, E10-W/B, EFAN series
Warranty 5 years
EAN 5905481996338

Installation Notes

For floor installation in new screed, lay the sensor probe in a conduit or protective sleeve mid-way between two UFH pipes, approximately 50–100 mm from the nearest wall. The sleeve allows the sensor to be replaced in future without disturbing the floor. Route the cable up the wall in a chase to the thermostat or wiring centre. Connect the two wires to the S1 and COM terminals — polarity does not matter for a passive NTC sensor. Once connected, configure the thermostat's sensor input to "Floor sensor" in the installer settings, and set your desired floor minimum and maximum temperature limits.

For pipe or cylinder monitoring, secure the probe to the pipe or vessel surface with tape or a clip and insulate over the top to prevent the ambient air temperature from affecting the reading. For frost protection applications, the sensor can be placed in any exposed location where you want to trigger heating if the temperature drops below a threshold.

Frequently Asked Questions

Which ENGO thermostats work with the EFS300?

The EFS300 is compatible with the EONE-230W, EONE-230B, EONE-BATW, EONE-BATB, E10-W, E10-B, and the EFAN fan coil thermostat range. It also connects to the S1/S2 input of the EREL-16ZB and EREL-16WIFI smart relays. Always check the wiring diagram for your specific thermostat model.

Do I need the EFS300 for my UFH system?

It is not mandatory, but it is strongly recommended for any installation with laminate, engineered wood, or LVT flooring. It enables floor temperature limiting, which protects the floor covering from heat damage. It is also needed if you want to use the "Comfortable Floor" mode in ENGO ONE thermostats.

Can I use the EFS300 to measure air temperature instead of floor temperature?

Yes — the EFS300 can measure the temperature of any surface, medium, or ambient air within the cable's reach. However, for measuring room air temperature, the thermostat's internal sensor is typically more accurate (positioned away from walls and draughts). The EFS300 is better suited to floor, pipe, cylinder, or surface applications.

Is the 3 m cable long enough?

For most room layouts where the thermostat is positioned on an adjacent wall, 3 m is sufficient. If you need a longer run, the cable can be extended using standard 2-core cable of the same or larger cross-section — NTC sensor cables are not sensitive to moderate cable lengths, though very long runs (over 10–15 m) may introduce slight reading inaccuracy. Use screened cable if running near mains wiring.

Does the EFS300 need a power supply?

No — it is a completely passive sensor. The connected thermostat or relay provides a small reference voltage and reads the resistance of the thermistor to calculate temperature. Simply connect the two sensor wires to the S1 and COM terminals.

What's in the Box

  • 1× ENGO EFS300 NTC 10kΩ temperature sensor with 3 m cable
  • Quick installation guide
⚠️ Please Note: The EFS300 must be used with a compatible ENGO thermostat or relay that has an NTC sensor input (S1/COM terminals). It is not a standalone device and will not function without a compatible host product. For floor installation, a protective conduit sleeve is recommended to allow future replacement of the sensor without disturbing the floor covering. Always follow the floor manufacturer's maximum temperature recommendations when setting floor temperature limits.
$5.20

Original: $14.85

-65%
ENGO EFS300 Floor Temperature Sensor – NTC 10kΩ, 3m Cable, for Underfloor Heating Thermostats

$14.85

$5.20

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ENGO EFS300 Floor Temperature Sensor – NTC 10kΩ, 3m Cable, for Underfloor Heating Thermostats - Image 2
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ENGO EFS300 Floor Temperature Sensor – NTC 10kΩ, 3m Cable, for Underfloor Heating Thermostats

NTC 10kΩ 3 m Cable −10°C to 100°C 5-Year Warranty

The ENGO EFS300 is a passive NTC 10kΩ temperature sensor on a 3-metre cable, designed for installation in or on floors, pipes, cylinders, or any surface where an external temperature reading is needed. It is the standard companion sensor for the ENGO ONE thermostat range (EONE-230W/B, EONE-BATW/B), the EREL-16ZB smart relay, and several other ENGO products — enabling floor protection, "comfortable floor" mode, and temperature-triggered automation.

A dedicated floor sensor is essential in any underfloor heating system where you want to protect the floor surface from overheating — particularly important with laminate, engineered wood, or LVT flooring where temperatures above around 27–29°C can cause damage or voiding of the floor warranty. The EFS300 connects to the S1/COM terminals found on compatible ENGO thermostats and relays, adding a second temperature reading point that the controller can use for floor limiting, pipe monitoring, or automation rules.

Why Choose the ENGO EFS300?

🌡️ Floor Overheating ProtectionLimits the floor surface temperature to your set maximum — protecting laminate, wood, and LVT floors from heat damage while allowing the room to reach its target setpoint.
🛁 "Comfortable Floor" ModeWorks with ENGO ONE thermostats to keep the floor at a minimum warmth level regardless of the room air temperature — ideal for tiled bathrooms and wet rooms.
📏 3-Metre CableThe generous cable length makes routing to the thermostat or wiring centre straightforward without extensions — enough for most standard room layouts.
🔌 Plug-and-Play CompatibleDesigned to connect directly to the S1/COM sensor input on EONE series thermostats, EREL-16ZB smart relay, and other compatible ENGO products — no additional hardware needed.
🌐 Multi-Purpose SensingNot limited to floors — can monitor pipe temperature, cylinder temperature, ambient air in any location, or any device surface within cable reach.
🏭 Suitable for In-Floor InstallationThe sensor probe is designed for embedding in screed or under floor coverings — the cable exits cleanly to the wall chase or conduit.
⚡ Enables Smart AutomationWhen connected to the EREL-16ZB relay, the EFS300 temperature reading can trigger rules and automations in the ENGO Smart app — for example, frost protection for a hot water pipe or cylinder monitoring.
🛡️ 5-Year WarrantyBacked by ENGO's standard 5-year manufacturer's warranty.

Suitable For

ENGO EONE-230W / EONE-230B ENGO EONE-BATW / EONE-BATB ENGO EREL-16ZB Smart Relay ENGO EREL-16WIFI Smart Relay ENGO E10-W / E10-B Thermostats Underfloor Heating Systems Laminate & Wood Floor Protection Bathroom & Wet Room UFH Pipe Temperature Monitoring Hot Water Cylinder Monitoring Frost Protection Applications Smart Home Automation Rules

About the EFS300

The EFS300 is a passive NTC (Negative Temperature Coefficient) thermistor sensor with a nominal resistance of 10kΩ at 25°C. It requires no power supply of its own — the resistance value changes with temperature, and the connected thermostat or relay reads this change to calculate the temperature. This is the same sensor type used across the ENGO product range, ensuring reliable, accurate readings throughout the measurement range of −10°C to 100°C.

🛁 "Comfortable Floor" Mode — How It Works
When connected to an EONE series thermostat, the EFS300 enables "Comfortable Floor" mode: the thermostat monitors both the room air temperature (via its internal sensor) and the floor surface temperature (via the EFS300). You can set a minimum floor temperature — for example 22°C in a bathroom — so the floor stays pleasantly warm even when the room has already reached its air temperature setpoint. Simultaneously, you can set a maximum floor temperature (typically 27°C for wood, 29°C for tile) to prevent overheating and floor damage. This dual-limit control is the most intelligent way to manage UFH in rooms with sensitive floor coverings.

The 3 m cable with 2×0.5 mm² cross-section is thin enough to be embedded in floor screed or routed under skirting boards and into a wall chase. For new installations, the sensor probe should be positioned in the floor mid-way between two heating pipes, approximately 50–100 mm from the wall — this gives the most representative reading of average floor surface temperature rather than a hot-spot directly above a pipe. The cable end connects to the S1 and COM terminals on the thermostat, relay, or other compatible ENGO device.

✅ Compatible ENGO Products

EONE-230W, EONE-230B, EONE-BATW, EONE-BATB (via S1/COM sensor input) · EREL-16ZB and EREL-16WIFI smart relays (S1/S2 input) · E10-W, E10-B thermostats · EFAN series fan coil thermostats (S1/S2 pipe or floor sensor input). Always confirm compatibility in the product manual for your specific thermostat model.

Key Features

  • NTC 10kΩ thermistor — standard type compatible across the ENGO product range
  • Measuring range: −10°C to 100°C
  • 3-metre cable length — 2×0.5 mm² cross-section
  • Designed for in-floor installation — probe suitable for embedding in screed
  • Also suitable for pipe, cylinder, ambient air, or surface temperature measurement
  • Enables floor overheating protection in compatible thermostats
  • Enables "Comfortable Floor" mode in ENGO ONE thermostats
  • Enables temperature-triggered automation rules when connected to EREL-16ZB
  • Connects to S1/COM sensor terminals — no power supply required
  • 5-year manufacturer's warranty
  • EAN: 5905481996338

Technical Specifications

Specification Detail
Model EFS300
Sensor Type NTC thermistor
Nominal Resistance 10kΩ at 25°C
Measuring Range −10°C to 100°C
Cable Length 3 m
Cable Cross-Section 2×0.5 mm²
Connection S1/COM sensor terminals on compatible ENGO devices
Power Supply None — passive sensor
Compatible Products EONE-230W/B, EONE-BATW/B, EREL-16ZB, EREL-16WIFI, E10-W/B, EFAN series
Warranty 5 years
EAN 5905481996338

Installation Notes

For floor installation in new screed, lay the sensor probe in a conduit or protective sleeve mid-way between two UFH pipes, approximately 50–100 mm from the nearest wall. The sleeve allows the sensor to be replaced in future without disturbing the floor. Route the cable up the wall in a chase to the thermostat or wiring centre. Connect the two wires to the S1 and COM terminals — polarity does not matter for a passive NTC sensor. Once connected, configure the thermostat's sensor input to "Floor sensor" in the installer settings, and set your desired floor minimum and maximum temperature limits.

For pipe or cylinder monitoring, secure the probe to the pipe or vessel surface with tape or a clip and insulate over the top to prevent the ambient air temperature from affecting the reading. For frost protection applications, the sensor can be placed in any exposed location where you want to trigger heating if the temperature drops below a threshold.

Frequently Asked Questions

Which ENGO thermostats work with the EFS300?

The EFS300 is compatible with the EONE-230W, EONE-230B, EONE-BATW, EONE-BATB, E10-W, E10-B, and the EFAN fan coil thermostat range. It also connects to the S1/S2 input of the EREL-16ZB and EREL-16WIFI smart relays. Always check the wiring diagram for your specific thermostat model.

Do I need the EFS300 for my UFH system?

It is not mandatory, but it is strongly recommended for any installation with laminate, engineered wood, or LVT flooring. It enables floor temperature limiting, which protects the floor covering from heat damage. It is also needed if you want to use the "Comfortable Floor" mode in ENGO ONE thermostats.

Can I use the EFS300 to measure air temperature instead of floor temperature?

Yes — the EFS300 can measure the temperature of any surface, medium, or ambient air within the cable's reach. However, for measuring room air temperature, the thermostat's internal sensor is typically more accurate (positioned away from walls and draughts). The EFS300 is better suited to floor, pipe, cylinder, or surface applications.

Is the 3 m cable long enough?

For most room layouts where the thermostat is positioned on an adjacent wall, 3 m is sufficient. If you need a longer run, the cable can be extended using standard 2-core cable of the same or larger cross-section — NTC sensor cables are not sensitive to moderate cable lengths, though very long runs (over 10–15 m) may introduce slight reading inaccuracy. Use screened cable if running near mains wiring.

Does the EFS300 need a power supply?

No — it is a completely passive sensor. The connected thermostat or relay provides a small reference voltage and reads the resistance of the thermistor to calculate temperature. Simply connect the two sensor wires to the S1 and COM terminals.

What's in the Box

  • 1× ENGO EFS300 NTC 10kΩ temperature sensor with 3 m cable
  • Quick installation guide
⚠️ Please Note: The EFS300 must be used with a compatible ENGO thermostat or relay that has an NTC sensor input (S1/COM terminals). It is not a standalone device and will not function without a compatible host product. For floor installation, a protective conduit sleeve is recommended to allow future replacement of the sensor without disturbing the floor covering. Always follow the floor manufacturer's maximum temperature recommendations when setting floor temperature limits.

Product Information

Shipping & Returns

Description

NTC 10kΩ 3 m Cable −10°C to 100°C 5-Year Warranty

The ENGO EFS300 is a passive NTC 10kΩ temperature sensor on a 3-metre cable, designed for installation in or on floors, pipes, cylinders, or any surface where an external temperature reading is needed. It is the standard companion sensor for the ENGO ONE thermostat range (EONE-230W/B, EONE-BATW/B), the EREL-16ZB smart relay, and several other ENGO products — enabling floor protection, "comfortable floor" mode, and temperature-triggered automation.

A dedicated floor sensor is essential in any underfloor heating system where you want to protect the floor surface from overheating — particularly important with laminate, engineered wood, or LVT flooring where temperatures above around 27–29°C can cause damage or voiding of the floor warranty. The EFS300 connects to the S1/COM terminals found on compatible ENGO thermostats and relays, adding a second temperature reading point that the controller can use for floor limiting, pipe monitoring, or automation rules.

Why Choose the ENGO EFS300?

🌡️ Floor Overheating ProtectionLimits the floor surface temperature to your set maximum — protecting laminate, wood, and LVT floors from heat damage while allowing the room to reach its target setpoint.
🛁 "Comfortable Floor" ModeWorks with ENGO ONE thermostats to keep the floor at a minimum warmth level regardless of the room air temperature — ideal for tiled bathrooms and wet rooms.
📏 3-Metre CableThe generous cable length makes routing to the thermostat or wiring centre straightforward without extensions — enough for most standard room layouts.
🔌 Plug-and-Play CompatibleDesigned to connect directly to the S1/COM sensor input on EONE series thermostats, EREL-16ZB smart relay, and other compatible ENGO products — no additional hardware needed.
🌐 Multi-Purpose SensingNot limited to floors — can monitor pipe temperature, cylinder temperature, ambient air in any location, or any device surface within cable reach.
🏭 Suitable for In-Floor InstallationThe sensor probe is designed for embedding in screed or under floor coverings — the cable exits cleanly to the wall chase or conduit.
⚡ Enables Smart AutomationWhen connected to the EREL-16ZB relay, the EFS300 temperature reading can trigger rules and automations in the ENGO Smart app — for example, frost protection for a hot water pipe or cylinder monitoring.
🛡️ 5-Year WarrantyBacked by ENGO's standard 5-year manufacturer's warranty.

Suitable For

ENGO EONE-230W / EONE-230B ENGO EONE-BATW / EONE-BATB ENGO EREL-16ZB Smart Relay ENGO EREL-16WIFI Smart Relay ENGO E10-W / E10-B Thermostats Underfloor Heating Systems Laminate & Wood Floor Protection Bathroom & Wet Room UFH Pipe Temperature Monitoring Hot Water Cylinder Monitoring Frost Protection Applications Smart Home Automation Rules

About the EFS300

The EFS300 is a passive NTC (Negative Temperature Coefficient) thermistor sensor with a nominal resistance of 10kΩ at 25°C. It requires no power supply of its own — the resistance value changes with temperature, and the connected thermostat or relay reads this change to calculate the temperature. This is the same sensor type used across the ENGO product range, ensuring reliable, accurate readings throughout the measurement range of −10°C to 100°C.

🛁 "Comfortable Floor" Mode — How It Works
When connected to an EONE series thermostat, the EFS300 enables "Comfortable Floor" mode: the thermostat monitors both the room air temperature (via its internal sensor) and the floor surface temperature (via the EFS300). You can set a minimum floor temperature — for example 22°C in a bathroom — so the floor stays pleasantly warm even when the room has already reached its air temperature setpoint. Simultaneously, you can set a maximum floor temperature (typically 27°C for wood, 29°C for tile) to prevent overheating and floor damage. This dual-limit control is the most intelligent way to manage UFH in rooms with sensitive floor coverings.

The 3 m cable with 2×0.5 mm² cross-section is thin enough to be embedded in floor screed or routed under skirting boards and into a wall chase. For new installations, the sensor probe should be positioned in the floor mid-way between two heating pipes, approximately 50–100 mm from the wall — this gives the most representative reading of average floor surface temperature rather than a hot-spot directly above a pipe. The cable end connects to the S1 and COM terminals on the thermostat, relay, or other compatible ENGO device.

✅ Compatible ENGO Products

EONE-230W, EONE-230B, EONE-BATW, EONE-BATB (via S1/COM sensor input) · EREL-16ZB and EREL-16WIFI smart relays (S1/S2 input) · E10-W, E10-B thermostats · EFAN series fan coil thermostats (S1/S2 pipe or floor sensor input). Always confirm compatibility in the product manual for your specific thermostat model.

Key Features

  • NTC 10kΩ thermistor — standard type compatible across the ENGO product range
  • Measuring range: −10°C to 100°C
  • 3-metre cable length — 2×0.5 mm² cross-section
  • Designed for in-floor installation — probe suitable for embedding in screed
  • Also suitable for pipe, cylinder, ambient air, or surface temperature measurement
  • Enables floor overheating protection in compatible thermostats
  • Enables "Comfortable Floor" mode in ENGO ONE thermostats
  • Enables temperature-triggered automation rules when connected to EREL-16ZB
  • Connects to S1/COM sensor terminals — no power supply required
  • 5-year manufacturer's warranty
  • EAN: 5905481996338

Technical Specifications

Specification Detail
Model EFS300
Sensor Type NTC thermistor
Nominal Resistance 10kΩ at 25°C
Measuring Range −10°C to 100°C
Cable Length 3 m
Cable Cross-Section 2×0.5 mm²
Connection S1/COM sensor terminals on compatible ENGO devices
Power Supply None — passive sensor
Compatible Products EONE-230W/B, EONE-BATW/B, EREL-16ZB, EREL-16WIFI, E10-W/B, EFAN series
Warranty 5 years
EAN 5905481996338

Installation Notes

For floor installation in new screed, lay the sensor probe in a conduit or protective sleeve mid-way between two UFH pipes, approximately 50–100 mm from the nearest wall. The sleeve allows the sensor to be replaced in future without disturbing the floor. Route the cable up the wall in a chase to the thermostat or wiring centre. Connect the two wires to the S1 and COM terminals — polarity does not matter for a passive NTC sensor. Once connected, configure the thermostat's sensor input to "Floor sensor" in the installer settings, and set your desired floor minimum and maximum temperature limits.

For pipe or cylinder monitoring, secure the probe to the pipe or vessel surface with tape or a clip and insulate over the top to prevent the ambient air temperature from affecting the reading. For frost protection applications, the sensor can be placed in any exposed location where you want to trigger heating if the temperature drops below a threshold.

Frequently Asked Questions

Which ENGO thermostats work with the EFS300?

The EFS300 is compatible with the EONE-230W, EONE-230B, EONE-BATW, EONE-BATB, E10-W, E10-B, and the EFAN fan coil thermostat range. It also connects to the S1/S2 input of the EREL-16ZB and EREL-16WIFI smart relays. Always check the wiring diagram for your specific thermostat model.

Do I need the EFS300 for my UFH system?

It is not mandatory, but it is strongly recommended for any installation with laminate, engineered wood, or LVT flooring. It enables floor temperature limiting, which protects the floor covering from heat damage. It is also needed if you want to use the "Comfortable Floor" mode in ENGO ONE thermostats.

Can I use the EFS300 to measure air temperature instead of floor temperature?

Yes — the EFS300 can measure the temperature of any surface, medium, or ambient air within the cable's reach. However, for measuring room air temperature, the thermostat's internal sensor is typically more accurate (positioned away from walls and draughts). The EFS300 is better suited to floor, pipe, cylinder, or surface applications.

Is the 3 m cable long enough?

For most room layouts where the thermostat is positioned on an adjacent wall, 3 m is sufficient. If you need a longer run, the cable can be extended using standard 2-core cable of the same or larger cross-section — NTC sensor cables are not sensitive to moderate cable lengths, though very long runs (over 10–15 m) may introduce slight reading inaccuracy. Use screened cable if running near mains wiring.

Does the EFS300 need a power supply?

No — it is a completely passive sensor. The connected thermostat or relay provides a small reference voltage and reads the resistance of the thermistor to calculate temperature. Simply connect the two sensor wires to the S1 and COM terminals.

What's in the Box

  • 1× ENGO EFS300 NTC 10kΩ temperature sensor with 3 m cable
  • Quick installation guide
⚠️ Please Note: The EFS300 must be used with a compatible ENGO thermostat or relay that has an NTC sensor input (S1/COM terminals). It is not a standalone device and will not function without a compatible host product. For floor installation, a protective conduit sleeve is recommended to allow future replacement of the sensor without disturbing the floor covering. Always follow the floor manufacturer's maximum temperature recommendations when setting floor temperature limits.