LuxHeat Universal Heated Floor Sensor — 10K Ohm NTC (W04CGQ29)
The LuxHeat universal heated floor sensor is a replacement and backup temperature probe for electric radiant floor heating systems — providing your thermostat with a direct, accurate reading of actual floor surface temperature rather than room air temperature alone. Thermostats operating in floor sensing mode use this signal to prevent two common problems: overheating sensitive floor materials like hardwood, laminate, and engineered wood, and undershooting comfort on colder mornings when air temperature alone does not reflect how warm the floor actually is.
This radiant heat floor sensor is an NTC 10K Ohm probe calibrated at 77°F (25°C) — the standard specification accepted by virtually every major thermostat brand including OJ Microline (UDG-4999 and UDG4-4999), Aube, Honeywell, NuHeat, SunTouch, and Ditra Heat. The 15 ft (4.5 m) lead provides ample reach from the sensor body in the floor assembly back to the thermostat at the wall, covering most residential floor plans without an extension.
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NTC 10K Ohm at 77°F (25°C) — the universal standard radiant floor sensor specification; compatible with OJ Microline, Aube, Honeywell, NuHeat, SunTouch, Ditra, and most other brands that specify 10K Ohm NTC
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15 ft (4.5 m) lead — adequate reach for most residential installations from probe location under tile to thermostat at the wall
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Protects sensitive floor coverings — floor heating sensor mode on compatible thermostats enforces a maximum floor temperature limit, preventing damage to hardwood, laminate, and other heat-sensitive materials
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Recommended backup sensor — LuxHeat and most thermostat manufacturers recommend installing a second backup floor sensor for underfloor heating; this sensor is a compatible replacement for the probe included in LuxHeat cable kits
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Accurate NTC thermistor — reliable resistance-temperature response across the full operating range; radiant temperature sensor performance for both floor limit and floor-only thermostat modes
The LuxHeat floor temperature sensor (W04CGQ29) is sold individually and is compatible with the same NTC 10K Ohm specification included in the LuxHeat radiant floor heating cable kit. Free shipping within the contiguous US on all orders.
Frequently Asked Questions
Is this floor sensor compatible with my thermostat?
It is compatible if your thermostat manual lists "NTC 10K Ohm" or "10 kΩ at 25°C" as the floor sensor specification. This covers all current OJ Microline models (UDG-4999, UDG4-4999 and more), as well as Aube, Honeywell, NuHeat, SunTouch, and Ditra Heat — and the majority of residential radiant floor heating thermostats on the market. If your thermostat specifies a different resistance value (such as 12K, 15K, or 33K Ohm), this sensor will not be compatible.
Where should the floor sensor be placed during installation?
The sensor probe should be embedded in the floor assembly between two heating cable runs — not touching a cable directly, and not near the room perimeter where the floor stays cooler than the heated zone. A Pro Tip is to route the sensor inside a conduit that allows it to be pulled out and replaced without demolishing the floor, if needed. Your thermostat manual will include a diagram showing the recommended placement. During installation, this is one of the most important steps to get right — a poorly placed sensor can cause the system to run short or overshoot comfort.