How to install the temperature sensor in the heating mat?

To ensure that the sensor can be replaced in case of failure, the sensor must be installed in a flexible protective tube. Each nVent RAYCHEM heating set includes a protective tube for the floor temperature measurement sensor. Installation of the floor temperature sensor in the casing tube is a necessary step for any heating system and should not be skipped. Floor sensors can sometimes fail. Only the proper installation of the protective tube will allow the broken sensor to be replaced without problems.

Floor temperature sensor

A wired floor sensor should be included with the room thermostat, the most common type: NTC 10K at 25°C. NTC 10K sensors are very versatile, designed for temperature measurement in various fields of construction and industry. The measuring range, accuracy class and dimensions meet the standards used in automation. Thanks to mass production, we also meet them in sets with room thermostats.

What is the floor temperature sensor for?

Fixed-power heating cables and floor heating mats, according to the regulations, must be controlled by a thermostat that regulates the temperature using an external floor temperature sensor. Alternatively, the cables can be controlled by a thermostat that operates in room temperature sensing mode, but with a floor sensor temperature limiter. However, the thermostats themselves must ensure compliance with the Eco Design Directive.

The floor temperature sensor in combination with the thermostat:

• limits the floor temperature - the maximum should be 27°C,
• protects the user from the discomfort of a hot floor,
• protects the floor from damage - e.g. wooden floors, vinyl floors,
• protects heating cables from overheating.

How to check if the floor temperature sensor is good?

Installation of the floor temperature sensor

The floor temperature sensor is installed in the previously installed protective pipe. This tube must be placed directly in the heated floor exactly between the heating conductors of the heating mat or heating cable. This tubing is usually about 10 - 12 mm thick, which may require partially forcing it into the floor. The sensor must be placed, exactly in the middle between the two heating wires of the heating cable.

• The tip of the sensor must be placed at least 40 - 50 cm deep into the installation in the part of the floor on which nothing will stand.

• Install the temperature sensor tube evenly between the wires of the heating cable.
• Place the floor sensor as close to the top layer of the floor as possible.

Cover pipe for floor sensor

The pipe included in nVent RAYCHEM kits has a high strength and mechanical resistance of 750N. This protects against accidental stronger crushing.

Cap for the casing pipe

Before installing the casing pipe for the temperature sensor, it is necessary to protect it from the side that will be in the layer of glue or screed from getting "cement" water or mortar. In the heating kit, in addition to the casing pipe for the floor temperature sensor, manufacturers often add a cap. The cap should be brass so that it conducts heat better. It should be pressed into the protective tube included in the kit. Thus assembled components are mounted between the wires of the heating cable.

• Brass plug - example on the RAYCHEM T2Black heating set.

• Brass plug.

• Press the brass plug with the narrower end into the casing pipe.

• Press the brass plug with the narrower end into the casing pipe.

• Pressed brass cap into the installed pipe.

Easy replacement of the floor temperature sensor in the future

Floor sensors are system components that can fail. In order to be able to remove and reinstall it later, all arches should be made as smooth as possible. The example below shows the location of the arch between the wall and the floor. Note that the floor in this place (optionally it can be the wall) is more carved, which allows the installer to give the pipe the right shape.

• Correct installation of casing pipe with gentle curves in the corner of the wall - floor.

• Correct installation of casing pipe with gentle curves.

• Floor sensor exactly between heating pipes.

Typical installation error of the floor sensor

Never install the sensor on the bias! In this example, the temperature sensor probe may be just under the heating cable which will lead to an incorrect reading of the floor temperature.

• Wrongly installed floor temperature sensor pipe, do not install diagonally.

• In such a positioned pipe, the sensor probe may be too close to the heating cable, which will cause an incorrect temperature reading and rapid disconnection of the heating by the room thermostat.