Gas Alarm GX-D2

The CO₂ detector with external sensor: measure exactly where people breathe

The Schabus CO₂ Detector GX-D2 is a plug-and-play warning device for monitoring indoor air in rooms with many people, for example classrooms, offices, meeting rooms, waiting rooms and medical practices. Unlike the GX-D1, the NDIR infrared sensor is not located in the housing but in an external sensor unit with a 2.5 m cable. This allows you to choose the measuring point independently of the socket and place the sensor where people actually spend time. The detector reminds you to ventilate already at a concentration well below a hazardous level: with a clearly audible piezo alarm tone (approx. 90 dB) and a flashing red LED.

Exhaled air causes the concentration of carbon dioxide (CO₂) in the room to rise. From around 1,400 ppm the air quality is considered significantly impaired, and with persistently high values concentration and performance decline, the risk of infection increases as the immune system is also weakened. The GX-D2 is therefore deliberately set to be very sensitive: the pre-alarm occurs at approx. 2,000 ppm, the alarm at 2,500 ppm. This corresponds to roughly half the MAK value (TRGS 900), but is still not a life-threatening level. In contrast to CO₂ traffic lights with hygienic guideline values between 1,000 and 2,000 ppm, the GX-D2 only triggers an alarm at a higher concentration level, not already at slight comfort impairments.

The GX-D2 is simply plugged into a 230 V socket; batteries are not required. After about 3 minutes of warm-up time it is ready for operation. Nothing needs to be drilled on the device itself; you only place the sensor. The device has no options or variants.

Plug in, place the sensor, ventilate

The GX-D2 reliably reminds you to ventilate, without continuous beeping and without any operating effort.

The best measurement takes place where the people are

With the GX-D2 it is not the socket but you who determine the measuring point. This is particularly helpful in these cases:

• Larger rooms where the socket is far from the seating areas
• Angled floor plans
• Rooms with different occupancy zones
• Classrooms where the sensor should be at the breathing height of the pupils

What’s in the box

• Warning device GX-D2 (socket device) with external CO₂ sensor
• Operating instructions

How the GX-D2 is constructed

The GX-D2 consists of two parts: the socket device with evaluation and signal transmitters, and the external sensor, which is connected to the device via a permanently attached cable.

Position correctly and put into operation

Read the operating instructions thoroughly before installation and first commissioning. The device may only be installed in dry indoor rooms.

The right position

These locations are not suitable

• Places that could prevent the alarm from triggering, e.g. behind curtains or in cupboards
• Directly above a cooker or combustion appliance or above a sink
• Next to doors, windows, ventilation, fan or air conditioning
• Areas where dust, moisture or dirt can put the sensor out of operation

Commissioning step by step

1. Ensure a well-ventilated room before commissioning.
2. Position the sensor at the desired location and plug the GX-D2 into a 230 V socket. The three LEDs light up briefly one after the other and a short alarm sounds.
3. Wait for the sensor warm-up time of a few minutes (approx. 3). The green LED flashes. Move away from the device during this time and do not breathe on it.
4. When the green LED lights continuously, the GX-D2 is ready for operation.

The service life and reliability of the sensor increase significantly when the GX-D2 is operated in a regularly well-ventilated room. Around 30 minutes of fresh air per day is a desirable optimum.

How the GX-D2 reacts and how to check it

Behaviour in the event of an alarm

1. Open windows and doors and thoroughly ventilate the room or the house. Inform other people in the room.
2. Cross-ventilation is better and more effective than shock ventilation. Provide a few minutes of through-draught to ensure a good indoor climate for working and learning.
3. If necessary, mute the alarm tone with the test button.

Test with the test button

Press the test button for a few seconds. You hear the alarm tone and all three LEDs light up briefly. Only the LEDs and the acoustic alarm are tested; this test says nothing about the condition of the sensor.

Function test with exhaled air, recommended monthly

A person exhales approx. 4 to 5 % CO₂. Take a deep breath and slowly blow it onto the sensor. The sensor needs up to one minute reaction time; if necessary, repeat until the alarm. The manufacturer recommends the test monthly for your own safety. Clean the sensor regularly by removing dust by blowing, and keep moisture away from the sensor.

Sensor error and false alarm

Cleaning and maintenance

Avoid the influence of moisture (splash or rain water), dust and direct sunlight on the device. Clean it only with a dry linen cloth, which may be slightly dampened in case of heavy soiling. Do not use solvent-based cleaning agents.

Optional accessories

Manufacturer’s notes

• Read the operating instructions carefully before installation and commissioning and keep them
• Do not open the device; it contains no parts that can be serviced by the user
• Packaging material is not a toy and must be kept away from children
• Suitable for normal household use; not approved for other uses
• Intended for residential buildings, sales areas and rooms of small businesses such as workshops and service centres, each connected to the public low-voltage network
• Do not use in potentially explosive atmospheres or in industrial/commercial environments
• The declaration of conformity is available for download on the manufacturer’s website

Warranty, guarantee, return and disposal

The GX-D2 is covered by the statutory warranty of at least 2 years in the EU. The manufacturer Elektrotechnik Schabus additionally offers a 5-year guarantee that can be registered online. Repair and spare parts are available directly from the manufacturer, even beyond the statutory warranty. Personal specialist advice is available without a call centre directly from the manufacturer. In the event of a warranty claim, the device is sent in sufficiently packed with a description of the fault, proof of purchase as well as address and delivery address. The device must have been used in accordance with the operating instructions.

Return: In the event of a defect, first contact the manufacturer and state the complete address as well as the reason for return. Within Germany, a free returns label is sent by e-mail. Unpaid parcels will not be accepted, and unjustified returns that do not constitute a complaint will be charged subsequently.

The GX-D2 does not belong in household waste. The crossed-out wheeled bin symbol on the product reminds you to use the take-back systems for waste electrical and electronic equipment (WEEE No. DE91394868). Further information is available from your local waste advice centre or from the manufacturer.

Areas of application

• Classrooms, training and seminar rooms
• Day-care centres
• Offices and open-plan offices
• Meeting and conference rooms
• Waiting rooms and medical practices
• Recreation rooms
• Gastronomy and fitness studios
• Co-working spaces
• Workshops in small businesses
• Living rooms and household

The Schabus CO₂ Detector GX-D2: Because good air knows no compromises.

Frequently asked questions