Refrigeration and freezing are important processes in production, storaging and trading of food and beverages. The natural refrigerants (CO2, NH3, C3H8) choice for these sectors is gaining more and more traction. The main reasons for CO2 growing adoption are: international and local regulations, environmental responsibility of enterprises and CO2 refrigeration systems efficiency.
Carbon Dioxide (CO2, R744) is widely used in commercial and industrial refrigeration applications such as:
- supermarkets and grocery stores
- foodservice facilities
- cold rooms and walk-in freezers
- industrial cold storages
- food manufacturing and processing
CO2 is heavier than air, colorless and odorless, which means that it is impossible to control its level without special measurement equipment. R744 refrigerant concentration level must be controlled in accordance with local regulations. Usually, threshold limits, depending on a country, are: 5 000 ppm, 19 000 ppm or 40 000 ppm (Immediately Dangerous to Life or Health).
CO2 leak detection problems
The temperature in commercial and industrial refrigeration can drop down to -25℃ (in some places even down to -40℃). Most Carbon Dioxide sensors do not work in such conditions, as they are developed to operate at temperatures not lower than 0℃ (sometimes, not lower than -10℃). For this reason, many CO2 sensors are not suitable.
The second major problem is condensation. With the constant fridges and freezers opening and closing, the temperature inside them rises, as a result of which condensation forms. It gets on the sensor head and freezes after the temperature drops down again. Сonsequently, the CO2 detector stops operating or gives false readings.
Typical detection ranges for most Carbon Dioxide detectors are up to 2 000 ppm, 5 000 ppm or 10 000 ppm. It is also a problem since some of the customers need alarms to be set at 19 000 ppm and 40 000 ppm.
In summary, you can observe three important problems when detecting CO2 leakages in refrigeration applications: low temperatures, condensation and need for a higher detection range.
Evikon MCI has solutions
Evikon MCI uses specialized sensors from world’s leading manufacturers that can operate at very low temperatures. The built-in heating element prevents sensor frostbite and allows it to operate at temperatures down to -40℃.
Condensation prevention module solves the problem of condensation entering the sensor by constantly maintaining a certain temperature.
Choice of different sensors, both with a range of 0-10 000 ppm and a range of 0-50 000 ppm (up to 100% CO2 on request), helps to find the most ideal solution for a client in both commercial and industrial refrigeration.