Difluoromethane – known as R32 – seems to be winning the heart of manufacturers in the world of ventilation due to the advantages of the refrigerant:
• It has a low GWP (Global Warning Potential) that is 550-675;
• It has a low impact on the ozone layer (i.e. ecologically friendly);
• It optimises the performance of the thermodynamic circuit of an air conditioner.

Due to these advantages, the R32 has become one of the reference refrigerants in Japan where Japanese manufacturers have started using it. This is particularly the case of Daikin, which  has already taken the initiative to equip its devices to R32, at least regarding to small installations.

R32: an ignition hazard hint
The main problem of the R32 in its development is the suspicion that this gas is potentially flammable and therefore is a fire risk to facilities. Japanese manufacturers, universities and associations in this domain have already raised this issue.

The association of Japanese industries refrigeration and air conditioning (JRAIA) also addressed the issue. It has conducted studies on potential fire hazards associated with the use of R32 and R1234yf in VRF systems and their report shows that risks exist for restaurants and karaoke bars using vertical or wall air conditioners, where natural ventilation is almost nonexistent.

The future of R32 in ventilation

So why does Daikin use R32? Indeed Daikin units with R32 are already sent around the world, in Europe, especially in Australia. This is simply because there are not only bad things with R32. Although a risk of fire was discovered, that risk remains minimal. The specialists are talking about the average level of flammability is a safety class A2. According to the standard NIOSCH, R32 gas would only be a simple asphyxiant and therefore not explosive.

The JRAIA study also reveals that the risks are lower when there is natural ventilation in the room. One thing to know about R32, which will be notified in manuals to be published this autumn, is the handling and installation of equipment using R32.