International. Greenheck's direct air-to-gas make-up units now use R-454B, an Environmental Protection Agency-mandated A2L refrigerant with low GWP.
Because R-454B has a slight flammability potential, the units were third-party tested for all relevant product safety standards, including UL 60335-2-40. The tests certified that the refrigerant leak detection and mitigation systems are operating at full efficiency.
Providing 100% outdoor air, Greenheck's DGX units also feature Direct Expansion Cooling (PDX), which houses all cooling components in a compact rooftop unit. Its improved design also includes micro-channel coils, which have parallel flow tubes with small channels that carry coolant.
Compared to standard coils, microchannel coils are on average 40% smaller, use 50% less refrigerant, and transfer heat with 40% more efficiency.
