Seresco CWT Series Installation, Operation And Maintenance Manual page 23

A2L Refrigerant Mitigation Control
Dehumidifiers, that contain A2L (mildly flammable) refrigerant (like R454B), employ additional mechanisms
(devices and control algorithm) to ensure the safety in event of refrigerant leak.
Initial Ventilation Design and Emergency Venting
Danger of explosion of A2L refrigerant would occur if its concentration in the air would be above certain level. To
ensure that said concentration is never reached, safety consideration is embedded at the design and selection of
the dehumidifier for respective premise:
 Dehumidifier's min blower(s) capacity is selected in such a way that they will create enough of the airflow
to vent all the air (with leaked in refrigerant) into conditioned space at concentration much lower than
the dangerous one.
 The dehumidifier refrigerant charge and size (area, volume etc.) of conditioned space are matched in such
a way that conditioned space would allow for dilution of leaked refrigerant to the point (concentration)
that does not present danger.
December 2024
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Pic. E.2
OMM