Abstract: A dual refrigerant refrigerating system provides a refrigeration cycle in which a primary refrigerant cools a secondary refrigerant in a primary evaporator into a partially frozen state, in which a fusion portion thereof is frozen. The primary refrigerant thus absorbs a secondary latent heat from secondary refrigerant, including a latent heat of fusion required for freezing the fusion portion. Secondary refrigerant is subsequently at least partially thawed, in a secondary evaporator, by re-absorption thereby of secondary latent heat from material proximal to secondary evaporator. Evaporation in secondary evaporator requires at least partial thawing of fusion portion, and thus latent heat of fusion is at least partially re-absorbed by secondary refrigerant, thus increasing secondary heat absorbed from material and facilitating refrigeration thereof. The system also provides defrost and heat reclaim capabilities.