Ammonia/CO2 Refrigeration System Evaluation at a Food Processing Facility
The HVAC&R world is undergoing significant changes, with regulatory bodies moving to reduce the use of refrigerants with high global warming potential (GWP). In commercial and industrial applications, ammonia refrigerant is a common solution which has zero GWP, but its applicability is limited because of mild flammability and toxicity concerns. In these applications R404A and R507A are common refrigerants today, but because of their high GWPs they face growing regulatory restrictions.
This report describes a field test of an alternative technology: a system using ammonia as the primary fluid and CO2 as a pumped volatile secondary fluid. This allows the ammonia charge to be much smaller than an equivalent all-ammonia system, while distributing only CO2 into the building. The system was installed in a food production facility in Irvine, California and is monitored along with existing, baseline conventional-refrigerant equipment, to study performance. The study documents the findings of differences in energy and power consumption as well as observations and learnings from the process of transitioning from a baseline system to a new, alternative-refrigerant approach.