April 13, 2017
ACCA, the Indoor Environment & Energy Efficiency Association, announces the release of ACCA Technical Bulletin 2017-1 (entitled Commercial Refrigeration Line Sizing). It is available through ACCA to its members at www.acca.org/techbulletins.
This Technical Bulletin discusses the advantages, disadvantages, procedures, and results of proper line sizing in commercial refrigeration systems (e.g. supermarkets, convenience stores, cold storage warehouses, etc.). This Technical Bulletin addresses line sizing for the following line types:
- Compressor discharge line;
- Liquid line;
- Suction line (and suction riser).
The refrigerants addressed are: R-22; R-134a; R-404A; R-407A; R-407C; R-448A; R-507C; and R-449A. Saturated suction temperatures range from -40ºF to +40ºF and the saturated condensing temperatures range from +50ºF to +135ºF; in increments of 10ºF. The “equivalent line lengths” of the refrigerant tubing is at: 50’, 100’, 150’, 200’, 250’, and 300’.
Large lines have more copper, and therefore, more weight and correspondingly higher cost per foot. Additionally, larger diameters are more difficult to braze and require longer assembly times. However, lines that are sized too small will result in increased pressure drops, which will raise energy usage, while providing negative impact on equipment life expectancy and performance.
Comments and questions can be submitted to Danny Halel, ACCA's manager of standards at danny.halel@acca.org.