New commercial refrigeration systems shall comply with the provisions of this section when installed in retail food stores 8,000 square feet or more conditioned area, and that utilize either refrigerated display cases, or walk-in coolers or freezers connected to remote compressor units or condensing units. The leak reduction measures apply to refrigeration systems containing high-global-warming potential (high-GWP) refrigerants with a GWP of 150 or greater. New refrigeration systems include both new facilities and the replacement of existing refrigeration systems in existing facilities.
Exception: Refrigeration systems containing low-global warming potential (low-GWP) refrigerant with a GWP value less than 150 are not subject to this section. Low-GWP refrigerants are nonozone-depleting refrigerants that include ammonia, carbon dioxide (CO2), and potentially other refrigerants.
Piping compliant with the California Mechanical Code
shall be installed to be accessible for leak protection and repairs. Piping runs using threaded pipe, copper tubing with an outside diameter (OD) less than 1
inch, flared tubing connections and short radius elbows
shall not be used in refrigerant systems except as noted below.
Threaded connections are permitted at the compressor rack.
Copper tubing with an OD less than 1/4 inch may be used in systems with a refrigerant charge of 5 pounds or less.
One-fourth-inch OD tubing shall be securely clamped to a rigid base to keep vibration levels below 8 mils.
Double-flared tubing connections may be used for pressure controls, valve pilot lines and oil.
Exception: Single-flared tubing connections may be used with a multiring seal coated with industrial sealant suitable for use with refrigerants and tightened in accordance with manufacturer's recommendations.
For vessels containing high-GWP refrigerant
, a rupture disc shall be installed between the outlet of the vessel and the inlet of the pressure relief valve.
A pressure gauge, pressure transducer or other device shall be installed in the space between the rupture disc and the relief valve inlet to indicate a disc rupture or discharge of the relief valve.
For systems with a refrigerant charge of 5 pounds or more, valve caps shall be brass or steel and not plastic.
If designed for it, the cap shall have a neoprene O-ring in place.
Chain tethers to fit over the stem are required for valves designed to have seal caps.
Exception: Valves with seal caps that are not removed from the valve during stem operation.
Refrigerated service cases holding food products containing vinegar and salt shall have evaporator coils of corrosion-resistant material, such as stainless steel; or be coated to prevent corrosion from these substances.
Consideration shall be given to the heat transfer efficiency of coil coating to maximize energy efficiency.
Refrigerant receivers with capacities greater than 200 pounds shall be fitted with a device that indicates the level of refrigerant in the receiver.
The system shall be pressure tested during installation prior to evacuation and charging.
The system shall be charged with regulated dry nitrogen and appropriate tracer gas to bring system pressure up to 300 psig
Check the system for leaks, repair any leaks, and retest for pressure using the same gauge.
The system shall stand, unaltered, for 24 hours with no more than a +/- one pound pressure change from 300 psig
, measured with the same gauge.
The system shall be evacuated after pressure testing and prior to charging.
Pull a system vacuum down to at least 1000 microns (+/- 50 microns), and hold for 30 minutes.
Pull a second system vacuum to a minimum of 500 microns and hold for 30 minutes.
Pull a third vacuum down to a minimum of 300 microns, and hold for 24 hours with a maximum drift of 100 microns over a 24-hour period.