Owners of commercial refrigeration systems containing 50
pounds of CFC or HCFC refrigerants are required by the Environmental Protection
Agency (EPA) to repair refrigerant leaks when the leak rate equals or exceeds
35 percent of the total system charge over a one-year period. It is the leak
rate and not the total amount of refrigerant lost that the EPA uses to
determine when a leak must be repaired.
For example, if a system containing 100 pounds of
refrigerant loses 5 pounds of refrigerant over a month’s period, it would
exceed the 35 percent trigger rate. Although a 5-pound loss is only 5 percent
of the total system charge, if left unrepaired, it would lose 60 pounds over a
year, which is 60 percent of the total system charge.
In order to comply with this regulation, equipment owners
must keep accurate service records documenting the date and type of service as
well as the quantity of refrigerant added to these systems. These records
should be maintained on site for a minimum of three years. There are several
refrigerant log booklets and software programs available to aid an owner in
these record-keeping requirements.
In order to determine the leak rate of a system, the full
refrigerant charge of the system must first be determined. This full charge
value will be used as the baseline when determining the leak rate of a system.
There are several ways an owner can determine the full refrigerant charge of a
system.
If available, they can rely on the documentation provided by
the equipment manufacturer. They could record the amount of refrigerant added
to a system after all the refrigerant has been recovered, the system evacuated,
and then recharged. They can calculate the full charge based on the component
sizes, refrigerant density, volume of piping, and other considerations. They
could use other baseline data available as long as they document how they
determine the full charge of the system.

FORMULA 1. (Click on the image for an enlarged view.)
Once the full refrigerant charge of a system has been
determined, Formula 1 can be used to calculate the leak rate of a system. For
example, if a commercial refrigeration system with a full refrigerant charge of
135 pounds has lost 15 pounds of refrigerant over the last 90 days, the leak
rate per year for this system would be 45 percent. (See Formula 2.)
This exceeds the EPA’s 35 percent trigger rate, and the
refrigerant leak would need to be located and repaired - which the owner has 30
days to do. This requirement can be waived if, within 30 days of discovery, the
owner develops a one-year retrofit or retirement plan for the leaking system.

FORMULA 2. (Click on the image for an enlarged view.)
Some equipment owners may not be aware of these EPA
regulations. Refrigeration contractors and their technicians need to inform
their customers of this regulation when servicing and maintaining these
systems. Refrigeration contractors should also be of assistance to their customers
both in the record-keeping requirements and when a leak rate has been exceeded.
This can be a great opportunity for refrigeration contractors, allowing them to
build a solid relationship with their customers and grow their customer base.
For more information on complying with the EPA’s regulation
on refrigerant leaks as well as other refrigerant regulations, go to www.epa.gov.
Publication
date: 06/04/2007