R-123 Chiller Annual Leak Rate and Repair Deadline
A 400-ton R-123 centrifugal chiller provides comfort cooling for a 12-story office building. The appliance nameplate charge is 550 lb. The maintenance log shows that over the last 12 months the facility added 78 lb of R-123 to keep the chiller running. The technician also notices oil residue at the evaporator flange and the purge unit has been cycling more often than usual. The building owner has not performed any leak repair verification tests. The technician is asked to determine whether the appliance is subject to the Section 608 leak repair requirements, what actions are required, and what records must be kept. The facility uses a certified refrigerant recovery machine and has a recovery cylinder available. The chiller is not an industrial process refrigeration appliance. The owner is concerned about cost and asks whether a retrofit plan is required.
1. Calculate the annual leak rate. Does it exceed the EPA threshold for comfort cooling? Show your work.
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Leak rate = (refrigerant added over 12 months ÷ full charge) × 100. Here, (78 lb ÷ 550 lb) × 100 = 14.18%. The EPA leak rate threshold for comfort cooling is 10% per year. Because 14.18% is greater than 10%, the appliance is subject to the leak repair requirements. Note also that 14.18% exceeds 125% of the 10% threshold (12.5%), which triggers additional planning requirements discussed in the next task.
2. What are the required repair and verification deadlines? Does the owner need to submit a retrofit or retirement plan?
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Because the leak rate exceeds 10%, the owner must repair the leak within 30 days of discovering the exceedance, unless an extension applies. After repair, the owner must perform an initial verification test within 30 days to confirm the repair was successful, and a follow-up verification test within 12 months. Because the leak rate of 14.18% also exceeds 125% of the threshold (12.5%), the owner must submit a retrofit or retirement plan to EPA within 30 days and complete the retrofit or retirement within 1 year. The plan must be kept on site. The technician should document the oil residue at the evaporator flange as the likely leak location and repair it before verification.
3. What records must the owner keep, and for how long?
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Under Section 608, the owner of an appliance with 50 lb or more of refrigerant must keep records of refrigerant purchased, added, recovered, and disposed of; leak inspections; repairs; initial and follow-up verification tests; and any retrofit or retirement plan. These records must be retained for at least 3 years. The technician should also record the date and amount of each refrigerant addition and the name of the certified technician performing the work.