The rooftop unit has a 10 percent limit

Comfort cooling, and the one exclusion to check

Comfort cooling means the appliances used for air conditioning in occupied buildings, and the definition names chillers, commercial split systems, dual-function heat pumps and packaged rooftop units (84.102). The section applies at a full charge of 15 pounds or more of an HFC or a substitute with a GWP above 53 (84.106(a)); a rooftop unit on R-410A of any size beyond the smallest clears both tests. The exclusion to check is the residential and light commercial air conditioning and heat pump subsector, which the section does not cover (84.106(a)(3)(ii)); a small split system serving one office may sit there, and a packaged unit serving a building floor usually does not. The applicability checker states the four criteria with their paragraphs.

The 10 percent limit and the annual inspection

The applicable leak rate for comfort cooling is 10 percent (84.106(c)(2)(iii)), half the commercial refrigeration figure. On a 60-pound rooftop unit, six pounds added in a year is the limit; the annualizing method scales an addition by the share of a year since the previous one (84.102), so three pounds added six months after the last top-up is 10 percent on the nose. Over it, the repair clock runs 30 days, with the initial and follow-up verification tests (84.106(d), (e)), and an appliance that has exceeded the rate is inspected for leaks once a year after a successful follow-up test until the calculations show a year under the limit (84.106(g)(1)(iii)).

What a building owner must keep

By 1 January 2026, or on installation, the full charge of every covered unit and how it was determined, kept until three years after the unit is retired (84.106(l)(1)). For every service visit, the record the contractor hands over (84.106(l)(4)) plus the full charge and the leak rate with the method (84.106(l)(2)). For every verification test, its date, method and result (84.106(l)(7)). All of it for at least three years (84.106(l)). A unit that loses 125 percent of its charge in a calendar year carries a report to the EPA by 1 March of the next year (84.106(j)); on a rooftop unit that is a lot of refrigerant, and on a leaking one it happens.

The building owner is usually the owner or operator in the rule's sense, whoever the tenant is, because the unit serves the building (84.102, owner or operator). Where a lease shifts maintenance to a tenant the record still has to exist somewhere both parties can reach; a ledger opened by link, with the contractor logging the visits, is that place.

What this page does not say

Whether your units are in compliance, or how your lease allocates the obligation. This page states the criteria and the arithmetic with their sections so you can read them yourself. The calculator does the arithmetic on your numbers and keeps it as a record; it certifies nothing.