The Q3 Subpart C Check: What Summer Put on Your Books, and the Clocks That Come Due Before Heating Season

Week 36. The cooling season is winding down, and with it the part of the year that generates most of a covered appliance's refrigerant additions. If your shop runs comfort cooling, the pounds you added between June and August are the pounds that will define 2026 on that appliance's ledger. Four months remain, and for most rooftop units and split systems those four months add a fraction of what the summer did.

That changes what a Q3 check is for. The Q1 self-audit asked whether the records existed. The mid-year audit asked whether they'd survive an inspector. The Q3 check asks a narrower, more time-bound question: which clocks did summer start, which clocks from the first half of the year mature this month, and which numbers are now close enough to final that a decision is due before Q4?

Six checks. Q3 closes September 30. Run them before it does.

Check 1 — The Repair Clocks August Started

Peak-season additions produce peak-season exceedances, and every exceedance starts the same clock. § 84.106(d) gives the owner or operator 30 days "of when refrigerant is added to a refrigerant-containing appliance exceeding the applicable leak rate" to identify and repair the leaks — 120 days only if an industrial process shutdown is required. An exceedance discovered on an August 20 service call has a repair-and-initial-test deadline of September 19. A clock that started the last week of August runs out the last week of September. These are the clocks most likely to be open right now, and the ones most likely to have been started by a tech who didn't realize the top-off he logged was an exceedance.

Pull every refrigerant addition from June 1 forward. For each, confirm the leak rate was calculated at the time of the addition (§ 84.106(b) requires it "every time refrigerant is added"), then sort the exceedances by date. Every one of them should be in one of the three states the mid-year post laid out — closed cleanly, closed by a documented extension, or closed by a documented retrofit or retirement plan. The ones from late August are still open by definition. Those need a repair, an initial verification test, and a follow-up test, and the follow-up has its own clock:

An initial test passed on September 15 puts the follow-up due by September 25 — unless the repair required evacuating the system, in which case the 10 days run from the day it's back at normal operating conditions. On a cooling-only appliance in late September, "normal operating characteristics and conditions" can become a real question: if the building doesn't call for cooling, the system may not reach normal load. The rule anticipates it — where a follow-up test at normal conditions is "unsafe to be present or otherwise impossible," the test "must, where practicable, be conducted prior to the system returning to normal operating characteristics and conditions." Document the reasoning on the ticket. A follow-up test performed at reduced load with the reason written down is a record; a follow-up test postponed until next May is a gap.

One more sentence from § 84.106(d)(2) matters for how you read the fall. Leak repairs "will be presumed to be successful if, over the 12-month period after the date of a successful follow-up verification test, there is no further refrigerant addition" or the required inspections find nothing. A quiet heating season on a repaired appliance is not evidence of nothing — it's the first months of that presumption accruing. Keep the follow-up test date findable; it's the anchor for the next check too.

Check 2 — Inspection Dates Anchored to This Year's Verification Tests

This is the check most shops miss, because the inspection schedule under § 84.106(g) runs on the appliance's own calendar, not the shop's. Once an appliance has exceeded its threshold and the repair has verified, the leak-inspection cadence is anchored to the date of the successful follow-up verification test — and it keeps running until the appliance proves itself clean.

Commercial refrigeration and industrial process appliances between 15 and 500 pounds, and every comfort cooling appliance regardless of charge, are on the annual version of the same rule under (g)(1)(ii) and (iii) — once per year after the follow-up test, until a clean year. We walked the schedule and its exit in detail here. The Q3 job is arithmetic:

1. List every successful follow-up verification test recorded since January 1, with the appliance's category and full charge.
2. For each 500-pound-plus commercial or industrial appliance, add three months to the test date, and keep adding: a follow-up test passed on May 14 puts inspections due August 14, November 14, February 14, and May 14 before the four-clean-quarters exit can be claimed. If the August one didn't happen, that's a finding today.
3. For everything else, add one year. A May 14 follow-up test means an inspection due by May 14, 2027 — put it on the calendar now, because next May's version of you will be in the middle of spring startups.

Every inspection has to leave the § 84.106(l)(5) record behind: "the date of inspection, the method(s) used to conduct the leak inspection, a list of the location of each leak that was identified, and a certification that all visible and accessible parts of the refrigerant-containing appliance were inspected." A routine fall maintenance visit that happened to include a leak check is not an inspection record unless it says those four things. If a Q4 inspection date falls on an appliance your techs will be visiting for a heating-season tune-up anyway, build the (l)(5) fields into that ticket now rather than discovering the visit didn't count in January.

Check 3 — The H1 Exceedances Whose Outer Clocks Mature in Q3

Three deadlines in § 84.106 are measured in months, not days, and for exceedances that happened in February, March, and April, those deadlines land in September and October. None of them appear on a 30-day repair calendar. All of them are hard.

The 180-day parts cap. An extension for parts that couldn't be delivered in 30 days is permitted under § 84.106(f)(1)(iii) "up to 30 days after receiving delivery of the necessary components, not to exceed 180 days (or 270 days if an industrial process shutdown is required) from the date the refrigerant-containing appliance exceeded the applicable leak rate." For an exceedance on March 10, that outer cap is September 6 — already passed as this posts. Every parts extension filed in Q1 has a cap somewhere in Q3. If the components arrived and the repair isn't verified, the extension has run out regardless of what the estimated completion date said. If they still haven't arrived, the 180 days still ran out. Document where it stands.

The 180-day relief window. If a retrofit or retirement plan was written because an appliance wouldn't come below its threshold, § 84.106(h)(5)(ii) lets the owner or operator ask EPA to be relieved of the retrofit or retirement obligation — but only "if the owner or operator can establish within 180 days of the plan's date that the refrigerant-containing appliance no longer exceeds the applicable leak rate" and agrees in writing to repair all identified leaks within one year of the plan's date. A plan dated April 8 closes that window on October 5. Any appliance that got a plan in Q1 or Q2 and has since been repaired and verified is a candidate — and the window to say so is closing.

The seven-month extension window. Extensions to the one-year retrofit or retirement schedule under § 84.106(i) "must be submitted to EPA electronically, using the Agency's applicable reporting platform, within seven months of discovering the refrigerant-containing appliance exceeded the applicable leak rate." Seven months from a February 15 exceedance is September 15. From March 10, October 10. If a retrofit or replacement scheduled under an H1 plan is going to run past its one-year date — custom equipment, a long lead time, a landlord who hasn't signed off — the request has to be in before the seven-month mark, and it needs the full contents list in (i): appliance identification, leak rate and method, exceedance date, leak locations, repairs finished to date, the plan to finish, the reasons more than a year is needed, and an authorized official's signature.

Build a table with one row per H1 exceedance: exceedance date, plan date if any, and the three computed dates. Most rows will have nothing due — most exceedances get repaired inside 30 days and never touch (f), (h), or (i). The rows that do have something due are the rows an inspector would ask about first, because they're the ones where the shop asked for more time.

Check 4 — Read the Chronic-Leaker Report Backwards

The calendar-year total is the number the mid-year audit told you to sort high to low in June. In September that same number means something different, because the trajectory is mostly known. § 84.106(j) is one sentence:

Take a 60-pound R-410A rooftop unit — comfort cooling, 10% threshold. It took 14 pounds in March, 22 in June, and 30 in August. Each of those additions was an exceedance on its own: run through the annualizing method, the March addition (first on record, so the 365-day substitution applies) comes out at 23.3%, the June addition 90 days later at 148.7%, and the August addition 71 days after that at 257.0%. The calendar-year total is 66 pounds on a 60-pound charge — 110%. It is not a chronic leaker today. A single 9-pound top-off between now and December 31 makes it one, and the report is due March 1, 2027 whether the ninth pound goes in on a warm October afternoon or during a heating-season call on a dual-function heat pump.

That's the Q3 reframe: for anything above roughly 100% of charge year-to-date, the question is no longer "will it get there" but "what will the report say." So read the twelve § 84.106(m)(4) fields as a to-do list rather than a form:

• (v) Annual percent refrigerant loss, (vi) dates of refrigerant addition, (vii) amounts added — these are your ledger. If the ledger is per-appliance and complete, they fill themselves. If two techs' additions live on two separate tickets that never met, this is the month to reconcile them.
• (viii) Date of last successful follow-up verification test — the report asks it directly. An appliance that hits 125% with a verified repair on file reads very differently from one that hits 125% with this field blank. A repair completed and verified in September is the difference.
• (ix) Explanation of cause and (x) description of repair actions taken — written from records, not memory. The August ticket that says "topped off" with no leak location is the ticket that makes (ix) impossible to answer honestly in February.
• (xi) Whether a retrofit or retirement plan has been developed and the anticipated date — if the honest answer for a 110% appliance is that repair isn't going to hold, the three-door decision belongs in Q3, so the plan exists before the year closes rather than after the report is due.

For appliances between roughly 75% and 100%, the Q3 action is a leak inspection and repair now, while the appliance is still running under load and the leak is findable — not because the rule requires it at that number, but because a documented September repair is the only thing that changes the trajectory before the heating season shuts the cooling-only units down and freezes the ledger where it stands. The chronic-leaker filing walkthrough covers the submission itself; the Q3 check is about what the submission will contain.

At 110% of charge in September, the question isn't whether the appliance will be reported. It's what the twelve fields will say when it is.

Check 5 — Plans Written in Q1 Finish in Q1

Every § 84.106(h) retrofit or retirement plan carries a one-year completion clock: "all work performed in accordance with the plan must be finished within one year of the plan's date." A plan dated April 8, 2026 has to be finished by April 8, 2027. Q3 is where that stops being a future problem. A retire-and-replace under a Q1 plan means a new appliance on order, and equipment lead times in 2026 are what they are — a rooftop unit ordered in October for a February install is a normal timeline; one ordered in January is not.

Two details in (h) get missed on the completion side. First, § 84.106(h)(4): "All identified leaks must be repaired as part of any retrofit under such a plan." A retrofit that converts the refrigerant and leaves a known leak unrepaired hasn't completed the plan. Second, the plan itself is a required record under § 84.106(l)(8), and § 84.106(h)(3) says where it lives: "accessible at the site of the refrigerant-containing appliance in paper copy or electronic format, and available for EPA inspection upon request." If the plan was drafted at the office in March and the appliance is on a roof in another county, confirm a copy is actually retrievable at the site, not just in your cloud folder.

If the completion date is going to slip, Check 3 already told you the deadline for saying so: the (i) request goes in within seven months of discovering the exceedance, not seven months of realizing the schedule is in trouble.

Check 6 — Set Up the Fall Before It Starts

Three things the fall will ask of your records, all of which are easier to arrange in September than to reconstruct in November.

Fall pumpdowns and the seasonal variance you'll want in spring. The § 84.102 definition of seasonal variance requires "the removal of refrigerant from an appliance due to a change in ambient conditions caused by a change in season, followed by the subsequent addition of an amount that is less than or equal to the amount of refrigerant removed." The spring exclusion only exists if the fall removal was recorded — pounds recovered, date, appliance — and § 84.106(l)(12) requires the owner or operator to keep records "stating that they are using the seasonal variance flexibility and documenting the amount added and removed." Any tech doing a fall pumpdown on a covered appliance in October or November needs to weigh what comes out and write it down, or next April's addition is a leak-rate calculation, full stop.

Appliance files for everything installed or retired this summer. Every retire-and-replace that happened in June, July, or August created two records. The retired appliance's § 84.106(l)(1) file has to survive "until three years after the appliance is retired," so the retirement date needs to be in it and the file needs a home that outlives the customer relationship. The new appliance needs its own (l)(1) file "upon installation" — owner or operator, address, full charge and the method used to determine it, and the date of installation. Summer installs done at speed are the ones most likely to be missing a full-charge method.

The January 1, 2027 automatic-leak-detection date. § 84.108 applies to commercial refrigeration and industrial process refrigeration appliances with a full charge of 1,500 pounds or more. Under § 84.108(b)(2), any such appliance installed on or after January 1, 2017 and before January 1, 2026 must have an automatic leak detection system in use by January 1, 2027; one installed this year needed it within 30 days of installation under (b)(1). If any account in your book is a supermarket rack or a cold-storage system at that scale, the installation lead time is Q4's problem and the confirmation that it's handled is Q3's.

What the Q3 Output Looks Like

The output of this check is a dated table, one row per covered appliance that had any activity this year, with the computed dates next to the recorded ones:

Keep it. The Q1 2027 version of this table is the same rows with the March 1 report status filled in.

The Year Closes in Four Months

2026 is the first calendar year under § 84.106, which makes March 1, 2027 the first time any owner or operator files a Subpart C chronic-leaker report — and the first time the calendar-year totals on your books become a document EPA reads. The Q1 audit built the records. The mid-year audit tested them. This one finds the clocks. Six checks, four weeks left in the quarter, and every one of the dates above is computable from records you already have.