Ventilation, Heating, Air-Conditioning & Commercial Refrigeration Equipment Manufacturing — U.S. Industry-Group Primer

NAICS 2022 code 3334. NAICS = North American Industry Classification System, the standard code set U.S. statistical agencies use to define industries. This is a four-digit "industry group."

A Histometrics rollup primer for public-market and private investors.

---

1. Overview

This industry group is the factory floor of American climate control: the makers of the machines that move air, heat buildings and water, cool and refrigerate space, and clean the air inside homes, offices, stores, factories, hospitals, data centers, and cold-storage warehouses. In shorthand it is the equipment-manufacturing core of HVACR — heating, ventilation, air conditioning, and refrigeration. It excludes the contractors who install the gear and the distributors who move it (those sit in adjacent codes), so this is about the people who make the boxes, not the people who fit them.

For an investor, the one thing to know up front is structural, not economic: at the four-digit level this group contains exactly one child industry, and it is identical to that child. See Section 2.

Two things in the near-term picture have changed since this page was last written, and both flow up from the child. First, the residential volume cycle has turned down hard even as the structural story stays intact: U.S. shipments of central air conditioners and air-source heat pumps through November 2025 were 7,341,285 units, down 19.9% year over year — straight AC down 25.6%, heat pumps down 12.1% [10]. Second, the federal incentive and mandate regime has retreated: the Section 25C consumer credit terminated for equipment placed in service after December 31, 2025 [11], the all-condensing boiler proposal was withdrawn [12], and the fan-efficiency standard was withdrawn with DOE now proposing to drop fans and blowers as "covered equipment" entirely [13]. A defensive, replacement-anchored sector is not a flat one.

---

2. What's inside — one child, so the level equals the child

NAICS is a nested system: each four-digit "industry group" splits into one or more five-digit "industries." Industry group 3334 has a single child — 33341, Ventilation, Heating, Air-Conditioning, and Commercial Refrigeration Equipment Manufacturing. Because there is nothing else at this level, 3334 and 33341 are one and the same population of factories, firms, shipments, and workers. Every figure below is therefore shared with 33341, and the detail — who is public versus private, where the growth and the regulation sit — is covered in full in the 33341 primer, which this page does not duplicate.

What the four-digit page can usefully carry down from the child is the shape of the split one level further in, because that split is where all the variation in this group lives. 33341 divides into three six-digit industries that share end-markets but behave very differently [3]:

Two consequences matter at this level. First, the "warm-air furnace" boundary splits heating across two of the three — forced-air furnaces sit with the AC makers in 333415 while water-based boilers sit in 333414 — which is why the big furnace/HVAC names are not in the heating industry at all [3]. Second, concentration falls when you zoom out to 3334/33341: the level's CR4 of 22% sits below two of its three grandchildren, because pooling three sub-industries with three different sets of leaders dilutes any one firm's share [1,3].

A boundary caution the children now make in unison. Published "HVAC market," "industrial fans market," and "boiler market" figures do not map to these codes: they mix consumption with production and fold in contractors, distributors, controls, and services that sit elsewhere in NAICS, often on a global rather than domestic basis. Any market share, margin, or transaction multiple applied at this level should be traced back to which code — and which activity — it actually measures [3].

---

3. How big it is

Federal statistics for this four-digit industry group (our ground-truth figures) [1][2]:

Because the group has one child, these numbers are identical to 33341's — the four-digit and five-digit rollups are the same aggregate. Below that, the child reports that its three pieces reconcile cleanly: their establishments sum to exactly 1,685 and their employment to exactly 147,794, with firm counts the only exception (the three total 1,404 against 1,388 here, a normal Census artifact when one company operates in more than one sub-industry) [3]. The U.S. Small Business Administration thresholds here are 1,250 employees for the AC/refrigeration sub-industry and 500 for the other two [4], so the great majority of the 1,388 firms count as small businesses.

Undercount / read-carefully caveat. This is establishment-based factory manufacturing, so it is not undercounted the way government-dominated or sole-proprietor/gig industries are — there are no small-owner or individual-operator blind spots to flag, and the Census captures it well. But the ~$55B headline understates the sector's true economic footprint for reasons detailed in the 33341 primer: it counts domestic production, not U.S. consumption (a large and rising share of AC units, boilers, fans, and filters is imported); the leaders are diversified multinationals whose reported revenue dwarfs their U.S.-factory output classified here (Carrier alone booked $21.7 billion in 2025 sales [5] — roughly two-fifths of this group's entire domestic shipments — and Trane roughly $21.3 billion [6]); and distribution, installation, and controls sit in other codes (thermostats and environmental controls are 334512). Note also that the AHRI shipment series the trade watches most closely includes imported equipment, so it is not comparable with this figure either [10]. Independent "HVAC market" estimates run far larger because they use consumption-based, service-inclusive, or global scopes — treat those as directional, not comparable with this federal domestic-production figure.

---

4. Investable universe — where value concentrates

Since the group equals 33341, the investability picture is 33341's, and its defining feature is that clean public exposure is wildly uneven across the child's three sub-industries. Roughly three-quarters of the group's shipments — and essentially all of its liquid, listed pure-plays — sit in the air-conditioning and commercial-refrigeration sub-industry (333415): Carrier (CARR), Trane Technologies (TT), Lennox (LII), and AAON, whose year-end 2025 backlog reached $1.83 billion against $867 million a year earlier on data-center cooling orders [8], plus Johnson Controls (JCI) as a buildings/controls play after selling residential HVAC to Bosch [9]. Downstream, the distributor Watsco (WSO) and the mechanical contractor Comfort Systems USA (FIX) are often the most direct public route to U.S. replacement and service demand, though both sit in adjacent codes [3].

The fan/air-purification sub-industry (333413) still has no U.S.-listed pure play; its purest operators — Greenheck, Twin City Fan, New York Blower, Camfil and peers — are private or family/ESOP-owned, and public exposure comes only as segments inside diversified or foreign-listed parents such as CECO, Donaldson, Ingersoll Rand, Munters, and Systemair [3]. Baker Hughes joined that list by picking up Howden's industrial fans and blowers when it completed the Chart Industries acquisition in July 2026 [18].

The revised child does, however, correct one thing this page previously implied: the hydronic-heating sub-industry (333414) carries more listed exposure than "segments inside diversified parents" suggested, even though there is still no pure play. A.O. Smith now separately discloses North American boilers and parts of about $281 million in 2025, up 8%, and SPX Technologies books roughly $585 million of hydronic, electrical-heating, and ventilation revenue inside a $1.52 billion HVAC segment [15]; HNI's residential building products segment (hearth) ran $675 million of sales at $122 million of operating income, an 18% margin; and Burnham Holdings offers direct but illiquid exposure over the counter (OTC: BURCA, $270 million 2024 sales) with the disclosure limits that implies [16]. The concentrated boiler assets — Mestek, Bradford White/Laars, ECR, Raypak — remain private [3]. Tickers, scale, and the full public/private map are in Section 4 of the 33341 primer.

---

5. How the money works

This is durable-goods manufacturing, and its economics are read through manufacturing levers — not utility rate base, real-estate cash flow, or mining cost curves. The recurring levers: a deep replacement base (equipment lasts ~15–30 years and fails on its own schedule, giving the sector a recurring, weather-driven demand floor — the heating sub-industry puts roughly two-thirds of demand on replacement, the AC sub-industry says "most" [3]); volume × the price/cost spread over copper, aluminum, steel, and cast iron, where pass-through is real but lagged (copper rose more than 50% from 2020 to 2023 [19], and the producer price index for heating equipment climbed from 321.6 in January 2020 to 500.5 in June 2026, about 56% [23], while Lennox's 2025 Home Comfort volume fell 17% against +10% of price and mix [7]); capacity utilization against high fixed costs; a higher-margin aftermarket (parts, controls, service, and scheduled replacement filters) that smooths the equipment cycle — Carrier reports 28% of 2025 sales from parts and service, and Trane splits 2025 revenue into $13.98 billion of product against $7.34 billion of service [5,6]; backlog on the engineered commercial and data-center side, which should be read for cancellation rights and escalation clauses rather than taken at face value [8]; and a steady mix shift up toward higher-efficiency, higher-priced units. The two-step manufacturer → distributor → contractor channel means the installing contractor usually picks the brand, while commercial and applied work runs through consulting engineers and manufacturers' representatives instead [3].

The children now supply comparable segment margin benchmarks — Trane Americas at 21.6% adjusted EBITDA, Lennox segments at 21.8% and 23.4%, SPX HVAC at 24.5%, HNI residential building products at 18% [6,7,15,16] — but none maps cleanly to a NAICS code, since each consolidates services, controls, distribution, and foreign operations. Treat them as illustrative of engineered-equipment economics, not as an industry margin. Fully worked through in the 33341 primer.

---

6. Demand drivers

The same drivers apply to the group as to its child: the aging installed base and replacement cycle (largest and steadiest); data centers and AI, the fastest-growing new pull, hitting all three sub-industries at once — the data-center cooling market ran ~$21 billion in 2024 against a ~$55 billion 2030 projection, and Lawrence Berkeley's June 2026 update estimates data centers at 11.8% of U.S. electricity by 2030 within a 9.5%–15.3% range [20]; heat-pump electrification (a tailwind for the AC sub-industry, a structural headwind for gas boilers — natural gas was the main heating fuel in 47% of U.S. homes in 2024 against 42% for electricity, gas down from 49% in 2010 [21]); construction (rate-sensitive residential plus nonresidential); weather; regulation-forced upgrades; cold chain; and indoor air quality, emissions rules, and reshoring.

Two things are worth flagging at the group level. The near-term signal is negative, not neutral: AC and heat-pump unit shipments fell about a fifth year over year through November 2025 [10]. And the children genuinely disagree about the direction of the data-center story — the AC sub-industry treats liquid cooling as its fastest-growing slice and the source of AAON's backlog surge, while the fan sub-industry warns that rising rack densities and direct-to-chip cooling may reduce fan content per unit of computing even as facility ventilation and heat rejection grow [3,8]. Both can be true; read it as a mix shift within the data-center opportunity that moves content between sub-industries rather than a single directional bet. Detail and figures in Section 6 of the 33341 primer.

---

7. Regulation

Regulation shapes the group from two directions — efficiency/refrigerant rules on the product and environmental/safety rules that create demand — with the Department of Energy (DOE) and Environmental Protection Agency (EPA) the main federal actors. The headline items, as the child now states them:

• Refrigerants. Under the AIM Act (American Innovation and Manufacturing Act), EPA's Technology Transitions program imposed a global-warming-potential limit of 700 on residential and light-commercial AC and heat pumps beginning January 1, 2025, with covered variable-refrigerant-flow systems transitioning January 1, 2027. The industry moved to mildly flammable low-GWP "A2L" refrigerants such as R-454B (GWP ~466) and R-32 [14].
• Efficiency (AC). SEER2 (Seasonal Energy Efficiency Ratio 2) and HSPF2 minimums took effect January 1, 2023, with floors around 14.3 SEER2 in the North and 15 in the South [14].
• Efficiency (boilers and furnaces). DOE's proposed 95% AFUE (Annual Fuel Utilization Efficiency) boiler standard, which would have effectively banned non-condensing boilers, was withdrawn on January 17, 2025, leaving the 2016 standards in place. The parallel 95% AFUE furnace rule was upheld on appeal and is now the subject of a Supreme Court petition filed January 2026 — unresolved, not settled [12].
• Efficiency (fans). DOE finalized a test procedure in 2023, proposed a standard in January 2024, withdrew it in January 2025, and in May 2025 proposed dropping fans and blowers as "covered equipment" entirely; there is no federal minimum-efficiency standard in force. State and model codes plus AMCA certification keep efficiency a real market requirement anyway [13].
• Tax and trade. The One Big Beautiful Bill (signed July 4, 2025) terminated the Section 25C credit for equipment placed in service after December 31, 2025, ended 45L for homes acquired after June 30, 2026, and ended the Section 179D commercial-building deduction for construction beginning after June 30, 2026 [11]. Tariffs are now a live input-cost variable: Mexican-made HVACR equipment, the largest U.S. import source, saw effective rates jump from roughly 8% toward 25%, and Chinese compressors, motors, and control boards carry combined rates above 30% [19].

The common thread is that the federal push toward mandatory efficiency retreated in 2025–2026, while state codes, energy prices, and payback economics keep the efficiency mix-shift intact. Full timeline in Section 7 of the 33341 primer.

---

8. Consolidation

Concentration is low at this level (CR4 22%, HHI 199.4 — "unconcentrated" in antitrust terms, anything under 1,500 [1]): a long tail of specialists sits beneath a small top tier, and as Section 2 notes, the four-digit figure understates how concentrated the individual sub-industries are. That top tier has nonetheless been reshaping aggressively — Carrier's pivot to a pure-play climate company (buying Viessmann's climate business, selling commercial refrigeration to Haier at a $775 million enterprise value in October 2024), Johnson Controls' exit from residential HVAC to Bosch for $8.1 billion, completed August 2025 [9,22], Emerson's climate arm sold to Blackstone (now Copeland, valued at $14 billion in 2023) [22], plus roll-ups of boiler and industrial-air specialists — A.O. Smith/Lochinvar, SPX's hydronics platform around Weil-McLain, Ingersoll Rand's blower brands, and Baker Hughes taking on Howden via Chart in July 2026 [15,18].

The revised child also supplies this level's only public valuation benchmark: Miura's 2024 purchase of Cleaver-Brooks disclosed $573 million of revenue, $88 million of EBITDA, and a $774 million enterprise value — useful, but not a clean comparable, since Cleaver-Brooks' larger industrial boilers belong in NAICS 332410 [17]. Fragmentation plus steady aftermarket cash flow makes the sector a natural hunting ground for buy-and-build private equity and strategic tuck-ins, especially in the two privately dominated sub-industries. Deals by sub-industry in Section 8 of the 33341 primer.

---

9. Risks

The group's risks are 33341's: construction cyclicality and rate sensitivity on the new-build side, with the current downturn already visible in the roughly 20% year-over-year decline in AC and heat-pump shipments [10]; input-cost and tariff volatility (copper, aluminum, steel, and tariffed imported motors, compressors, and control boards), which is most dangerous where manufacturers carry long backlogs at fixed prices [19]; regulatory execution and whiplash (the A2L refrigerant transition's redesign, requalification, dual-inventory and training costs; deadline-driven pre-buys; and the unresolved Supreme Court furnace/water-heater case) [12,14]; loss of federal incentives heading into 2026 [11]; internal substitution running both ways — heat-pump electrification helps the AC sub-industry but structurally threatens gas boilers, while liquid cooling may shift content away from fans even as it drives AC-side backlogs [3,8]; concentration in the growth story (AAON itself warns that data-center orders are more prone to timing changes and cancellation than its traditional commercial book [8]); project execution on engineered work; product liability and safety, elevated by the refrigerant transition; labor in the plants and among installers; and import competition at the premium end. For public proxies in the fan/air and boiler sub-industries there is a further risk — the relevant business is a minority segment inside a diversified parent, and the one direct route (Burnham, OTC) trades illiquidity and reduced disclosure for purity [16]. Detail in Section 9 of the 33341 primer.

---

10. How to invest, and the outlook

Because the group equals its one child, the how-to-invest map is identical to 33341's. Public-market routes concentrate in the AC/refrigeration sub-industry: direct pure-plays (CARR, TT, LII, AAON, with JCI as a buildings/controls play) plus their distributors and installers (WSO, FIX, EME). The industrial-air theme is reachable only as segments (CECO, DCI, IR, BKR, AME; abroad Munters and Systemair), and the boiler/hearth theme as minority lines (AOS, SPXC, HNI, WTS, MOD, PNR/HAYW) with BURCA the direct-but-illiquid exception. Private-market routes are where the purest fan and boiler operators live (family/ESOP-owned), alongside active PE roll-ups of HVAC service and contractors — exposure to contracting rather than manufacturing — and corporate carve-outs of the Bosch/JCI and Haier/Carrier type. Before applying any market share, margin, or multiple, map each plant and product line to the code boundary and size the relevant exposure inside each diversified name [3]. Specific names, tickers, and scale are in Section 10 of the 33341 primer.

Outlook (forward-looking judgment). The demand backdrop into the second half of the decade is favorable and, unusually, internally hedged: a deep replacement base underpins the whole group, while data-center cooling and air-handling, indoor-air-quality and reshoring, cold-chain capacity, and heat-pump electrification pull growth — with the boiler segment's electrification headwind partly offset by the 2025 withdrawal of the all-condensing mandate. The near term is harder than this page previously implied: residential unit shipments are down roughly a fifth year over year, the 25C credit is gone, and refrigerant-transition costs are still working through prices [10,11,14]. Net: a defensive, replacement-anchored manufacturing sector with genuine secular growth optionality, currently working through a cyclical and policy-driven air pocket. For the complete treatment — the three-way internal split, the full investable universe, and the source detail — read the 33341 primer, of which this four-digit page is the one-child rollup.

---

Sources

Figures on this page are drawn from Histometrics-ingested federal statistics for NAICS 3334 (identical to its sole child 33341) and synthesized from the 33341 child primer.

1. U.S. Census Bureau, "2022 Economic Census — Concentration statistics for NAICS 3334 / 33341 (receipts ~$55.03B; firms 1,388; CR4 22%, CR8 33.5%, CR20 50%, CR50 65.4%; HHI 199.4)," 2022. (Histometrics ingested federal statistics.) https://data.census.gov/
2. U.S. Census Bureau, "County Business Patterns 2023 — NAICS 3334 / 33341 (establishments 1,685; employment 147,794; annual payroll ~$9.83B; Q1 payroll ~$2.46B)," 2023. (Histometrics ingested federal statistics.) https://data.census.gov/
3. Histometrics child primer for NAICS 33341 (source of the sub-industry split and its per-sub-industry receipts, establishments, employment and concentration — 333415 ~$40.15B, 852 establishments, 101,617 employees, CR4 30.2%, HHI 348.4; 333413 ~$8.0B, 479 establishments, 29,098 employees, CR4 19.2%, HHI 185.8; 333414 ~$6.86B, 354 establishments, 17,079 employees, CR4 25.9%, HHI 267 — plus the investable-universe, operating-model, boundary-caution, replacement-share, and diligence detail summarized here). Underlying federal figures: 2022 Economic Census and County Business Patterns 2023.
4. U.S. Small Business Administration, "Table of Small Business Size Standards — NAICS 333415 (1,250 employees); 333413 & 333414 (500 employees)," 2023. https://www.sba.gov/document/support-table-size-standards
5. Carrier Global Corporation, "Form 10-K, Fiscal Year 2025" ($21.7B sales; 72% equipment / 28% parts and service; Viessmann), 2026. https://www.sec.gov/Archives/edgar/data/1783180/000178318026000008/carr-20251231.htm
6. Trane Technologies, "Form 10-K, Fiscal Year 2025" (~$21.3B revenue; Americas $17.17B at 21.6% adjusted EBITDA margin; product $13.98B / service $7.34B), 2026. https://www.sec.gov/Archives/edgar/data/1466258/000162828026005731/tt-20251231.htm
7. Lennox International, "Form 10-K, Fiscal Year 2025" (Home Comfort $3.34B at 21.8% margin, volume −17% with +10% price/mix; Building Climate $1.85B at 23.4%), 2026. https://www.sec.gov/Archives/edgar/data/1069202/000106920226000028/lii-20251231.htm
8. AAON, Inc., "Form 10-K, Fiscal Year 2025" (backlog $1.83B vs $867M; BASX backlog +141.3%; order timing and cancellation risk; labor), 2026. https://www.sec.gov/Archives/edgar/data/824142/000082414226000005/aaon-20251231.htm
9. Johnson Controls International, "Johnson Controls Reports Q4 and FY24 Results," 2024; "Johnson Controls Completes Sale of Residential and Light Commercial HVAC Business" ($8.1B transaction, August 2025), 2025. https://www.prnewswire.com/news-releases/johnson-controls-reports-q4-and-fy24-results-initiates-fy25-guidance-302297463.html; https://www.johnsoncontrols.com/media-center/news/press-releases/2025/08/01/johnson-controls-completes-sale-of-residential-and-light-commercial-hvac-business
10. Air-Conditioning, Heating, and Refrigeration Institute (AHRI), "November 2025 Statistical Release" (U.S. shipments of central AC + air-source heat pumps 7,341,285 units, −19.9% y/y; AC 3,916,218, −25.6%; heat pumps 3,425,067, −12.1%), January 2026. https://www.ahrinet.org/sites/default/files/2026-01/November2025StatisticalRelease.pdf
11. Internal Revenue Service, "FAQs for Modification of Sections 25C, 25D, 25E, 30C, 30D, 45L, 45W, and 179D under Public Law 119-21 (One Big Beautiful Bill)" (§25C terminated after Dec 31, 2025; 45L after June 30, 2026; 179D after June 30, 2026), 2025; IRS, "Instructions for Form 5695 (2025)." https://www.irs.gov/newsroom/faqs-for-modification-of-sections-25c-25d-25e-30c-30d-45l-45w-and-179d-under-public-law-119-21-139-stat-72-july-4-2025-commonly-known-as-the-one-big-beautiful-bill-obbb; https://www.irs.gov/instructions/i5695
12. U.S. Department of Energy, "Energy Conservation Standards for Consumer Boilers — Notice of Proposed Rulemaking" (95% AFUE proposal), Aug. 14, 2023, and "Withdrawal," Jan. 17, 2025; DOE Consumer Furnace final rule (95% AFUE), Dec. 18, 2023, with petition for U.S. Supreme Court review, Jan. 2026; AHRI, "Boilers — Regulatory / Energy Efficiency" (80% AFUE minimum; 75% gas-fired steam). https://www.federalregister.gov/documents/2023/08/14/2023-16476/energy-conservation-program-energy-conservation-standards-for-consumer-boilers; https://www.federalregister.gov/documents/2025/01/17/2025-00964/energy-conservation-program-energy-conservation-standards-for-consumer-boilers; https://www.federalregister.gov/documents/2023/12/18/2023-25514/energy-conservation-program-energy-conservation-standards-for-consumer-furnaces; https://www.ahrinet.org/advocacy/regulatory/energy-efficiency/residential-products/boilers
13. U.S. Department of Energy, "Fans and Blowers" rulemaking page (test procedure 2023; standard NOPR Jan. 2024; withdrawal Jan. 2025; proposed withdrawal of covered-equipment determination May 2025; no current federal standards); AMCA International, "2025 Update on U.S. Fan-Efficiency Codes and Regulations" and "AMCA Certified Ratings Program," 2023–2026. https://www.energy.gov/cmei/buildings/fans-and-blowers; https://www.amca.org/educate/articles-and-technical-papers/amca-inmotion-articles/2025-update-on-u.s.-fan-efficiency-codes-and-regulations.html; https://www.amca.org/certify/
14. U.S. Environmental Protection Agency, "Technology Transitions: HFC Restrictions by Sector" (GWP ≤700 for residential/light-commercial AC and heat pumps from Jan. 1, 2025; VRF Jan. 1, 2027); U.S. Department of Energy, "Purchasing Energy-Efficient Residential Central Air Conditioners" (SEER2/HSPF2 effective Jan. 1, 2023); Lennox, "2025–2026 SEER2 Standards and New Refrigerants" (floors 14.3 North / 15 South); National Refrigeration, "The Shift to R-454B Refrigerant" (GWP ~466), 2025. https://www.epa.gov/hfcs/technology-transitions-hfc-restrictions-sector; https://www.energy.gov/cmei/femp/purchasing-energy-efficient-residential-central-air-conditioners; https://www.lennox.com/residential/lennox-life/consumer/new-hvac-refrigerant-2025; https://nhvac.com/the-shift-to-r-454b-refrigerant-a-guide-for-home-and-business-owners/
15. SPX Technologies, Inc., "Form 10-K, Fiscal Year 2025" (HVAC segment $1.518B revenue and $372.6M segment income, 24.5%; hydronic/electrical heating/ventilation $585.3M; Weil-McLain, Patterson-Kelley, Sigma & Omega), 2026; A.O. Smith Corporation, "Form 10-K, Fiscal Year 2025" (North America boilers & parts $281.0M, +8%; N.A. segment $2.984B), 2026; A.O. Smith, "A.O. Smith to acquire Lochinvar Corporation," 2011. https://www.sec.gov/Archives/edgar/data/88205/000008820526000008/spxc-20251231.htm; https://www.sec.gov/Archives/edgar/data/91142/000009114226000008/aos-20251231.htm; https://investor.aosmith.com/news-releases/news-release-details/o-smith-acquire-lochinvar-corporation
16. HNI Corporation, "Form 10-K, Fiscal Year 2025" (residential building products segment $674.9M sales, $121.8M operating income), 2026; Burnham Holdings, Inc., "2024 Annual Report" ($270.2M sales; OTC: BURCA), 2025. https://www.sec.gov/Archives/edgar/data/48287/000004828726000084/hni-20260103.htm; https://www.burnhamholdings.com/wp-content/uploads/2025/03/2024-Annual-Report-with-Insert-1.pdf
17. Miura Co., Ltd., "Announcement of Cleaver-Brooks Acquisition" ($573M revenue, $88M EBITDA, $774M enterprise value), March 2024. https://www.miuraz.co.jp/en/investors/pdf/press_release/20240329_en.pdf
18. Baker Hughes Company, "Completion of Chart Industries Acquisition," Form 8-K, July 2026; Ingersoll Rand Inc., "Ingersoll Rand Completes Acquisition of Roots from Chart Industries," 2023. https://www.sec.gov/Archives/edgar/data/1701605/000119312526305477/d105425dex991.htm; https://investors.irco.com/news/
19. ACCA HVAC Blog, "HVAC tariffs: what contractors can do about prices going up," and Money.com, "What's Causing HVAC Prices to Rise in 2026" (copper +50% 2020–23; Mexico tariff ~8%→25%; Chinese components above 30%), 2025–2026. https://hvac-blog.acca.org/hvac-tariffs-what-contractors-can-do-about-prices-going-up/; https://money.com/whats-causing-hvac-prices-to-rise-in-2026-and-how-much-more-you-should-expect-to-pay/
20. IndustryARC / Grand View Research, "Data Center (Liquid) Cooling Market Size & Forecast" (~$21B 2024 → ~$55B 2030), 2024–2025; U.S. Department of Energy and Lawrence Berkeley National Laboratory, "Report on Data Center Electricity Demand" (176 TWh / 4.4% in 2023; 325–580 TWh by 2028), 2024; Lawrence Berkeley National Laboratory, "United States Data Center Energy Usage 2025 Update" (11.8% of U.S. electricity by 2030; range 9.5%–15.3%), June 2026. https://www.industryarc.com/Research/Data-Center-Liquid-Cooling-Market-Research-500580; https://www.energy.gov/articles/doe-releases-new-report-evaluating-increase-electricity-demand-data-centers; https://eta-publications.lbl.gov/publications/united-states-data-center-energy-2025
21. U.S. Energy Information Administration, "Heating-Fuel Use in U.S. Homes" (47% natural gas, 42% electricity in 2024; gas down from 49% in 2010), 2024; "Air conditioning in nearly 90% of U.S. homes" (RECS 2020), 2022. https://www.eia.gov/todayinenergy/detail.php/detail.php?id=66324; https://www.eia.gov/todayinenergy/detail.php?id=52558
22. HPAC Engineering, "Blackstone Completes $14B Acquisition of Emerson Climate Technologies (now Copeland)," 2023; Carrier Global, "Carrier Completes Sale of Its Commercial Refrigeration Business to Haier" ($775M enterprise value, October 2024); BuildOps, "North American HVAC Equipment Market by Manufacturer & Market Share," 2025–2026. https://www.hpac.com/technology/article/21267262/blackstone-completes-14b-acquisition-of-emerson-climate-technologies; https://www.carrier.com/commercial-refrigeration/en/eu/news/news-article/carrier-completes-sale-of-its-commercial-refrigeration-business-to-haier.html; https://buildops.com/resources/north-american-hvac-equipment-market-chart
23. U.S. Bureau of Labor Statistics, "Producer Price Index — Heating Equipment (except Warm Air Furnaces) Manufacturing (PCU333414333414)" via FRED (321.6 in Jan. 2020 to 500.5 in June 2026, ~56%). https://fred.stlouisfed.org/data/PCU333414333414