Manual J calculator · AZ
Manual J load calculation for Arizona.
Run an ACCA Manual J 8th Edition residential load calculation with climate context pre-loaded for Arizona — ASHRAE design temperatures for 4 top metros, IECC 2018 (varies by jurisdiction — no statewide adoption), and AZ ROC licensing context already accounted for in the assumption defaults.
Pre-loaded scenario
Phoenix, AZ (Maricopa County) · ASHRAE zone 2B · winter 99% DB 39°F · summer 0.4% DB 109°F · MCWB 71°F.
ASHRAE 169-2021 · ACCA MJ8 §6
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01 · ASHRAE design conditions
Top 4 metros in Arizona — design temperatures used in Manual J.
These are the ASHRAE 99% heating and 0.4% cooling design temperatures — the values Manual J uses for the design day, not the absolute extremes. Equipment sized to these conditions undersizes for ~35 hours per year in summer (acceptable per ACCA convention) and ~22 hours per year in winter.
| Metro | County | Zone | Winter 99% DB | Summer 0.4% DB | MCWB |
|---|---|---|---|---|---|
| Phoenix | Maricopa County | 2B | 39°F | 109°F | 71°F |
| Tucson | Pima County | 2B | 34°F | 104°F | 67°F |
| Mesa | Maricopa County | 2B | 39°F | 109°F | 71°F |
| Flagstaff | Coconino County | 5B | 4°F | 82°F | 58°F |
Source: ASHRAE 169-2021 (republished in EERE Building America Guide 7.3, public domain). DB = dry-bulb. MCWB = mean coincident wet-bulb at the 0.4% cooling design hour.
02 · Energy code
Arizona energy code: IECC 2018 (varies by jurisdiction — no statewide adoption)
Adopted 2018. Manual J load-calc documentation requirements flow from the state energy code; verify your specific AHJ’s submittal rules before relying on the baseline.
- Arizona has no statewide residential energy code — adoption is at city/county level. Phoenix, Tempe, Tucson, and most metro jurisdictions have adopted IECC 2018 or 2021; rural counties may still operate without a residential energy code.
- Always confirm with the local building department before assuming any IECC edition applies to a specific job site.
Source: DOE Building Energy Codes Program — Arizona status · verified 2024-10-01
03 · Arizona HVAC labor data
BLS wages and employment for HVAC mechanics in Arizona.
These are state-level wages for occupation code 49-9021 — Heating, Air Conditioning, and Refrigeration Mechanics and Installers — from the most recent BLS Occupational Employment and Wage Statistics release.
- Median hourly wage
- $24.30
- Mean annual wage
- $53,180
- Employment estimate
- 9,870
Source: BLS OEWS May 2023, SOC 49-9021 (state-level) · released 2024-04-03. Loaded labor rates billed to customers typically run 2.5–3.5× the technician wage after overhead.
04 · License & permit
HVAC licensing in Arizona: AZ ROC.
State-level HVAC contractor licensing is administered by the Arizona Registrar of Contractors. Licenses renew every 2 years.
License types
- C-39 Air Conditioning and Refrigeration (residential, commercial)
- K-39 Dual License (residential + commercial AC)
- L-39 Specialty AC license (≤25 tons)
Permits
Most Arizona cities require a mechanical permit for new HVAC installations and any change-out involving refrigerant lines or electrical service modifications. Permits are issued by city building safety departments.
Replacement permit: typically required.
Phoenix and Tucson use online permit portals; outlying Maricopa County areas defer to the county. Always pull the permit before purchasing equipment — desert-rated condensing units may have additional product-listing requirements.
05 · FAQ
Common Manual J questions for Arizona contractors.
+How hot does Phoenix get for Manual J sizing?
Phoenix's ASHRAE 0.4% summer DB is 109°F with a 71°F mean coincident wet-bulb — the highest sensible cooling load in any major U.S. metro. Equipment selected with Manual S in Phoenix must verify rated capacity at the 105°F+ outdoor temp, not just AHRI 95°F rating conditions.
+Why does Manual J differ so much between Phoenix and Flagstaff?
Phoenix is zone 2B (hot-dry), Flagstaff is zone 5B (cool-dry) — both in Arizona, both with low humidity, but separated by 5,000 ft of elevation. Flagstaff's heating-dominant Manual J typically delivers 35–40 BTU/hr per square foot in winter; Phoenix's cooling-dominant Manual J runs 25–30 BTU/hr/sqft in summer. The same house design needs a completely different system.
+Do I need a C-39 license to do HVAC work in Arizona?
Yes for any project over $1,000 (the unlicensed handyman threshold). C-39 is the most common residential HVAC license. K-39 is the dual residential/commercial. L-39 limits the contractor to ≤25 tons cooling capacity — fine for most residential, restrictive for light commercial.
+Why is dry-bulb so much more important than wet-bulb in Arizona?
Arizona's design wet-bulb sits at 67–71°F — lower than most of the country despite the high temperatures. The sensible-to-total ratio in Manual J for Phoenix runs 0.85+ (sensible-dominant). Equipment selected on total capacity alone over-cools and short-cycles; selection should target the sensible load.
+Does Arizona require Manual J for permit?
Per-jurisdiction. Phoenix and Tempe accept Manual J output as part of the energy compliance submittal under their adopted IECC editions; rural counties may not require it at all. BuildSolver's audit trail is sufficient for most metro AHJs that do require documentation.
+What's the average HVAC technician wage in Arizona?
BLS OEWS May 2023 reports $24.30/hr median for Arizona HVAC mechanics and installers — about $53,180 annual mean — close to the national median.
Try a Arizona load calculation now.
The chat will ask follow-up questions like an experienced engineer — square footage, construction type, window count, insulation level — and run the Manual J on your inputs with Arizona’s ASHRAE design temperatures applied automatically. About 90 seconds end to end.
Start Arizona calculationRelated · same climate zone
Other states with similar ASHRAE climate zones.
Manual J assumptions for infiltration, latent share, and design temperatures behave similarly across states that share an ASHRAE zone. The pages below carry the same procedural defaults with their own local design temps and licensing context.
Data last reviewed 2026-05-19 · underlying sources as of 2024-04-03