Comparison

HVAC School vs HVAC 3D Design Learning Studio

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

HVAC School

This app serves as a comprehensive resource for HVAC technicians, offering a podcast, tech tip articles, and interactive calculators. It aims to enhance knowledge of HVAC theory, industry updates, and essential mathematics for both current and aspiring professionals.

Highlights
  • HVAC School podcast episodes
  • Tech tip articles by professionals
  • Interactive HVAC equation calculators
  • Industry knowledge and theory
  • Up-to-date industry information
Features
Read full description

The app that helps you remember some things you forgot along the way, as well as helps you remember some things you forgot to know in the first place. For all current and aspiring HVAC technicians: HVAC School is the premiere source for knowledge and success in the HVAC industry. With this app you can: * Listen to all episodes of the HVAC School podcast, a podcast committed to bringing you relevant and up to date knowledge of the HVAC industry and what it means to be an HVAC technician. * Read tech tip articles written by industry professionals on various topics to help build your knowledge base and understanding of HVAC theory * Interact with calculators that employ common HVAC equations to help build your understanding of important HVAC mathematics

About

HVAC 3D Design Learning Studio

Features
Read full description

HVAC3D is a professional-grade HVAC reference and learning tool built around an interactive 3D model of a fully engineered 3-story commercial building. Tap any component — AHU, chiller, VAV box, DDC controller — to see its specs, code references, and system connections in real time. Version 3.0 adds six major tools: Duct Sizing Calculator — SMACNA equal-friction and velocity method sizing for round and rectangular ducts, with live ASHRAE velocity and friction limit checking. ASHRAE 62.1 Ventilation Calculator — Multi-zone Ventilation Rate Procedure (VRP) with space-type lookup from Table 6-1, zone-by-zone breathing zone OA, and system outdoor air (Vot) output. Hydronic Pipe Sizing — Darcy-Weisbach pipe sizing for chilled water, hot water, and condenser water. Input GPM, tons, or MBH and get a recommended pipe size with Reynolds number and friction factor. Sequence of Operations Library — Six complete BAS control sequences: Economizer, DCV, Supply Air Temperature Reset, Morning Warm-Up, Chiller Staging, and VAV Box Control — all per ASHRAE Guideline 36. A2L Refrigerant Safety Guide — 2025 installation requirements for R-454B and R-32 including detector placement, machinery room ventilation, charge limits, and EPA AIM Act compliance per ASHRAE 15-2022. PDF Export — Share the Equipment Schedule, ASHRAE 180 Inspection Checklist, and Calc Sheets as formatted PDFs via AirDrop, email, or Files. The full feature set includes: 3D interactive building model • Floor-by-floor and system filtering • Component info panels with code citations • Learning Hub (Quiz, Glossary, Fault Simulator, Load Calculator, Guided Tour, Violations, Inspection Checklist) • Psychrometric Chart (SI + IP) • System Design Wizard • Refrigerant Phase-Out Guide • Floor Plans • Riser Diagrams • Equipment Schedule • Operation Matrix • Gallery of 49 professional HVAC diagrams Standards covered: ASHRAE 62.1 / 90.1 / 15 / 180 / Guideline 36 • IMC • SMACNA • ACCA Manual J • NFPA 90A / 92 / 96 • EPA AIM Act For educational and reference use only. All system designs must be reviewed and stamped by a licensed mechanical engineer before implementation. ASHRAE, SMACNA, NFPA, ACCA, ANSI, ASME, IMC, IBC, UL, and EPA are trademarks or registered trademarks of their respective organizations. HVAC3D is an independent educational application and is not affiliated with, endorsed by, or sponsored by any of these organizations. All standard references are cited for informational purposes only and do not constitute legal or engineering advice.

Screenshots

HVAC School4 screens
HVAC 3D Design Learning Studio4 screens

Verdict

The call

The clearest difference is price: HVAC School at Free against HVAC 3D Design Learning Studio's $9.99. HVAC School also leads on iOS requirement (13.4 vs 16.0). On update cadence, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

HVAC School is free to download; HVAC 3D Design Learning Studio costs $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

HVAC School ships an update every 5 weeks, HVAC 3D Design Learning Studio every 3 weeks. The most recent releases landed on November 2, 2026 and November 9, 2026 respectively.

Scorecard2 real differences · 8 level
HVAC School versus HVAC 3D Design Learning Studio: the parameters behind the verdict, then further details
ParameterHVAC SchoolHVAC 3D Design Learning Studio
PriceFree — better$9.99
Rating4.8 (85 ratings) — better—
Positive reviews82.8% of reviews—
Number of ratings85 — better—
Update frequencyEvery 5 weeksEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.4 — better16.0
Further details — not scored
Size30 MB207 MB
Age rating12+4+
DeveloperKalos Services Inc.Yuhsiu Lai

In-app purchases

None

HVAC School

No in-app purchases

None

HVAC 3D Design Learning Studio

No in-app purchases

Questions

Is HVAC School free?
HVAC School is free to download, with no in-app purchases.
Is HVAC 3D Design Learning Studio free?
HVAC 3D Design Learning Studio costs $9.99, with no in-app purchases.
Do HVAC School or HVAC 3D Design Learning Studio have ads?
Neither HVAC School nor HVAC 3D Design Learning Studio shows ads.
Which is updated more often, HVAC School or HVAC 3D Design Learning Studio?
HVAC School ships an update every 5 weeks, and HVAC 3D Design Learning Studio every 3 weeks. Most recently, HVAC School was updated on November 2, 2026 and HVAC 3D Design Learning Studio on November 9, 2026.

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