# HVAC 3D Design Learning Studio — Interactive 3D HVAC Reference > Interactive 3D HVAC Reference (iPhone/iPad app by Yuhsiu Lai.) - Source: https://appshunter.io/ios/app/hvac-3d-design-learning-studio/id6766627551 (this page in markdown: same URL + `.md`) - Developer: [Yuhsiu Lai](https://appshunter.io/developer/433114647) - Category: Education, Reference - Price: $6.99 - Age rating: 4+ - Requires: iOS 16.0 · 207 MB - Languages: English - Released: 2026-05-05 - Data updated: 2026-08-31 - User reviews in markdown: https://appshunter.io/ios/app/hvac-3d-design-learning-studio/id6766627551/reviews.md ## What is HVAC 3D Design Learning Studio? 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. ## Version history (last 3 releases) ### 3.0 — 2026-06-13 Version 3.0 — Six Major New Tools Duct Sizing Calculator — SMACNA equal-friction and velocity method sizing. Enter CFM, get round or rectangular duct dimensions with live velocity and friction rate checks. ASHRAE 62.1 Ventilation Calculator — Full multi-zone Ventilation Rate Procedure (VRP). Add zones by space type, enter area and occupancy, instantly calculate required outdoor air (Vot) per ASHRAE 62.1. Hydronic Pipe Sizing Calculator — Darcy-Weisbach pipe sizing for chilled water, hot water, and condenser water. Input GPM or calculate from tons/MBH — get recommended pipe size with ASHRAE velocity and friction limits. Sequence of Operations Library — Six complete BAS control sequences with step-by-step logic: Economizer, Demand-Controlled Ventilation, Supply Air Temperature Reset, Morning Warm-Up, Chiller Staging, and VAV Box Control — all per ASHRAE Guideline 36. A2L Refrigerant Safety Guide — Complete 2025 installation reference for R-454B, R-32, and other A2L refrigerants. Covers detector placement and setpoints, machinery room ventilation, charge limits, ignition source control, and EPA 608 compliance per ASHRAE 15-2022. PDF Export — Export the Equipment Schedule, ASHRAE 180 Inspection Checklist, and Calc Sheets as formatted PDF documents, shareable via AirDrop, email, or Files. Revised the description for full functionality of the app. ### 2.1 — 2026-05-18 Version 2.0 adds three major new professional tools: Psychrometric Chart -- Interactive ASHRAE psychrometric chart with real-time state-point calculation (enthalpy, dew point, wet-bulb, humidity ratio, specific volume) in SI and IP units. Includes ASHRAE 55 comfort zone and pinch-to-zoom. HVAC System Design Wizard -- 5-step guided tool that recommends the right HVAC system based on building type, floor area, ASHRAE climate zone (1-8), and design priority. Returns system type, SEER2/EER ratings, cost range, refrigerant, and applicable ASHRAE/ACCA standards. Refrigerant Phase-Out Guide -- Complete 2025 EPA AIM Act compliance reference: phasedown timeline, refrigerant comparison table (R-22, R-410A, R-454B, R-32, R-134a, R-1234ze), contractor decision guide, and A2L safety requirements per IBC/IMC 2024. Also in 2.0: Pinch-to-zoom on Floor Plan and Riser Diagrams, gallery expanded to 49 diagrams, UILaunchScreen update (iOS 14+), arm64 device capability. ### 1.0 — 2026-05-05 No release notes. ## More apps by Yuhsiu Lai - [Availability and Reliability](https://appshunter.io/ios/app/availability-and-reliability/id435033141) - [Battery Capacity Calculator](https://appshunter.io/ios/app/battery-capacity-calculator/id445176473) - [48VDC Power System](https://appshunter.io/ios/app/48vdc-power-system/id449477913) - [NEC Electrical Code Tools](https://appshunter.io/ios/app/nec-electrical-code-tools/id469334093) - [Engineer's Toolset](https://appshunter.io/ios/app/engineers-toolset/id478486737) - [Battery Current Simulator](https://appshunter.io/ios/app/battery-current-simulator/id488430945) All apps by Yuhsiu Lai: https://appshunter.io/developer/433114647 ## Related topics [ashrae hvac pt chart](https://appshunter.io/ios/topics/ashrae-hvac-pt-chart) · [hvac ashrae 62.1](https://appshunter.io/ios/topics/hvac-ashrae-62-1) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-31.*