HVAC Load Calculator Manual J

New: LiDAR room scanning. Walk each room and your iPhone measures floor area, ceilings, and windows for you — then prints a room-by-room chapter in your PDF report.

The Manual J HVAC Load Calculator is the one HVAC contractors actually want to use.

Stop overpaying for clunky, over-engineered calculators designed for engineers. HVAC Load Calculator brings professional Manual J calculations to your iPhone or iPad — clean, modern, offline-ready, and built for the field.

BUILT FOR HVAC PROFESSIONALS Designed from scratch for techs in the field: large buttons you can tap with gloves on, fast calculations in the basement, and professional reports that win homeowner trust.

THREE LEVELS OF ACCURACY

Simple Mode – 8 inputs Regional ZIP-code benchmarks and square-footage multipliers. Get an estimate in under 60 seconds with zero measurements. Perfect for quick quotes and initial sales conversations.

Moderate Mode – Standard Accuracy (Whole-House Block Load) – 15 inputs Component-level factors: insulation quality, window types, foundation — with a conservative safety buffer. The sweet spot for standard replacement jobs.

Pro Mode – Professional Grade (Detailed Whole-House Block Load) – 16 inputs + pro overrides Full MJ8 physics: altitude-adjusted density, solar load factors, CLTD daily-range lag, and separated duct analysis. Maximizes equipment life and comfort — often right-sizing by 1+ ton. Best for new construction, high-performance builds, and detailed equipment sizing.

MEASURE ROOMS WITH LiDAR — NEW On LiDAR-equipped iPhone and iPad Pro models (iOS 16+), walk each room and the app measures it for you — floor area, ceiling heights, windows, and exterior walls flow straight into your load calculation. Review each room, adjust with a tap, apply. Your PDF gains a Room Measurements chapter with a sketch of every scanned room.

NOW AVAILABLE WORLDWIDE US Mode – ZIP code lookup backed by a climate database covering nearly 28,000 ZIP codes International Mode – Enter your city, country, and local design temperatures directly — no ZIP code required. Choose your climate zone and moisture regime, and the calculator handles the rest. Metric Units – Toggle between Imperial and SI (kW, m², m³/h) throughout the app and PDF reports

WORKS IN THE FIELD Offline-First – No signal in the basement? No problem. Everything runs locally on your device. Auto-Save Projects – Every calculation saves automatically. Never lose your work. iCloud Sync – Start a job on your iPhone, finish it on your iPad. Projects sync automatically across your devices. Professional PDF Reports – Generate and share detailed load reports from your phone or tablet. Add client name, site address, and job number — every report is stamped with a revision number and date, so everyone knows it's the latest version. Site Photo Documentation – Capture tagged photos, label by location and component, add notes, and include a professional photo appendix in your reports. iPad & Tablet Support – Optimized layouts give you more room to work on-site or back at the office.

THE MATH YOU TRUST Calculations follow ACCA Manual J 8th Edition methodology: – Cooling BTU/hr (sensible and latent loads) – Heating BTU/hr – Recommended tonnage (rounded to 0.5 tons) – Recommended furnace size (rounded to 5,000 BTU) – Manual S-based equipment sizing guidance – Kitchen/appliance heat gain per MJ8 Table 4 If a result looks unusual for the home's size, the app flags it before the report goes out.

WHY CONTRACTORS CHOOSE US – Modern, intuitive interface that makes sense the first time you use it – Dark mode and system theme support – Fast performance, even on older devices – Privacy-first: your data stays on your device and your own private iCloud — never our servers – Free to download — try it on your first calculations before subscribing

PERFECT FOR – HVAC contractors, installers, and service techs – Sales teams quoting new systems – Independent contractors building their business – Home inspectors documenting HVAC systems

No account. No setup. Just open the app and get to work.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/