ManualJ Lite
HVAC Load Calculator
$4.99 · Designed for iPad. Not verified for macOS.
3-ton AC on an 1,800 sq ft Zone 4 house - oversized? Sensible plus latent BTU/h and tonnage by the Manual J simplified method, 7 IECC zones. $4.99 one-time, no login.
ManualJ Lite is a fast, offline HVAC load calculator based on the Manual J simplified method. Enter your building details and instantly get cooling and heating load estimates for proper equipment sizing.
WHAT IT CALCULATES:
Cooling Load:
- Sensible and latent cooling loads (BTU/h)
- Total cooling capacity required
- AC tonnage recommendation
- Load breakdown by component
Heating Load:
- Total heating BTU/h
- Heat loss through walls, windows, roof
- Infiltration losses
- Recommended furnace capacity
BUILDING INPUTS:
- 7 IECC climate zones (Zone 1 through Zone 7)
- Floor area in square feet
- Insulation quality (Poor, Average, Good, Excellent)
- Window type (Single, Double, Low-E Double, Triple)
- Number of stories and orientation
KEY FEATURES:
- Simplified Manual J calculation method
- Cooling and heating mode toggle
- Component-level load breakdown percentages
- Instant results as you adjust inputs
- Clean, easy-to-read results layout
- Works completely offline
- No account or login required
BUILT FOR HVAC TECHS:
Whether you are an HVAC technician, contractor, or homeowner planning a system upgrade, ManualJ Lite gives you quick load estimates for equipment sizing. Select your climate zone, enter building specs, and get BTU and tonnage results in seconds.
Covers all 7 IECC climate zones with appropriate design temperatures for accurate residential load calculations.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Added a More Pro Tools section to discover related field calculators.
The developer, Shanghai Sheyuan Network Technology Co., Ltd., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Shanghai Sheyuan Network Technology Co., Ltd.
- Size
- 1.2 MB
- Category
- Utilities
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Sheyuan Inc.
