HVAC Load Calc: Manual J

HVAC Load Calc: Manual J

Heating & cooling calculator

0 ratings
Free
In-App Purchases

Rating summary

Details

  • Released
  • Updated
  • July 15, 2026
  • August 25, 2026
HVAC Load Calc: Manual J screenshot #1 for iPhone
HVAC Load Calc: Manual J screenshot #2 for iPhone
HVAC Load Calc: Manual J screenshot #3 for iPhone
HVAC Load Calc: Manual J screenshot #4 for iPhone
HVAC Load Calc: Manual J screenshot #5 for iPhone
iphone
ipad
🖼️Get Icon
Icons↘︎

About

Right-size any residential system in seconds. HVAC Load Calc runs a whole-house block load (the Manual J method) from a few envelope inputs. Every subscription starts with a free trial. After the trial, HVAC Load Calc requires a subscription, and everything described below is a subscriber-only feature. ENTER THE HOUSE - Floor area, ceiling height, and stories - Climate from the site ZIP code: it picks the nearest weather station, anywhere in the US. Search by town instead, or enter your own design temperatures. - Insulation presets for walls, ceiling, and floor (or your own U-values) - Window area and glazing type, air tightness, and occupants GET THE LOAD - Design HEATING load (BTU/h) - Design COOLING load, split into SENSIBLE and LATENT (BTU/h) - Recommended equipment TONNAGE, with a sanity check that flags oversizing KEEP THE JOB - Save a calculation under the job name and reopen it later with every input intact - The list shows each job's loads and tonnage, so you can find one without opening it - Everything stays on the device. There is no account to create. HAND OVER A REPORT - A one-page PDF: design loads, equipment size, and every input behind them - Look at the page before you send it, then share it like any other file ON IPAD - The form and the report sit side by side and update as you work WHERE THE NUMBERS COME FROM - Textbook ASHRAE heat transfer: envelope conduction, infiltration, solar and internal gains. This is the same basis as the ACCA Manual J block load. - Design temperatures from the ASHRAE tables, and from fifteen years of hourly NOAA records everywhere else. - Every assumption is on screen and you can change it. Cancel anytime in Settings. Engineering reference only. This is a whole-house block load, not a substitute for a certified room-by-room Manual J or professional engineering judgment. Terms: https://manualj.vovaluka.com/terms Privacy: https://manualj.vovaluka.com/privacy
Show more

What's New in HVAC Load Calc

1.1.1

August 25, 2026

Design temperatures now cover the whole country. Enter the site ZIP code and the app picks the nearest weather station, anywhere in the US. You can see which one it chose and change it, search by town instead, or enter your own design temperatures. The subscription screen now lists what the subscription includes: saved jobs and the one-page PDF report, as well as the load. You can see what you are getting before the trial starts.

More

Subscription plans

HVAC Load Pro

Unlimited load calculations and pro features

$9.991 Year
7 Days trial
How to cancel HVAC Load Calc subscription ⁉️

Developer apps