HVAC Calculator: BTU & AC Loadv1.1

What changed

• New featureAdded Duct Size Calculator using equal-friction method
• New featureAdded Heat Load Calculator for room-by-room cooling estimates
• UXImplemented data transfer between exhaust fan and duct sizer tools
• UXConsolidated all calculators onto a single screen for easier access
• New featureExpanded saved projects feature to include new calculation types
• LocalizationTranslated new calculators into 20 supported languages

Original release notes

Two new calculators — and a faster way to reach all of them.

DUCT SIZE CALCULATOR
Size round and rectangular duct by the equal-friction method. Enter
airflow in CFM or m³/h, choose a friction rate, and get the exact
diameter, the nearest standard duct size, and an air velocity check that
warns you before a run turns noisy. Rectangular ducts show width × height
plus the equivalent round diameter.

HEAT LOAD CALCULATOR
Estimate the cooling load room by room for a whole property. Add each
room with its dimensions, sun exposure, occupants and kitchen, then read
the total in BTU/h, tons and kW with a per-room breakdown — a quick first
pass before a full Manual J.

FAN TO DUCT IN ONE TAP
Work out exhaust airflow, then send that CFM straight into the duct sizer
without typing it again.

NEW CALCULATORS SCREEN
Air conditioning, exhaust fan, duct size and heat load now sit together
on one screen instead of separate tabs.

ALSO IN THIS UPDATE
• Saved projects now hold duct and heat load calculations too
• Both new calculators translated into all 20 supported languages

Every calculation still runs offline, in metric or imperial.