About
HVAC Load is an HVAC load calculator for contractors, installers and estimators who size systems for houses. Enter the floor area, the ZIP code and the year the house was built. You get the heating and cooling load in BTU/h and the size in tons. The year built fills in insulation, windows, air leakage and ducts, so you have a first number before any other question. Then go as deep as the job needs. The load breakdown shows where the heat comes from: walls, windows, sun on the glass, air leaks and ducts. A what-if list shows how many BTU/h each fix would save. Add rooms to get the heat, the cool, the airflow and a round duct size for each one, or switch to ductless heads for a mini split. The equipment check tells you if the unit you plan to quote fits the load. For a heat pump it shows the balance point and the backup heat in kW. A fuel use check compares the result with last winter's fuel. When you are done, make a two page PDF report with your logo, your company details and your client. The web app is free in any browser, with no account and no limit on jobs. The math runs on your device, so after the first visit it works with no signal in an attic or a crawl space. Jobs stay on your device. Climate data covers about 1,200 US weather stations. iPhone and Android apps are coming soon. Results are estimates in the style of ACCA Manual J. They do not replace a certified room by room design. HVAC Load is not affiliated with ACCA.