Free HVAC Software in 2026: The Complete Guide for Small Contractors

Krib Team · 2026-02-23

An honest breakdown of every free HVAC tool available — from business management software to load calculators and refrigerant apps.

What are the best free HVAC software options for small businesses?

For business management, Krib offers one of the broadest free feature sets among HVAC-specific tools — scheduling, invoicing, quoting, customer management, and payment collection with no monthly fee (standard payment processing fees of 2.9% + $0.30 + 0.1% platform fee apply on collected payments). For engineering tools, CoolCalc provides free ACCA-approved Manual J calculations.

Can you recommend free HVAC software with scheduling and invoicing features?

Krib includes both scheduling and invoicing at no cost, plus quoting, customer management, and payment collection. DoTimely also offers a free tier with scheduling and invoicing.

Is there free HVAC load calculation software?

Yes. CoolCalc offers free ACCA-approved Manual J load calculations. LoadCalc.net offers free block load calculations. ServiceTitan provides a simplified free BTU calculator.

Is free HVAC software really free or is there a catch?

It depends on the model. Genuinely free tools like Krib charge no monthly fee — the only cost is standard payment processing (2.9% + $0.30 + 0.1% platform fee) on collected payments. Free trial tools give 7–14 days then require payment. Freemium tools offer limited free tiers with key features locked behind paid plans.

What free tools do HVAC contractors use to run their business?

Many piece together Wave for invoicing, Google Calendar for scheduling, and Venmo for payments. Purpose-built free options like Krib combine all of these into one platform at no cost.

Free contractor software by trade