Tier 01 · Apprentice

Free for the first four years of your career.

Years 1-4 in the trades are when you build the muscle. The Apprentice tier gives you unlimited AI Sensei chat across HVAC, Plumbing, Electrical, and Welding — plus EPA 608 prep, A2L and R-454B training, NATE drilling, an equipment database, and a code library — at zero cost. Sign in with Google, pick a trade, start drilling.

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What's included (free)

AI Senseis (4 trades)

HVACR Sensei (live), Plumbing Sensei (live), Electrical Sensei (beta), Welding Sensei (Q3 2026). Domain-trained. Socratic-style. Unlimited chat. Tracks your progress.

Certification prep

EPA 608 (Type I, II, III, Universal), A2L refrigerant handling, R-454B field service, and NATE prep across multiple tracks. Unlimited drilling.

Diagnosis tools

Diagnose specific equipment by model number. Visual AI for nameplate reads, PT chart interpretation, and field diagnostics.

Equipment database

Searchable database of common residential and commercial HVAC equipment — Carrier, Trane, Lennox, York, Rheem, Daikin, Mitsubishi — plus plumbing fixtures, electrical panels, and welding machines.

Code library

Quick lookups against EPA 40 CFR (refrigerants), NEC (electrical), IMC (mechanical), UMC, and ASHRAE standards. Sensei surfaces relevant code citations contextually.

Mentor + community

Request a Journeyman mentor through the platform. Mentor can share their CRM customer base with you so you train on real-world tickets, not synthetic problems.

Who the Apprentice tier is for

Career-changers stepping into the trades from another career.
Veterans using GI Bill or transitioning post-service into a high-demand trade.
JATC apprentices looking for supplemental drilling between classroom hours.
Current journeymen upskilling for cross-trade certifications (NATE, A2L) or pivoting to a second trade.
High-school graduates entering the trades directly instead of college.

Why free for four years

The first four years in the trades are when retention is most fragile. National data shows up to 50% of new entrants leave the trade within five years. The cost of a paywall is a leaky funnel.

By making the Apprentice tier free, ATH lowers the activation cost to zero. Trainees who reach Journeyman tier ($499/mo, with apprentice management + jobs + CRM integrations) have already proven the model works. Pipeline economics, not gating.