TechDiagnoseTechDiagnose
Field diagnostics

The AI troubleshooting partner built for HVAC techs.

Stop guessing at the condenser. Pick the equipment, describe the symptoms, and TechDiagnose walks you through a ranked, step-by-step diagnosis with the exact tests to run and the safety warnings that matter.

Free to tryNo credit card requiredWorks on phone, tablet, and desktop
Ranked causes
Field tests
Safety warnings
Photo analysis
Saved history
Offline mode

What TechDiagnose does

Everything you need to narrow a callback fast.

From the first symptom to the final cause, the app guides you like a senior tech standing next to you — asking one useful question at a time, showing you what to check, and keeping every step on record.

Start diagnosing with HVAC tech-tested AI

Built on real field fault trees. The AI asks the same questions a senior tech would ask — one targeted step at a time.

Ranked causes and exact tests

Get the most likely failures in order, each with the specific measurements, pressures, voltages, and resistance values to confirm them.

Safety warnings up front

Refrigerant, electrical, combustion, and oil-burner hazards are flagged before you touch the unit, not buried in the notes.

Show the AI what you're seeing

Snap photos of error codes, control boards, wiring, or oil burner cad cells. Multimodal AI reads the image and folds it into the diagnosis.

Complete diagnostic history

Every question, answer, photo, and final cause is saved in a step-by-step timeline. Perfect for callbacks, warranty claims, and training.

Works offline, syncs later

No signal in the attic or basement? No problem. Start the diagnosis, cache the history, and sync when you're back on the network.

Equipment supported

Residential and light commercial systems, including oil-fired equipment.

Split systemsHeat pumpsGas furnacesOil furnacesOil boilersAir handlersPackage units

Brand-specific intelligence

Select the manufacturer and model to get fault-code meanings, common failure patterns, and proprietary control behavior.

CarrierTraneLennoxDaikinRheemGoodmanYorkBryantBeckettRielloThermo Pride+ more

How it works

Four steps from symptom to solution.

01

Choose the unit

Pick equipment type, brand, and model so the AI knows the control logic it's working with.

02

Describe symptoms

Enter what you see and hear — or snap a photo of the board, nameplate, or error code.

03

Answer guided questions

The AI narrows the fault tree one binary question at a time, like a senior tech on the phone.

04

Get ranked causes

Receive likely failures, the tests to confirm them, and the safety warnings that apply.

Pricing

Start free, then $12.99 a month.

7-day free trial, no credit card required. Team plans are priced per technician with shared company history.

Pro — Monthly

$12.99/mo

For the solo tech. Billed monthly, cancel anytime.

Start free trial

Pro — Yearly

$129/yr

Everything in Pro, two months free when you pay yearly.

Start free trial

Team — Monthly

$10.99per tech/mo

Per technician, billed monthly. One account for the whole shop.

Start free trial

Team — Yearly

$109per tech/yr

Per technician, billed yearly. Best value for established shops.

Start free trial
See full plan comparison

Ready to stop troubleshooting blind?

Join HVAC technicians who use TechDiagnose to get to the right call faster, prove the repair, and keep a record of every callback.

Start diagnosing free