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Free + Pro

Air Conditioning and Heat Pump Fault Finding App

The manufacturer's own fault chart, where we hold one. Readings on a P-h chart with a verdict. It never tells you to change a board you haven't measured.

Try it free
A diagnosis on a phone ranking the likely faults, with low charge first and a note to weigh the refrigerant before deciding.

What it does

  • The manufacturer's own fault chart for your model, where we hold one, one question at a time.
  • Other codes give you the meaning and the causes, with the manual they came from.
  • Readings on a P-h chart with a verdict: within tolerance, or the likely causes ranked.
  • It never tells you to change a board you haven't measured.

Fault codes by make

Mitsubishi EcodanGrant AeronaVaillant aroTHERMViessmann VitocalLG Therma VSamsung EHSPanasonic AquareaNIBEBosch CompressDaikinGreeMideaKaisaiHaierFujitsu WaterstageFujitsu GeneralToshibaHitachiWorcester Greenstore
A pressure-enthalpy chart of an air conditioner's refrigerant cycle, with the measured figures and a ranked list of likely faults.

Which plan

Free + Pro

Free, with no account: the fault code wizard, with the manufacturer's chart where we hold one, the fault-code pages, the P-h readings verdict and the demo.

Free once you sign up: one guided investigation.

Pro: guided investigation from the symptom as often as you like, your readings saved to the job and the report, and Reference.

Pro is £9.99 a month, or £99 a year, on the launch rate. New accounts get the first month free, with no card needed.

Pro is bought in the app. The App Store shows the price before you confirm.

Questions

Do I need an account?

Not for the fault charts, the fault-code pages or the P-h verdict. They work with no account. Sign up and you get one guided investigation free.

Is it the manufacturer's own fault chart?

Yes, where we hold one for that model and code, and it takes you through it one question at a time. For other codes you get what the code means and its causes, with the manual it came from.

What does the P-h chart tell me?

Put your pressures and temperatures in and it plots the cycle and gives a verdict: within tolerance, or the likely causes ranked, with the reason for each.

Will it tell me to change the board?

Not until you've measured it. Every route to a board verdict goes through a measurement. Where the manual gives no check, it calls the board the remaining suspect and names the manual section it checked.

What does Pro add?

Guided investigation from the symptom as often as you like, your readings saved to the job and printed on the report, and Reference.