Ideal Logic System IE fault L7

Less than 5°C rise on 3 successive occasions

Gas boiler

What it means

Flow/return temperature rise of less than 5°C detected on three successive attempts. Burner will be switched off for 2 minutes between attempts. Function inactive if temperature is above 40°C.

Likely causes

  1. Thermistors not clipped onto pipes correctly
  2. Poor thermal contact between thermistor and pipe

Where to start

  1. Check thermistors are clipped onto pipes
  2. Unclip return thermistor from return pipe and withdraw from boiler.
  3. Disconnect electrical lead from thermistor.

The full answer, free

  • The readings and component tests from the manual
  • How to put it right, step by step
  • The manual page for this fault (page 54), right under the answer

Safety: Isolate gas and power before you open the case. If you have been into the gas side, do a tightness test, and a combustion and flue check before you hand back. Gas Safe (UK) or RGI (Ireland) work only.

From the Ideal manual for the Logic System IE. Check the model on the data plate before you order parts.

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