UK Appliance Error Codes

Error code

Ideal Boiler Fault Code F6

A boiler sensor is giving an invalid reading The most likely cause is faulty sensor. Check first: use only the standard reset process if it is intended for homeowners.

Last updated: 2 April 2026Boiler faults need a cautious approach

Quick answer

F6: what does it mean and how to fix

medium severity

What does it mean?

A boiler sensor is giving an invalid reading

How to fix first

Consult the manual for any user guidance specific to this fault.

Why is this happening?

Faulty sensor

When should I call an engineer?

If the code remains after one standard reset, a qualified heating engineer should inspect the boiler.

What does this error code mean?

Ideal boiler fault code F6 usually means the boiler is receiving an unexpected reading from one of its temperature or system sensors.

In practice, F6 is commonly linked to Faulty sensor, Wiring issue, or Control board not interpreting the sensor correctly.

Start with this safe check: Consult the manual for any user guidance specific to this fault. If the code returns, the fault worsens, or the appliance does not behave normally, if the code remains after one standard reset, a qualified heating engineer should inspect the boiler.

Why is this happening?

  1. Faulty sensor
  2. Wiring issue
  3. Control board not interpreting the sensor correctly

How to fix this safely

  1. Consult the manual for any user guidance specific to this fault.
  2. Use only the standard reset process if it is intended for homeowners.
  3. Stop if the code reappears immediately.

Reset steps

  1. Carry out one standard user reset if the manual allows it.
  2. Arrange professional diagnosis if the sensor fault remains active.

When to call an engineer

If the code remains after one standard reset, a qualified heating engineer should inspect the boiler.

Safety warning

Do not remove the boiler casing or handle internal wiring or sensor components yourself.

Useful hub links

Related sensor fault codes

Relevant guide

Frequently asked questions

Can I keep resetting a Ideal boiler with F6?+

No. If F6 returns after one standard user reset, stop there and arrange a qualified engineer if the manual gives no safe next step.

Is F6 something I can repair myself?+

Boiler faults should be treated cautiously. Stay within the user checks in the manual, and leave gas, combustion, and internal boiler repairs to a qualified professional.