Verified boiler fault code

Biasi E08 Fault Code (BASICA COND)

External NTC probe failure.

Safety disclaimer

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Fault code summary

Manufacturer
Biasi
Fault code
E08
Fault type
Temperature sensor, Central heating
Severity
medium
Reset
No specific user reset is confirmed; arrange qualified diagnosis if the code remains.
Applicable models
BASICA COND 24C, BASICA COND 28C, BASICA COND 32C

Quick answer

External NTC probe failure.

What does this fault code mean?

External NTC probe failure.

Common causes

  • External NTC probe failure

Symptoms

  • E08 shown on the LCD

What can the homeowner safely check?

  • Record the code and do not disconnect or test the probe.

Boiler reset information

No specific user reset is confirmed; arrange qualified diagnosis if the code remains.

When should I call an engineer?

Contact a suitably qualified heating engineer when the fault persists, the boiler locks out, or the manufacturer instructions do not resolve it. For gas appliance work in the UK, use a Gas Safe registered engineer.

Engineer diagnosis

  • A qualified engineer should assess the external NTC probe, wiring and control settings.

Applicable boiler models

Related fault codes

Manufacturer documentation

Biasi BASICA COND user manual and installation instructions

SIGNAL DISPLAYED BY THE LCD: | E08+ | External NTC probe failure |

Last verified

2026-09-12

Frequently asked questions

What does Biasi E08 mean?

External NTC probe failure.

Can I reset a Biasi E08 fault?

No specific user reset is confirmed; arrange qualified diagnosis if the code remains.