Biasi E05 Fault Code (BASICA COND)

Safety disclaimer

Fault code summary

Manufacturer

Biasi

Fault code

E05

Fault type

Fan, Flue, Electrical

Severity

high

Reset

No unrestricted user reset is confirmed for this fan fault; arrange qualified diagnosis if it recurs.

Applicable models

BASICA COND 24C, BASICA COND 28C, BASICA COND 32C

Quick answer

Fan-control anomaly.

What does this fault code mean?

Fan-control anomaly.

Common causes

• Fan-control anomaly

Symptoms

• E05 shown on the LCD

What can the homeowner safely check?

• Check only that the boiler has power and that external controls are on; do not inspect or test the fan.

Boiler reset information

No unrestricted user reset is confirmed for this fan fault; arrange qualified diagnosis if it recurs.

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 investigate fan operation, feedback, wiring and the flue system.

Applicable boiler models

• BASICA COND 24C
• BASICA COND 28C
• BASICA COND 32C

Related fault codes

• E01 — BASICA COND

  Safety lockout due to failed ignition.

  Read fault code
• E02 — BASICA COND

  Lockout due to the safety thermostat.

  Read fault code
• E03 — BASICA COND

  EEPROM error.

  Read fault code
• E04 — BASICA COND

  Pump circulation failure or insufficient system pressure.

  Read fault code
• E06 — BASICA COND

  Heating NTC probe failure.

  Read fault code
• E07 — BASICA COND

  DHW NTC probe failure.

  Read fault code
• E08 — BASICA COND

  External NTC probe failure.

  Read fault code
• E09 — BASICA COND

  Flue-gas NTC probe interruption.

  Read fault code

Manufacturer documentation

SIGNAL DISPLAYED BY THE LCD: | E05+ | Fan control anomaly |

Last verified

2026-09-12

Frequently asked questions