Biasi E26 Fault Code (BASICA COND)

Safety disclaimer

Fault code summary

Manufacturer

Biasi

Fault code

E26

Fault type

Gas valve, Gas supply, Safety lockout

Severity

high

Reset

No unrestricted user reset is confirmed; gas-valve faults require qualified diagnosis.

Applicable models

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

Quick answer

Gas-valve fault.

What does this fault code mean?

Gas-valve fault.

Common causes

• Gas-valve fault

Symptoms

• E26 shown on the LCD

What can the homeowner safely check?

• Record the code and do not adjust, test or replace the gas valve.

Boiler reset information

No unrestricted user reset is confirmed; gas-valve faults require qualified diagnosis.

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 Gas Safe engineer should investigate gas-valve operation, wiring, supply and control signals.

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
• E05 — BASICA COND

  Fan-control anomaly.

  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

Manufacturer documentation

SIGNAL DISPLAYED BY THE LCD: | E26+ | Gas valve fault |

Last verified

2026-09-12

Frequently asked questions