Verified boiler fault code

Warmflow E02 Fault Code (Agentis Boilers (B-Series, I-Series and E-Series))

High limit.

Safety disclaimer

Boiler repair help from Aza & Sons Services

Fault code summary

Manufacturer: Warmflow
Fault code: E02
Fault type: Overheating, Safety lockout, Circulation
Severity: high
Reset: The manual directs the user to a service engineer for E02; do not repeatedly reset a high-limit fault.
Applicable models: B21, B26, B33, I21, I26, I33, I44, I21PRO, I26PRO, I33PRO, I44PRO, I21P/PRO, I26P/PRO, I33P/PRO, I44P, I21S/PRO, I26S/PRO, I33S/PRO, I21C/PRO, I26C/PRO, I33C/PRO, E21, E26, E33, E44, E21PRO, E26PRO, E33PRO, E44PRO, E21P/PRO, E26P/PRO, E33P/PRO, E44P, E21S/PRO, E26S/PRO, E33S/PRO, E21C/PRO, E26C/PRO, E33C/PRO

Quick answer

High limit.

What does this fault code mean?

High limit.

Common causes

Air lock in boiler
Displaced NTC temperature sensor
Circulation problem

Symptoms

E02 displayed on the LCD
High-limit fault

What can the homeowner safely check?

Allow the appliance to cool and record the code; do not remove covers or reset internal safety devices.

Boiler reset information

The manual directs the user to a service engineer for E02; do not repeatedly reset a high-limit fault.

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 air in the boiler, the NTC sensor and circulation.

Applicable boiler models

Related fault codes

Manufacturer documentation

Warmflow Agentis Boiler Manual 6572 G

Last verified

2026-09-12

Frequently asked questions

What does Warmflow E02 mean?

High limit.

Can I reset a Warmflow E02 fault?

The manual directs the user to a service engineer for E02; do not repeatedly reset a high-limit fault.