E.C.A.•Gas boiler

E.C.A. Gas boiler E03: Overtemperature warning

The E.C.A. manufacturer reference describes E03 as overtemperature warning. The code alone does not establish which component, if any, requires repair.

Model-specific sourceOfficial manufacturer reference
ERROR CODEE03E.C.A. · Gas boiler

Model compatibility has not been independently verified

Earlier archive data contained suggested model or series names. Without a clear model/code table in a manufacturer manual, these names are no longer displayed as verified matches.

This is general brand/device guidance; check the model label and official manual.

Open manufacturer source

What does this code mean?

The E.C.A. manufacturer reference describes E03 as overtemperature warning. The code alone does not establish which component, if any, requires repair.

Manufacturer evidence

This definition is based on the manufacturer support/manual for Proteus Premix 14–45 kW HM/HCH/HST. Confirm the exact model before acting.

Read official manufacturer reference

What can you try safely?

Only follow steps approved for your specific model; stop if the fault indicates an unsafe condition.

  1. 01

    Confirm model and error

    Photograph the exact display code E03 and read the complete model label. This definition is based on the manufacturer support/manual for Proteus Premix 14–45 kW HM/HCH/HST. Confirm the exact model before acting.

    How to interpret the result: The precise model is essential.

  2. 02

    Safe user check 1

    Allow the appliance to cool. Verify accessible radiator valves and system pressure without opening the cabinet. Do not repeatedly reset overheating protection.

    How to interpret the result: Observe the result without opening internal assemblies.

  3. 03

    Safe user check 2

    After any permitted user check, observe whether the error recurs during normal operation; do not repeat lockout resets or open the unit.

    How to interpret the result: Observe the result without opening internal assemblies.

  4. 04

    Safe user check 3

    Record when the issue began, any visible pressure or leak, and checks completed for a qualified technician. Ask which measurement supports any proposed repair.

    How to interpret the result: Observe the result without opening internal assemblies.

How is the fault resolved?

User-accessible checks

  1. Allow the appliance to cool. Verify accessible radiator valves and system pressure without opening the cabinet. Do not repeatedly reset overheating protection.
  2. After any permitted user check, observe whether the error recurs during normal operation; do not repeat lockout resets or open the unit.
  3. Record when the issue began, any visible pressure or leak, and checks completed for a qualified technician. Ask which measurement supports any proposed repair.

Professional diagnosis and repair

A technician tests circulation, safety limits and temperature sensors after the unit cools.

How to verify success: The error should no longer recur during normal operation. If it does, stop repeated attempts and request model-specific help.

Important: Never open gas-valve, combustion, flue or live-electrical assemblies. If you smell gas, do not operate electrical switches or appliance controls or create sparks. Leave the area safely and contact the local gas emergency service from outside. Unauthorized repairs may affect warranty coverage, depending on the applicable warranty terms and law.

Why can this happen?

The E.C.A. manufacturer reference describes E03 as overtemperature warning. The code alone does not establish which component, if any, requires repair.

  • Manufacturer identifies a system condition, not necessarily a failed part.
  • Model and operating circumstances affect the cause and proper repair.

Is this code valid for your appliance?

This definition is based on the manufacturer support/manual for Proteus Premix 14–45 kW HM/HCH/HST. Confirm the exact model before acting.

Search other error codes