Intergas · HRE, ECO RF & Rapid with iC3 PCB

5Poor flame signal

This code applies to Combi Compact HRE 24/18, Combi Compact HRE 28/24, Combi Compact HRE 36/30, Combi Compact HRE 36/40, ECO RF, Rapid 25, Rapid 32. Fault codes narrow down the likely problem, but they do not replace a model-specific diagnosis.

What you can safely check

Check whether another gas appliance works and whether a prepayment meter has credit.
In freezing weather, visually check an accessible external condensate pipe for ice and follow the manufacturer's thawing guidance if applicable.
Reset once only if the user manual permits it. If the code returns, arrange an engineer.

How an engineer may fix it

Test the gas supply and inlet pressure, ignition and ionisation components, condensate route, flue, gas valve and combustion settings; repair or replace the failed component.

Manufacturer source: Intergas — HRE, ECO RF & Rapid Parameters and Fault Codes (V10). Checked 15 August 2026. The appliance manual and an engineer’s on-site diagnosis take precedence. Never remove the boiler case yourself.