Intergas · HRE, ECO RF & Rapid with iC3 PCB

50Low voltage between live and earth

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 for a wider power cut or a tripped consumer-unit circuit without removing the boiler case.
Use a qualified electrician or Gas Safe engineer for further diagnosis.

How an engineer may fix it

Verify supply voltage, polarity, earthing, fuses, harnesses and appliance electronics; correct the electrical supply 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.