BoilerFaultCodes.com

Worcester Bosch R30 35 And 40 HE Plus Fault Codes

System Natural GasLPG 30-40 kW 2003-2007 Discontinued
GC Numbers: 41-311-7341-311-7441-311-75

Replaced by: Greenstar 30CDi System

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Most common fault codes

A1
Your boiler is trying to circulate water but cannot find enough pressure or flow to do so safely, often because the system is low on water.
May be DIY safe · £0-120
A8
Your boiler has lost its connection to the external temperature controller or room thermostat, meaning it cannot receive instructions on when to turn the heating on.
May be DIY safe · £90-250
AC
Your boiler's main control computer has lost contact with the front display panel, meaning the two parts can no longer 'talk' to each other to operate the system.
Gas Safe engineer required · £150-£450

All 24 fault codes

Code Severity Plain English
−II− Low Your boiler is currently running a 15-minute cleaning and safety cycle to fill up its internal drainage system, which is a normal process after a power cut or reset.
0.0 Low Your boiler is in service mode and is simply displaying the last fault code that occurred rather than indicating a current active breakdown.
A1 High Your boiler is trying to circulate water but cannot find enough pressure or flow to do so safely, often because the system is low on water.
A7 Medium Your boiler is having trouble measuring the temperature of your hot water, which means your taps might run cold or the water temperature could be inconsistent.
A8 High Your boiler has lost its connection to the external temperature controller or room thermostat, meaning it cannot receive instructions on when to turn the heating on.
AC High Your boiler's main control computer has lost contact with the front display panel, meaning the two parts can no longer 'talk' to each other to operate the system.
b1 High Your boiler is not running because its essential internal programming 'code plug' or 'key' is missing or has lost connection with the main control board.
C1 High Your boiler’s air fan is not spinning fast enough to safely clear out exhaust gases, so the system has shut down as a precaution.
C4 High Your boiler's internal fan is staying on when it should be turning off, which prevents the boiler from starting its normal heating cycle.
C6 High Your boiler has stopped working because its internal fan is spinning faster than it should, which has caused the system to shut down for safety.
CC Low Your boiler has lost its connection to the outside temperature sensor, which helps it run efficiently.
E2 High Your boiler has detected a fault with the internal thermometer that monitors water temperature, causing the system to shut down for safety.
E9 High Your boiler has shut down because it has detected internal temperatures that are dangerously high, triggering a safety cut-out to prevent damage.
EA High Your boiler has tried to ignite but cannot detect a flame, so it has shut down for safety.
F0 High Your boiler's internal computer has encountered a software or communication glitch that prevents it from running.
F7 High Your boiler is failing to detect the flame it has lit, causing it to shut down for safety.
FA High Your boiler is still detecting a flame or heat signal even after it has been told to turn off, which is a safety conflict.
FC High Your boiler's control panel and its internal computer are not communicating properly, so the display is unable to show information.
Fd Low Your boiler is showing this code because the reset button was held down for too long or pressed accidentally while the boiler was working normally.
P1 Low Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
P1, P2, P3, P1... Low Your boiler is simply starting up and checking its internal systems; this is a normal part of the power-on process.
P2 Low Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
P3 Low Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
P4 Low Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.

Status & diagnostic codes

These codes indicate your boiler's operating state or a diagnostic reading — not necessarily a fault. Status codes (S.) mean normal operation; diagnostic codes (D.) are informational readings used by engineers.

Code Type Description
d3 Diagnostic Your boiler has lost its connection to the external safety control system or its internal link plug, causing the unit to stop running for safety.

Worcester Bosch R30 35 And 40 HE Plus is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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