How much does it cost to fix Worcester Bosch error code 52124?

Typical repair cost for the Worcester Bosch 52124 fault is £90-180 including labour.

52124 High

Worcester Bosch 52124 Fault Code

Q: What does the Worcester Bosch 52124 fault code mean?

Your boiler's internal temperature sensors have likely been plugged into the wrong sockets or have developed a wiring fault, meaning the system cannot accurately track how hot the water is.

The Worcester Bosch 52124 fault code means: your boiler's internal temperature sensors have likely been plugged into the wrong sockets or have developed a wiring fault, meaning the system cannot accurately track how hot the water is.. It appears on 1 Worcester Bosch model in our database.

Technical description: Temperature sensors (T1 and T2) reversed.

What causes the Worcester Bosch 52124 fault?

This fault occurs when the boiler's control board detects that the temperature readings from the flow and return pipes are swapped or illogical. The most common reason is that the internal sensors were plugged into the wrong ports during a recent repair, or a fault in the wiring harness is sending confusing signals to the main computer.

Typical repair cost £90-180 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Worcester Bosch models that show the 52124 fault code

Click a model for the full fault code list and model-specific repair notes.

Greenstar CDi Compact Repair: £90-180

Source

Worcester Bosch 52124 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026