Worcester Bosch Control Box With Code Plug 8737604615

The Worcester Bosch 8737604615 is a control box assembly supplied with code plug 25135 (NG). It sits at the heart of the boiler's electronic control circuit, housing the board and connections that manage ignition sequencing, temperature regulation and communication with the user controls on the appliance front panel.

This is a manufacturer-supplied component for the Worcester Bosch Greenstar combi range and is listed against the Greenstar 2000 Combi and Greenstar GR2300iW 25 C NG platforms.

• The boiler is completely unresponsive when the power supply and external controls are confirmed working
• The front panel display or indicator LEDs are dead, blank or flickering erratically
• Fault codes relating to the control board appear and cannot be cleared by a reset
• The boiler fires intermittently or locks out with no obvious mechanical or water-side cause
• Buttons on the control fascia stop registering inputs, or the appliance ignores a demand for heat and hot water

• Check the GC number on the appliance data badge against the compatibility list below; the GC number identifies the exact model variant
• The control box is supplied with code plug 25135 (NG), which sets the appliance gas type and configuration — confirm this matches the boiler being worked on
• Earlier builds may carry part number 8737603352; compare the number on the existing control box before ordering a replacement
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.