Before carrying out any maintenance work, please ensure you are competent to carry out any commercial activities, and you have read all the product information regarding the appliance.
Before attempting any electrical fault finding ALWAYS carry out the preliminary electrical system checks as detailed in the Instructions for the British Gas Multimeter or other similar commercially available meter.
The preliminary electrical system checks are the FIRST electrical checks to be carried out during a fault finding procedure.
On completion of any service/fault finding task which has required the breaking and remaking of electrical connections the following checks MUST be repeated:
- Earth continuity
- Resistance to earth
Detailed instructions on the replacement of faulty components are contained in the 'servicing' section of the Installation & Servicing manual for the relevant product (available in electronic format in the downloads section of this website) and a hard copy is available with the boiler or upon request.
Before carrying out fault finding ensure that all external controls are calling for heat. There should be a 230V 0-10V available at the control box connection.
The boiler control module has replaceable fuses protecting the 230V and 24V circuits. A common reason for the 230V fuse to blow would be if the pump connected to the boiler was drawing more than 1 amp.
If the 230 V fuse has blown, the display will be blank. Check for short circuits and pump loads before replacing the fuse.