Mira Advance ATL Installation & User Manual page 41

4. Relay Board – Renewal
4.1. To renew the relay board assembly:
4.1.1. Remove all the plug-in multi connectors.
4.1.2. Remove the terminal block cover retaining screws and the cover.
4.1.3. Remove the wires to the element assembly.
4.1.4. Remove the two earth fly leads.
4.1.5. Remove the relay board retaining screws.
4.1.6. Renew the relay board.
4.1.7. Refit in reverse order.
5. Transformer – Renewal
5.1. To renew the transformer:
5.1.1. Isolate the electrical power.
5.1.2. Remove the terminal block cover.
5.1.3. Remove the two upper relay board retaining screws.
5.1.4. Unplug the transformer connector lead.
5.1.5. Remove the transformer retaining screw.
5.1.6. Unplug the following:
- Solenoid plug PL8
- Flow sensor plug PL4
- Outlet sensor plug PL3.
5.1.7. Remove the two earth fly leads device leads fitted to the relay board.
5.1.8. Remove the element connections and remove the relay board.
5.1.9. Remove the transformer and unclip the thermal switch on top of the
heater element. Remove the thermal switch.
5.1.10. Refit in reverse order. Make sure that:
- the transformer wires do not become trapped underneath
- the transformer or busbar when refitting.
- the thermal switch makes good contact with the tank top.
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