Disconnecting a fixed appliance in a flood-damaged shop
A cafe has been flooded to 300 mm. The owner wants you to disconnect and later reconnect a fixed electric hot water unit and a hard-wired commercial dishwasher so the shop can be cleaned and reopened quickly. The switchboard is in the flooded area and shows water staining; the circuits are not labelled clearly. The hot water unit is on a dedicated circuit with a nearby isolator, but the dishwasher is wired directly into a junction box behind the cabinet. The owner says the power has been 'checked' by a friend who is an electrician, but there is no certificate or record. You hold the relevant disconnection and reconnection authorisation for fixed electrical equipment.
1. Can you disconnect both appliances now, and what conditions must be met first?
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Disconnection and reconnection of fixed electrical equipment is permitted only within the scope of your authorisation and only when the equipment and its supply are safe to work on. The flooded switchboard is the first problem. Water-stained switchgear in a flood zone must be assessed by a licensed electrician before it is relied on; a verbal 'checked' by a friend with no record is not evidence. Until the board is confirmed safe and the circuits identified, you should not be working on connected equipment.
Assuming the board is made safe, the hot water unit can be isolated at its isolator and disconnected. The dishwasher is different: it is hard-wired into a junction box, so disconnection means isolating the correct circuit at the board, proving dead, and disconnecting there. You must identify the circuit positively, not by guessing from an unlabelled board. If you cannot identify it, the board needs labelling or testing first.
So: yes in principle, but only after the switchboard is assessed, circuits identified, and isolation proved. Record what you isolated.
2. What must happen before reconnection, and what records do you issue?
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Before reconnection, the flood-affected equipment and wiring must be assessed. Appliances that were immersed or have wet insulation and controls may be uneconomical or unsafe to reuse, and the manufacturer's guidance on flood exposure should be followed. The fixed wiring, junction box, and isolators need inspection and testing by an electrician, and the circuit protective device rating and earthing must be confirmed.
Reconnection should only occur when the equipment is dry, tested, and confirmed safe, and when the supply is verified. For the hard-wired dishwasher, the junction box must be accessible and correctly terminated. Issue a certificate or record of the disconnection and reconnection as required by your authorisation, listing the circuits, the equipment, test results, and any limitations. Advise the owner in writing that the switchboard and flood-affected wiring need a licensed electrician's assessment, so the record shows you flagged it.