How to Replace Wires in a Prefabricated Slab House

Replacing wires in a prefabricated slab house requires careful operation and can be carried out according to the following steps:

Preliminary Preparation

• Confirm the aging condition: Observe the appearance of the wiring. If the insulation layer is cracked, overheated, or if electrical appliances trip frequently, sockets overheat, especially if the wiring has been in use for over 20 years, replacement is necessary.
• Prepare tools and materials: Prepare insulating pliers, screwdrivers, a multimeter, new wires (4 square millimeter copper wires for high-power appliances like air conditioners), wire threading tools, insulating tape, etc. The wire specifications should comply with national electrical standards.
• Develop a wiring plan: Plan the wiring route based on the house layout, taking the shortest path possible, avoiding water pipes and gas pipelines. Mark the locations of sockets and switches, and arrange separate wiring for high-power appliances.

Power Disconnection and Removal

• Complete power disconnection: Turn off the main switch in the distribution box and use a multimeter to check if the wiring is live. Never operate on live wires. Alternatively, cut off the power at the electrical panel or unplug appliances to disconnect the power.
• Remove old wires: Start from the distribution box and remove the old wires one by one, noting the original wiring connections. If the old wires are difficult to remove, use the method of pulling new wires through with the old ones. First, remove the protective components on the outer layer of the prefabricated slab, confirm the wire positions and connections, then disassemble the plugs or connectors connecting the wires, and remove the old wires from the prefabricated slab.

Wiring and Construction

• Wire threading operation: Use a wire threading tool to thread the new wires into the conduit. Ensure that the number of wires in the same conduit does not exceed 40% of the conduit's cross-sectional area to prevent overheating. Understand the connection method and specifications of the new wires to ensure they match the original wires. Pull the new wires into the prefabricated slab through the previous conduits.
• Connect the wiring: Connect the sockets, switches, and lighting fixtures according to the original markings. Connect the live wire to the switch, the neutral wire to the socket, and ensure the ground wire is reliably grounded. Wrap the connectors with insulating tape. Connect the plugs or connectors, and finally reinstall the outer protective components.

Precautions

• Pay attention to the wire specifications when replacing them. Choose appropriate wires and do not exceed the specifications or capacity limits of the original materials.
• Ensure that the wire connections are firm to avoid problems such as loose connections or wire breakage.
• Exercise extreme caution during operation. Do not cut too many slots in the prefabricated slab, and strictly prohibit workers from cutting horizontal slots, as this may cause the prefabricated slab to break, posing safety risks to all rooms above.