Things You'll Need:
- Christmas Tree Lights Bulbs
- String Lights
- Bulb Testers
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Step 1
Replace burned-out bulbs immediately. They can cause the other bulbs to heat and shorten the lives of all the bulbs on the string.
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Step 2
Buy a bulb tester and use it to check any suspect light. Make sure all the bulbs are firmly fastened in their sockets.
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Step 3
Unscrew any defective bulbs.
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Step 4
Replace bulbs with the same kind. Don't mix C-7 and C-9 bulbs, for example.
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Step 5
Inspect every string for damage to the insulation on the wire or smashed light sockets.
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Step 6
Throw away any damaged string you find. The few dollars you might save are not worth the risk of a house fire.







