National Electrical Installation Standards

Standards as High as Your Own

Friday, June 5, 2020


Hi Code People,

I need your help. I have a fused switch on the back of my house for an A/C unit and it has two short sections of copper pipe installed where each fuse is supposed to be, I think. Is there a problem here or is this okay? Is there an electrical code that addresses this?

Martin Peters



Hi Martin,

Thanks for sending the question. The short answer is yes this is a problem. Check the nameplate of the air conditioning equipment for a maximum fuse size and place that size fuse within the fuse holders of the switch. Be sure to shut the power off before installing the fuses. That’s a good start, but there is much left that is unknown about this whole situation, so we recommend contacting a licensed electrical contractor or electrical inspector to check this out for you for Code compliance and safety. Some related Code rules are found in the National Electrical Code in Sections 440.4(B), 240.4, 110.3(B) to name a few. 

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