Disconnect fuse requirement


Old 11-11-17, 12:42 PM
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Disconnect fuse requirement

To connect my Mitsubishi MSY-GL24NA 2 ton 240V mini split inside air handler from the outside condensing unit, I'm using a metal clad with PVC jacketed 600V direct bury cable with three 14 gauge THHN conductor & 14 gaugeTHHN ground cable. Two conductors are 120V each and the third is 12 to 24V communication wire back to the outside condensing unit. Rather than use a fused disconnect switch on an interior wall, I would like to use a motor rated three wired terminal switch, in a 4" metal box without any fuses adjacent to the inside air handler. My inside air handler has a 15 A fuse and a varistor across the two 120v wires on the indoor load LD201 terminal P.C. board. It's fuse is the very first thing on the board, right next to the exterior power connections of the terminal board. Power to the inside air handler unit is for the fan motor, vane control motors, and transformers, but can only pull a couple of amps or less at most. As far as I can tell Mitsubishi only wants an interior not fused disconnect switch, but should the electrical inspector want additional fuses?
Old 11-11-17, 01:22 PM
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Your Mitsubishi unit just requires a disconnect for servicing only. It is not required to be fused as the outside unit is protected and that protects the inside unit,

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