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Mitsubishi Mini-split Branch Box question
Residential 5 port Mitsubishi branch box: PAC-MKA51BC
If only 4 of the 5 ports are used, does it matter which ones? The install manual sort of insinuates that you should use A, B, C and D and leave E unused, although it sounds more like a recommendation than a requirement. My installer used A, B, D and E and left C unused, presumably because port E has a 1/2" gas line (the other 4 are 3/8") and one of the inside units was larger and required a 1/2" line. That way, he didn't need to install a 3/8" to 1/2" converter pipe.