• Reading Wire Terminals LIKE A BOOK

    July 1, 2004
    by Kevin V. O Have you ever checked a single-phase compressor, only to check the wiring terminals and find the wires burnt off at least one of the terminals?

    by Kevin V. O’Neill

    Have you ever checked a “dead” single-phase compressor, only to check the wiring terminals and find the wires burnt off at least one of the terminals? If only one of the wires is off, it’s easy enough to reconnect it. However, if two or three wires are burned off the terminals, it’s not always obvious which wire goes to which terminal.

    Fortunately, there’s an easy way to determine the terminal arrangement in such cases.

    On all single-phase compressors, the terminal arrangement is always in the same order and reads like a book: from left to right, top to bottom.

    As shown in the illustrations here, the arrangement is always C-S-R (Common - Start - Run). This arrangement holds true for single-phase compressors from all manufacturers.

    Even if the terminal label is gone, you can always trace the wires back to the capacitor and contactor, and determine where they go on the compressor. n

    Kevin O’Neill, CM, is co-owner of O’Neill-Bagwell Cooling & Heating, Myrtle Beach, ns AHe has 27 years experience in the HVAC service business and is a 20-year member of RSES. Kevin can be reached at 843/385-2220, e-mail [email protected].