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Where refrigerant leaks usually are on a split system
A split AC or heat pump with numbered common leak spots: Schrader valve cores and caps, service valve stems, flare and field braze joints, the evaporator coil tube sheets and U-bends, rub-outs where tubing touches the cabinet, the filter drier, the condenser coil's lower rows, and the TXV sensing bulb capillary.
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