Thank you for your question regarding Ground-Fault Circuit Interrupter (GFCI) outlets and water coolers, it is our pleasure to help.
The National Electrical Code (NEC) Article 422.51 and 422.52 are very clear on this subject, you must have GFCI protection for water coolers. In fact, machines manufactured after January 1, 2005 must have integrated GFCI protection inside the circuitry of the system (see NEC 422.51). Depending on how your local inspector interprets the code (see NEC 422.52), you may be required to provide a dedicated GFCI outlet, even if the cooler has integral GFCI protection.
We would recommend that you install a GFCI and Arc-Fault Circuit Interrupter (AFCI) (see NEC 210.12) for your water cooler.
We hope this helps. If your should have any further questions, please do not hesitate to contact us again.
The Engineering Team at E&S Grounding Solutions
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