National Electrical Code

Spa and Hot Tub Bonding

Dec. 15, 2016

Interpreting the intent of the National Electrical Code

All references are based on the 2014 edition of the NEC.

Trying to understand the bonding requirements for indoor spas and hot tubs can be very challenging. I find this problem especially true when trying to figure out what is required by Sec. 680.43(D)(5).

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Per Sec. 680.43(D), there is a list of five items that need to be bonded together. The first four are relatively easy to understand, but that fifth item can be confusing. It states, “Electrical devices and controls that are not associated with the spas or hot tubs and that are located less than 5 ft from such units; otherwise they shall be bonded to the spa or hot tub system.” Does this mean that a wall-mounted electric heater/blower with a built-in thermostat would need to be bonded to the hot tub system if installed within 5 ft of the hot tub, but also require bonding even if it was installed more than 5 ft from the hot tub? The Code literally seems to require bonding for both scenarios. However, I don’t think this is the intent of the Code.

I looked back through some previous editions of the NEC. From 2002 to 2014, the wording was virtually identical. Then I found some wording about bonding for indoor spas and hot tubs in the 1999 Code that seems to help clarify this situation. Section 680.41(d)(5) from the 1999 NEC states, “Electrical devices and controls not associated with the spas or hot tubs shall be located a minimum of 5 ft away from such units or be bonded to the spa or hot tub system.” Based on this finding, I don’t believe the bonding requirements near the spa or hot tub are intended to extend beyond 5 ft from the spa or hot tub.

Unfortunately, the confusion returns when we read Sec. 680.43(E) regarding what methods we could use to perform this bonding. This Section states, “All metal parts associated with the spa or hot tub shall be bonded by any of the following methods.” It then describes the three methods that are acceptable. So does this rule apply to our wall-mounted heater scenario? Should the heater be considered “associated with the spa or hot tub,” or is Sec. 680.43(D)(5) for bonding of electrical equipment that is NOT associated with the spa or hot tub?

I believe bonding in accordance with Sec. 680.43(E) should apply when electrical equipment is installed within 5 ft of the spa or hot tub. However, you should check with your AHJ for his or her interpretation of this situation.

About the Author

Russ LeBlanc | Owner

Russ started in the electrical trade as an apprentice in 1985. He worked his way up to become a Journeyman Electrician and then eventually became a Master Electrician and Licensed Construction Supervisor. In 1999 Russ become an Electrical Instructor for The Peterson School of Engineering in Massachusetts where he developed his passion for teaching, and quickly became Department Head of Electrical Instruction. Russ has taught thousands of apprentices, electricians, engineers, inspectors, and other electrical professionals during his career as an instructor. He continues to provide electrical professionals with Electrical Code seminars, Arc-Flash Awareness training seminars and educational material through his LeBlanc Consulting Services in North Reading, MA whose specialty is educating electricians. He has been an active member of the NFPA Electrical Section and has authored hundreds of National Electrical Code proposals and comments which have become Code rules to improve the safety for the electrical industry. Russ is also an IAEI certified Electrical Inspector.

Please visit www.russleblanc.net for more information.