Change Summary

• New requirements were added for GFCI protection for swimming pool and spa gas-fired water heaters.

Expert Analysis

GFCI protection for personnel is not required for electric water heater installations as the risk of electric shock is considered adequately mitigated through the use of proper grounding provisions [see 680.6(3)] and the listing installation requirement for the use of current collectors on the input and output side of the heater. These current collectors have proven reliable to prevent unacceptable levels of current in the pool in the event of corrosion of the immersed heating elements of an electric pool heater. However, these current collectors are not present with a gas-fired swimming pool heater. The 125-volt branch circuit to a gas-fired water heater is susceptible to a loss of current and a ground-fault condition as much as any other piece of electrical equipment.

To address this issue, branch circuits serving gas-fired swimming pool and spa water heaters operating at voltages above the low-voltage contact limit are required to provide GFCI protection for personnel beginning with the 2017 NEC. This requirement adds a measure of safety to the end user of the swimming pool in future installations.

Some within the electrical industry, including some enforcers of the Code, have relied on the requirements of 680.22(A)(2) to enforce GFCI protection for receptacle outlets that provide power to pool heaters of permanently installed pools. This particular provision required GFCI protection for “receptacles that provide power for water-pump motors or other loads directly related to the circulation and sanitation system.” The argument being that a pool heater would fall into this category of “other loads directly related to the circulation and sanitation system.” Regardless if this is a legitimate Code interpretation or not, this new GFCI requirement for gas-fired water heaters will give users of the Code a strong, direct requirement for GFCI protection for this one heating aspect of the aquatic environment moving forward.