Bonding gone wild - Spa Tub

[sfav8r]

We just installed two jacuzzi tubs with double-insulated motors and all PVC piping. They are fed from a grounded GFCI circuit. I don't believe this requires bonding of any kind because there are no metalic parts and the motor is double insulated. The unit does not even have a bonding jumper. HOWEVER, I have learned from experience to put my own lug and bond to the cold water pipe because it's not worth arguing with an inspector over. But today, we failed the inspection because we didn't bond to the hot water pipe too. He says the NEC states ALL metal pipes (not to get another thread going about the wording of this section about being in contact with circulating water). The pipes are already bonded at the hot water heater, why would we bond them again?

First question. Do you think the system as described needs to be bonded at all?
Second Question: Does anyone else bond cold AND hot water pipes to the motor?

Thanks.

 

[infinity]

No bonding is required by the NEC. You will hear many other opinions however.

 

[M. D.]

The double insulated pump does not require bonding.

17-167 Log #618 NEC-P17
Final Action: Accept in Principle
(680.74)​

__________________________________________________ __________​

Submitter:​

Michael J. Johnston, Plano, TX​

Recommendation:​

Revise text to read as follows:
680.74 Bonding. All metal piping systems supplying hydromassage bathtubs,
including metal piping and all grounded metal parts in contact with the
circulating water, shall be bonded together using a copper bonding jumper,
insulated, covered, or bare, not smaller than 8 AWG solid. The bonding jumper
shall terminate at the pump motor on a terminal for this purpose.
FPN: The 8 AWG or larger solid copper bonding conductor shall not be
required to be extended or attached to any remote panelboard, service
equipment, or any electrode.​

Substantiation:​

The proposed revision is for clarification purposes. There
continues to be considerable confusion and inconsistency in how this
requirement is being applied in the field. The common practices currently
include bonding the hot and cold water piping supplying the tub to the terminal
lug on the pump motor (other than double insulated types). The current text is
being viewed and interpreted by some as only requiring ?metal piping systems
and grounded metal parts in contact with the circulation water? to be bonded.
The piping for the circulation water of a hydromassage tub is typically
nonmetallic. The questions arise as to the requirement for bonding the hot and
cold water supply piping system that is connected to the tub. If the objective is
to place all metal piping and metal parts such as faucets and valves associated
with the hydromassage tub at the same equipotential plane, then the Code
should clearly require that, and not leave users with any question as to what is
required to be bonded and where the bonding jumper is required to be
connected. The proposed FPN is the same one that follows 680.26 to help
clarify that this bonding conductor does not have to be routed to a panelboard
or service equipment or grounding electrode.
Note: Supporting material is available for review at NFPA Headquarters.​

Panel Meeting Action: Accept in Principle
Panel Statement:​

See panel action on Proposal 17-166.​

and here is the language they think clears it up,... taken from 17-166

Revise 680.74 to read as follows:

680.74 Bonding. All metal piping systems and all grounded metal parts in
contact with the circulating water shall be bonded together using a copper
bonding jumper, insulated, covered, or bare, not smaller that 8 AWG solid. The
bonding jumper shall be connected to the terminal on the circulating pump
motor that is intended for this purpose. The bonding jumper shall not be​

required to be connected to a double insulated circulating pump motor. The 8
AWG or larger solid copper bonding jumper is required for equipotential
bonding in the area of the hydromasage bathtub and shall not be required to be
extended or attached to any remote panelboard, service equipment, or any
electrode.​

​

 

[sfav8r]

Thanks,

How about bonding hot and cold to the tub? Has anyone else been told this?

 

[Dennis Alwon]

Thanks,

How about bonding hot and cold to the tub? Has anyone else been told this?

I am sure someone has required some poor slob to do that but it should not be necessary.

 

[cowboyjwc]

Thanks,

How about bonding hot and cold to the tub? Has anyone else been told this?

No bonding of the tub required and your hot and cold are bonded at the mixing valve.

 

[Oakey]

I have failed for not bonding the hot and cold pipes. I was on the job and just did it, now its just habit.

 

[nakulak]

I've been required to bond hot and cold in a couple of counties around here, not worth the argument, just did it.

 

[cowboyjwc]

That's the problem when inspectors don't think past the NEC. All you have to do is think for a minute and realize that the hot and cold are "bonded" or "interconnected" or what ever you want to call it, at almost every faucet.