ECN Forum Forums Code Related Discussion NEC & other Code issues Hydro Massage Bathtub (HMBT)

2002 NEC Article 680.74

When I read this it says that I need to bond metal piping systems and pumps etc., together with a #8 solid copper conductor. It goes on to say that a double insulated pump shall not be bonded. Does this negate all bonding for the HMBT?

I got stung on this before here ;-)
If there is no electrical equipment to bond, I am not sure what you would bond the pipes to ... other than the normal 250.104 bonding.
After the death up in central Florida from energized steel framing (and the medicine cabinet) they are getting a little pickier about bonding in bathrooms. There really isn't much to bond tho, since we never see metal plumbing in 1&2 family.
I have thought about this since my l;ast spanking here and the only real rationale for a difference between a spa and a tub is the heater. That is a big difference. These are usually immersion heaters and there is a good opportunity to energize the water.

More of the sentence needs to be read. "Metal parts of listed equipment incorporating an approved system..."etc.
Field installed piping would not be part of the listed equipment in my opinion and would not be exempt from bonding.
The bigger problem is, to what would you bond the piping?
A grounded junction box ?
Or as gfretwell mentions just 250.104
Alan--

Alan, I came up with the same conclusion. The '05 makes it a little clearer when it talks about the "all metal piping systems and all metal parts in contact with the circulating water shall be bonded together".

I'm convinced that even under the '02 NEC we still need to bond thing (Piping, metal parts, heaters) even if we have a double insulated pump that would not get bonded.

I'll be looking at the installation manual the next time I have an inspection and see what they say about any bonding when there is a double insulated pump.