Hydro pump bonded to water feed???

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M. D.

M. D.

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I just got this question wrong . My answer (b) was based , in part , on what I thought I learned at this forum ,...... so does the external metal pump casing and the metalic water supply need a #8 bond ? I say yes

680.74 Bonding Hydromassage Bathtubs
question id# 0274




Metal piping systems that supply Hydromassage bathtubs must be grounded


Article 680.74 in the 2002 NEC? was changed by deleting wording that required listed double-insulated pumps to provide a ?means for grounding internal, non-accessible, non-current carrying metal parts.? This change was supported by comments that pointed out that the 2002 NEC? language was appropriate for swimming pool pumps which are not-double insulated. Requiring bonding of internal parts of listed double-insulated hydromassage pumps would violate their listing.
The change was unanimously approved because the panel believed that an increased level of safety was provided for these installations when listed double-insulated hydromassage pumps were connected to a power source by means of a three wire cord that included an equipment grounding conductor.


Question 274.
Which of the following components of a hydromassage tub are required to be bonded together by a #8 AWG copper conductor?
A: Internal non-current carrying metal components of a listed double-insulated hydromassage pump
B: Metal piping on the tub that is in contact with circulating water
C: Metal piping that supplies water to the tub
D: Both b & c are correct

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Choice B is incorrect

(d) is correct. The change in article 680.74 omitted the requirement for bonding internal components of listed double-insulated hydromassage pumps because this would violate the listing of the pump.

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Can I change my mind again???

I think I see the error I made;
the metal supply system is bonded to the metal circulating system and the motor is not , and should not be , connected to the bond wire because it is a double insulating type motor and to do so would compromise the listing. We bond the two systems because we are basically "sitting" in one and can touch the other.

Light dawns on Marblehead
 
M. D. said:
Can I change my mind again???

I think I see the error I made;
the metal supply system is bonded to the metal circulating system and the motor is not , and should not be , connected to the bond wire because it is a double insulating type motor and to do so would compromise the listing. We bond the two systems because we are basically "sitting" in one and can touch the other.

Light dawns on Marblehead
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There is no requirement to bond the metal piping system supplying water to the tub unless that system is connected to the water circulation system. If the metal piping supplies hot and cold water to a faucet and the tub recirculation piping system is nonmetallic than no #8 bonding is required. Being able to "touch the other" does not make bonding that piping a requirement.
 
M. D. said:
. . . because it is a double insulating type motor . . .
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Where does the question say that it's a double-insulated motor?

M. D. said:
Question 274.
Which of the following components of a hydromassage tub are required to be bonded together by a #8 AWG copper conductor?
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Larry, I believe hydro tub motors are required to be listed as double insulation type .
 
Infinity, would you agree that if the circulation system is metal and the supply piping is metal that these two require bonding ???

If they were connected to one another ,....I don't see the reason to bond them.

Which of the answers do you think is correct??
 
M. D. said:
Infinity, would you agree that if the circulation system is metal and the supply piping is metal that these two require bonding ???

If they were connected to one another ,....I don't see the reason to bond them.

Which of the answers do you think is correct??
Click to expand...


They are not required to be bonded together. Just because you have metallic hot and cold water pipes feeding the tub's faucet does not mean that they require any bonding. You fill the tub with the faucet, its metallic supply piping is not connected to the water circulation system therefore it does not require bonding.

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 than 8 AWG solid.
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"All metal piping systems and all metal parts in contact with the circulating water shall be bonded together".....

The metallic supply piping system needs to be bonded to any metal parts in contact with the circulating water . If there are no metallic parts contacting the circulating water no bonding to supply system is required , if there are metal parts contacting the circulating waterthe two shall be bonded together.

How would you have answered the question????

I'm not sure they both have to be in contact with the circulating water in order to require bonding ??

The question comes from an online seminar I'm taking to comply with New Hampshire's regulations for license renewal .

Notice the supply piping system in the question is suppling water to the tub and not to a circulating system .
 
Notice the supply piping system in the question is suppling water to the tub and not to a circulating system
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Read the above quote again. You've answered your own question. The supply water piping is not part of the circulating system therefore it does not require bonding.
 
Then what they say is the correct answer is wrong,... in your opinion.

B: Metal piping on the tub that is in contact with circulating water
C: Metal piping that supplies water to the tub
 
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M. D. said:
Then what they say is the correct answer is wrong,... in your opinion.

B: Metal piping on the tub that is in contact with circulating water
C: Metal piping that supplies water to the tub
Click to expand...

Bonding in answer C is not required, in B it is required.
 
I disagree, they are required to be bonded together.

"All metal piping systems and all grounded metal parts in contact with the circulating water...."

The supply is "a metal piping system" and if there is a grounded metal part contacting the circulating water they are required to be bonded together.
 
There is no reason to bond metal piping or grounded metal parts that are remote from the tub. The bonding of parts at the tub places those objects at the same potential thus reducing the likelihood of touch or step voltages from occurring in and around the tub. Bonding to remote piping would serve no useful purpose.
 
M. D. said:
I disagree, they are required to be bonded together.

"All metal piping systems and all grounded metal parts in contact with the circulating water...."

The supply is "a metal piping system" and if there is a grounded metal part contacting the circulating water they are required to be bonded together.
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Ok you open the faucet and fill the tub. Now you turn off the faucet and start the circulating pump. How is the supply water piping in any way connected to the circulating water system? It's not. Just because you can touch the metal faucet does not mean that it requires any type of bonding at the tub with a # 8 conductor. This is a hydromassage tub not a pool.
 
Pierre C Belarge said:
All metal piping systems AND all grounded metal part in contact with the circulating water shall be bonded together...

The AND in the sentence means both parts of that sentence need to be bonded together.
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Pierre I disagree. By your interpretation any metal piping system including one in the basement would require bonding too.
 
Thank you Pierre,
I do not think both are required to be in contact with the circulating water in order to require bonding & niether do the folks who created the question approved in 14 states to provide contiuing education .
 
M. D. said:
Thank you Pierre,
I do not think both are required to be in contact with the circulating water in order to require bonding & niether do the folks who created the question approved in 14 states to provide contiuing education .
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You should read this originally posted by Georgestolz:

Any metal piping system in contact with the circulating water is to be bonded.

Any metal piping system not in contact doesn't.

See the 2005 Report on Comments that changed this:

Quote:
__________________________________________________ ______________
17-183 Log #732 NEC-P17 Final Action: Accept in Principle
( 680.74 )
__________________________________________________ ______________
Submitter: Gary Siggins, Underwriters Laboratories Inc.
Comment on Proposal No: 17-152
Recommendation: The Panel Statement regarding the rejection of proposal
17-152 indicated they believed a double insulated whirlpool bath pump provided
an increased level of safety. Although this is the case for above ground
storable and non-storable swimming pool pumps, I believe it is not the case
with whirlpool baths utilizing double insulated pumps. The pump designs and
their installations are different.
Whirlpool bath pumps are not accessible by the bathtub occupants and are
required by UL 1795 to have their live parts above the mounting service in the
event of a leak. They are also required to have their internal metal parts that
might become energized in a failure (the motor shaft in particular) isolated
from the water. An internal failure of the motor would not produce the same
hazards as an outdoor storable pool unit that is accessible and may have wet
surfaces. The grounding of internal dead metal parts, therefore, is not needed.
Due to the requirements on the double insulated bathtub pumps and their
mounting in UL 1795, the text from 680.74, ?and providing a means for
grounding internal nonaccessible, non-current carrying metal parts? should,
therefore, be deleted.
Substantiation: Present text requires substantial modification of the pump
motor without an overall increase in the safety of the complete whirlpool bath.
Panel Meeting Action: Accept in Principle
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 than 8 AWG solid.
Panel Statement: The need for bonding in a bathroom differs from the need
for bonding in a pool area. Electrical equipment of a hydromassage bathtub is
not accessible to users of the tub. Only parts that can cause a voltage gradient
in the bathtub need to be bonded. Section 680.74 has been concisely reworded
to require the bonding of only the parts that present a risk of creating voltage
gradients in the hydromassage bathtub. The panelʼs action on 17-183 supersedes
the panelʼs action on ROP 17-153.
Number Eligible to Vote: 10
Ballot Results: Affirmative: 10
__________________
-George
​
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​
 
I know the handbook is not the code but, here goes.

"The bonding requirement for hydromassage bathtubs requires interconnection between metal piping systems and metal parts associated with the water recirculating system only at the hydromassage bathtub location.

As is the case with swimming pool bonding, this section does not require the installation of a bonding conductor from the hydromassage bathtub motor to the service equipment or panelboard from the hydromassage bathtub branch circuit originates even if there is no metal piping or metal parts in the vicinity of the hydromassage bathtub.

The bonding required by 680.74 is intended to create a local equipotential plane, and the equipment grounding conductor of the branch circuit supplying the hydromassage bathtub provides the path for ground fault current.

Trevor I'm not sure your concern about other piping would be in the scope of the article.
 
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