non-existant #8 pool bond conductor

[dan filipi]

We've been doing alot of swimming pool upgrades lately, most times the #8 bond conductor isnt connected to ANY of the equipment. Scarey, but at least it exists to be corrected.

Anyway,this current job is upgrading all electrical to current code at the pool. The pool was built early 60's, no light GFCI, aluminum Bell box as deck box.
The #8 bond is nowhere to be found, maybe buried in concrete, who knows, and it may be that it was never installed to the equipment from the bonding grid back in the 60's.
I need to tie into the bonding grid in some way.
In looking through article 680.26 Bonding.
680.26 (C) states "The common bonding grid shall be permitted to be any of the following: (# 4 states) "Rigid metal conduit or intermediate metal conduit of brass or other identified
corrosion -resistant metal conduit".
The way I'm understanding this is, If I clamp to the light niche brass riser conduit, this is a recognised and acceptable point to tie into the bonding grid. Is this an accurate understanding?
My concern here is that if the pool steel, light niche etc. were not properly bonded together when the pool was built, by my tieing into the brass pipe to bond the motor, is there any chance am I actually CREATING a difference in ground potential if structural bonding was not done? I dont think so but want to be certain.
All of the equipment conduits are being rewired so all EGC connections will be verified done properly at that point.

Any input much appreciated,

Dan

[ January 26, 2005, 06:59 PM: Message edited by: danl ]

 

[dan filipi]

Re: non-existant #8 pool bond conductor

anyone?

 

[jimwalker]

Re: non-existant #8 pool bond conductor

Sorry but not sure how to get around that.Any chance of drilling up near top till you hit rebar.perhaps a stud finder or metal detector

[ January 27, 2005, 09:15 PM: Message edited by: jimwalker ]

 

[dan filipi]

Re: non-existant #8 pool bond conductor

Good idea Jim,
I know a Jim Walker, do you know Brian Filipi?

We went ahead with the bond from the brass deck riser to bonding lug on the filter motor.
Let's assume there isnt any way to get to a rebar for a moment.

Just throwing this out looking for a solution.
Is there a way to test in such a way that we can look for a resistance value between say, the metal pool light trim ring whilst in the water and maybe the metal filter housing? The filter being full of water.

I'm realizing too now that the brass riser from the wet niche is in itself acting as a grounding rod, so even if the structural steel is not mechanically 'tied' to this riser, the conductance of the soil itself will complete the path to an extent, whether this is recognised or the resistance is within an acceptable limit is another story, and at this point unknown.

I've concidered calling in a pool pro but my experiences with these guys regarding bonding, motor grounds and GFCI's have shown that I know more than they do. Even the pool builders. They build em from scratch following the code but dont have experience in retrofits or upgrades/corrections.
Maybe a call to the code desk is in order.

Well, the light fixture now needs to be replaced, trips GFCI, so I'll see if there's a low voltage replacement, and also recommend a double insulated filter motor be replaced with what's there.
I could GFI everthing also.

[ January 28, 2005, 12:32 PM: Message edited by: danl ]

 

[jimwalker]

Re: non-existant #8 pool bond conductor

no i dont know him.Is there any metal hand rail on this pool ? might check for continuity from it to light shell.If open i suspect there was never a bond wire.

 

[dan filipi]

Re: non-existant #8 pool bond conductor

No hand rail, diving board or metal hooks.
I dont think there are any metal covers or metallic objects other than filter motor and underwater light. The filter housing is metal but no direct connection other than PVC lines which extend underground.

mmm, just had a thought, PVC is newer than the 60's. The pool must have had been replumbed. Maybe this contractor can be dug up and questioned.

 

[jimwalker]

Re: non-existant #8 pool bond conductor

why not try this,have it checked for a permit.If it had one i would asking if a bond was required back then.Anyone have a code book that far back ?

 

[dan filipi]

Re: non-existant #8 pool bond conductor

Thanks for your input Jim, You have some very good ideas.

I wonder how far back permits are kept on file at LA B&Safety?

After another site visit Friday I see that the deck is about 7 feet wide so I dont think there's any way to get to the original stuctural steel without excavating a tunnel under the deck to the main pool concrete wall. I think pool walls are 2-3 feet thick so this would mean a 4-5 foot tunnel.
There will be an addition coming off the rear of the house which may be in near proximity to the pool deck, in which case this might be the time to locate pool steel when I can have the G.C's laborers do the digging