Bonding question for our electricans in the group

[TroubleFreePat]

First, I understand each local entity has different codes. I also understand getting someone "local" to interpret them for me is probably going to be like pulling teeth with our township. So just trying to do my homework and educate myself a little. Any advice I get will absolutely be checked with the proper authorities (When I can find them!)

Regardless, here's my scenario. Looking to add a heat pump. Electrical service is already in place at the sub panel for the pool, so no long distance runs there. My question is on bonding.

I understand the basic difference between grounding and bonding. We have an in ground fiberglass pool. There was a bonding wire run around the perimeter of the pool before concrete was poured (I saw it). We have nothing metal in the pool that would require bonding (Ladders, handrails, etc.) We do have two LED lights, but all plastic.

All of the equipment on our pad is bonded. There is a special PVC pipe connector from the main drain that the bonding wire starts at. It then loops through the pump then to the sub panel box. On the sub panel box, it loops through a termination point on the outside of the box - it does NOT enter the box. From there, it then runs to what appears to be a ground rod.

That's where I get throw. Ground rod? Why? I did some digging and did find in a Hayward heat pump manual (Not the one I'm getting) this text -

"On some older pools, this substructure bond wire may not exist. In these cases, a 6 to 8 foot solid copper rod must be driven into the ground near the equipment."
(http://www.hayward-pool.com/pdf/manuals/EasyTempHeatPump-R-410A.pdf)

So now I'm really lost. I thought this was a no-no, but the more I read, the more it seems some places (Especially Canada) require a grounding rod in the bonding system. I thought that defeated the purpose. Anyway, I DO know that if there is a ground running around the perimeter of my pool, it does not appear run over to the equipment pad (Not sure if it should be or not, not finding anything on that one - if not, where does it terminate?)

Final question. This was really my original question when I began reading. If I add a heat pump, do I have to add a completely new bonding wire to all components on the pad so it's continuous? Or can I lug onto the existing bonding wire?

 

[Norcal Spearo]

I would go to the existing bonding wire.

 

[JasonLion]

You can connect to the existing bonding wire with an approved split bolt. It is the loop around the pool that needs to be continuous.

Canada does not require a ground rod, it requires that the bonding system be connected to the grounding system.

In most places ground rods connected to the bonding system are discouraged, though not prohibited. Every now and then you run into confusion about the disallowed/discouraged/allowed/required aspect of that, which mostly has to do with the rules changing over time.

One thing to keep straight: there is the grounding system, and the bonding system. They are separate wires belonging to separate systems. There may be a ground rod on the bonding system. That doesn't make it a grounding system, it is still a bonding system. Ground is never run around the pool, bonding is always run around the pool.

Do you know if you have a water bond or not? A water bond is a fairly new rule, which requires the bonding system to be connect to a metal plate in the water. Retrofitting one is probably not required, but it is generally a good idea.

 

[danpik]

Jason pretty much covered it. A ground rod, separate from the facility grounding system can be on a bonding system and will not cause any problems. As for your area requirements, it depends on what code cycle of the NEC Penn is on and if there are any addendums that may be local to your area.

 

[TroubleFreePat]

Thanks all, good information. Yes, the bonding system is definitely separate from the ground system. And we do have a water bond - it's on the incoming PVC from the main drain.