pool electrical questions

[mound]

caveat: I'm not doing new work, or even trying to change anything, I'm just looking over how things are done on the existing equipment at the new house I moved into and curious about something.

The pool is fiberglass, inground, surrounded by concrete. All plumbing is plastic. Only metal in site is the handrail at the steps into the pool. There is also a light built into the pool shell which must be metal, but it doesn't work. I'm unclear if it's a bad bulb or not, but when I try to flip it on, the breaker for it trips immediately. I'm just ignoring this for now and leaving its breaker off. 

Otherwise there's a sand filter, pump, and gas heater in a little room together with a small load center holding a couple breakers for the pump/heater/light.  The box has separate neutral and ground bars. The box is fed from a 30amp breaker in the main panel using #10 THHN through a PVC conduit. 

My question specifically is about the heater and bond. 

I always understood bonding things as relates to pools as connecting pool pumps & heaters and any other metal parts with the pool shell itself and even the water to put everything at the same potential.  

The heater has red/green/black all going into the control panel to power it.  It also has a bare copper (#8) connecting a lug on the chassis of the heater, to the neutral bar in the electrical box. 

That's it. That's all I see anywhere that says "bond" to me.  I don't see any evidence around the metal steps handle that anything is bonded, nothing anywhere.

So what purpose does bonding the heater shell to the neutral bar in the load center serve?

[srv52761]

Can’t help you.
But, when you said “bare copper… neutral” I kinda did a double take.

[mound]

Can’t help you.
But, when you said “bare copper… neutral” I kinda did a double take.

Yah - the bonding wire is bare copper, twisted/stranded looks about #8 and it goes from the bonding lug on the heater directly to the neutral bar in the service panel. 

Is it wrong?

[mound]

I took at look at the hot tub too.  It has (4) #6 THHN in PVC conduit running to it from a sub-panel in the basement.  The hot-tub has two hots, dedicated ground and also a bonding lug, which goes to the neutral bus in the sub-panel. (in this case it's insulated)

[Mr_Mike]

I don't think those bonding wires should go to the neutral ever. If I recall my old house's pool wiring, the bonding wire was attached to a ground rod as was all other metal things around the pool. Firstly I would check on-line for prescriptive wiring diagrams of how it should be wired. Then, I'd remove those bond wires and, if necessary, bond to an earthed rod.

My existing spa is wired like any other 240V load. Neutral to neutral buss, ground to ground buss.

FYI your below water light. Generically, underwater lights have a long pigtail and the light/waterproof pigtail are snaked through conduit to an above ground weather resistant J-box probably just beyond the pool deck. Then, from that j-box traditional wiring goes to the appropriate breaker panel. Find that j-box and disconnect the light. Try the breaker. If OK, your light is toast. Pull it out of the housing and get a replacement. This can be done with the pool full of water if you can hold your breath long enough.


Side note: When I rehabbed my old pool, I purposely used a PVC ladder so I didn't need to cut up concrete the provide a proper bonding path.

[mound]

I don't think those bonding wires should go to the neutral ever.  If I recall my old house's pool wiring, the bonding wire was attached to a ground rod as was all other metal things around the pool.  Firstly I would check on-line for prescriptive wiring diagrams of how it should be wired.  Then, I'd remove those bond wires and, if necessary, bond to an earthed rod. 

My existing spa is wired like any other 240V load.  Neutral to neutral buss, ground to ground buss. 

FYI your below water light.  Generically, underwater lights have a long pigtail and the light/waterproof pigtail are snaked through conduit to an above ground weather resistant J-box probably just beyond the pool deck.  Then, from that j-box traditional wiring goes to the appropriate breaker panel.  Find that j-box and disconnect the light.  Try the breaker.  If OK, your light is toast.  Pull it out of the housing and get a replacement.  This can be done with the pool full of water if you can hold your breath long enough. 


Side note:  When I rehabbed my old pool, I purposely used a PVC ladder so I didn't need to cut up concrete the provide a proper bonding path.

Thanks Mike.  I actually did just that the other day - located the Jbox (it's below the diving board) and disconnected the pigtail. My light must be toast!

To the bonding..  after clearing away more of the mess in this little pool room (which somebody had half hazardly drywalled which is ridiculous since it's full of mold) I did find what I believe to be the bonding line.  There's a thin metal tube (no more than 1/2" wide) coming up out of the concrete floor (hidden behind this nasty piece of useless drywall I pulled out). There's a length of #8 insulated copper coming up out of this tube and it's connected directly to the neutral bus in the panel. Then the bare #8 copper which was bonding the heater is also attached to the neutral bus right next to it.

Assuming the #8 copper coming out of the concrete with nothing else around it is attached to whatever sort of bonding grid is surrounding the pool. It seems like that should have simply gone directly to the pump and heater, rather than to the neutral bus of the panel.. somebody did it this way for a reason I have to believe.

[Mr_Mike]

Do your own research as screwing up bonding can kill you, but...I did a little digging. Bonding just hooks all the metal stuff together and does not need to be attached to panel ground nor to a ground rod. It just makes sure the water and the pool ladder are at the same potential, whatever that potential is. That said, you have to ground the pump motor, the light, and the heater. Those are also required to be bonded. Thus, ground and bond are at the same potential too. Apparently Canada requires the bonding system to be grounded at the panel, but the US does not. However, the US also does not forbid it.

What I would do is move your bonds to the ground buss bar from the neutral bar. Then, your grounds and any bonded items are all together, which is good. What you decide to do may be different.

[Roly]

Do your own research as screwing up bonding can kill you, but...I did a little digging.  Bonding just hooks all the metal stuff together and does not need to be attached to panel ground nor to a ground rod.  It just makes sure the water and the pool ladder are at the same potential, whatever that potential is.  That said, you have to ground the pump motor, the light, and the heater.  Those are also required to be bonded.  Thus, ground and bond are at the same potential too.  Apparently Canada requires the bonding system to be grounded at the panel, but the US does not.  However, the US also does not forbid it. 

What I would do is move your bonds to the ground buss bar from the neutral bar.  Then, your grounds and any bonded items are all together, which is good.  What you decide to do may be different.

I would first check what the local inspector wants.  The pool grounding/bonding of pools issue is not cut and dried as it varies from one are to another.  The other thing that enters the picture is the sub panel is fed with 4 #10's, # 8 is required for bonding also distance from main panel.  I don't know the answer but if this was inspected and your not having any issues I would find out what is correct with the inspector before changing anything.  Roly

[mound]

I would first check what the local inspector wants.  The pool grounding/bonding of pools issue is not cut and dried as it varies from one are to another.  The other thing that enters the picture is the sub panel is fed with 4 #10's, # 8 is required for bonding also distance from main panel.  I don't know the answer but if this was inspected and your not having any issues I would find out what is correct with the inspector before changing anything.  Roly

Thanks all. To be sure, I'm not actually changing anything (not yet anyway!), just trying to understand what was done. I've not personally had it inspected, the house came like this (but I also don't see any inspection stickers anywhere). The pool itself is probably 30 years old, but I can see somebody re-wired everything around 2007 (and left a lot of unused junk hanging around with it)

At my previous pool, everything was bonded with a solid uninsulated #8 copper wire that didn't tie back to any panel box or any sort of metal rod in the ground that I could find - it just tied all the metal things together and the pump/heater also had dedicated equipment grounds.  Maybe the electrician was from Canada. haha. The lonely #8 copper wire coming up out of the concrete is insulated (and stranded) which seems odd to me as well since everything I've read about bonding says to use #8 solid bare copper. (I'm assuming this is the bonding wire why else would a single random conductor be exiting the concrete deck near the pool mechanicals?)

I mentioned the bond was tied to the neutral bus. Well looking closer, the neutral and ground are connected as well in this box. 

Interestingly, in this little breaker box for the pump/motor/heater, the incoming #10 (red/black/white and green orange romex) has the ground and neutral all tied together, with the bond, on the same bus. This pool panel is all fed by a 30amp breaker inside a 100amp sub-panel in the house.  I confirmed that the ground and neutral busses are isolated on that sub-panel.

So for whatever reason it seems ground, neutral and bond are all simply tied together at the pool room.

[Danny in Houston]

I also recently bought a house with a dead lamp in the pool - for now I have an air gap in place until I get it fixed.  I worked for a few years as an apprentice electrician, I'm a licensed engineer, and I consider myself quite handy.  

However, when it comes to electrical for pool equipment, I use a highly qualified electrician.  Same for dental work, heart surgery, etc.