On this page 4 sections
Bonding is metal to metal, not metal to earth
Bonding puts the metal parts of the house at the same electrical potential so current has a designed path back to the source when something faults. The earth connection is a different job. If those two words are being used interchangeably on a report, the report has not told you which work you actually need.
-
Grounded
A connection to the earth — rods, a Ufer, a metal water-pipe electrode. That is the grounding page. Driving a rod will not bond a water heater.
-
Bonded
Metal parts tied to each other and to the service: the main bonding jumper, water piping, gas piping, a water-heater jumper. This job. Article 250 Part V, not Part III.
-
Why the mix-up matters
An inspector or an insurer often writes “grounding/bonding” as one finding. They are two failure modes. We separate them on site so you are not sold an electrode for a missing jumper, or a jumper for a missing ground.
Send the letter or the inspection list. We name the actual missing connection before anyone prices a clamp.
A subpanel bonded twice is the dangerous bonding fault
The main bonding jumper — the screw or strap that ties neutral to ground — belongs in one place: the service. Downstream of that, repeating it is not “extra safe.” It puts current on the equipment ground that should never be there.
What we find
A subpanel with the bonding screw still in, or a strap left between the neutral bar and the enclosure. Neutral current then has a second path home — through the equipment ground, through metal piping, through anything bonded to the can.
The correction
Remove the extra bond, isolate the neutral bar, confirm the four-wire feeder, and leave the one correct bond at the service. It is a small correction with a large consequence if it is left.
Bonding corrections: water heaters, gas pipe, and CSST
Most bonding corrections are jumpers: short, listed connections that put piping and equipment on the same potential as the service. CSST is the one with a manufacturer history behind it.
-
Water-heater jumper
Hot, cold, and often the gas line at the heater get a bonding jumper so the piping system is continuous around dielectric unions and flexible connectors that would otherwise isolate it.
-
Metal water and gas piping
Interior metal piping is bonded to the service so a fault on that piping has a path back. The conductor is sized to the circuit that could energize it (NEC 250.104 / 250.122), not guessed.
-
CSST
Corrugated stainless steel gas tubing is bonded with a listed clamp and a heavier conductor because of a lightning-damage history the manufacturers documented. Arc-resistant jacketed CSST is the exception the listing spells out — we identify which product is on the wall rather than treating all yellow gas line the same.
When bonding is not the job
A bonding correction is a connection between metal parts. Two other pages own the neighbors.
The earth connection is what is missing
No rod, an orphaned water-pipe electrode after a PEX repipe, an undersized grounding-electrode conductor — that is grounding. A jumper at the water heater will not create an electrode.
The letter named the panel
If the underwriter flagged a Federal Pacific, a Zinsco, or the enclosure itself, send it through insurance corrections. Bonding may be a line item in that job; it is not the letter.
Something is tripping or shocking now
A live symptom is diagnosis. This job is the planned correction of a known missing bond, not the hunt for a fault.
Not sure this is the right job?
Tell us what you are seeing — what is tripping, what changed, or what you are planning — and we will tell you what the work actually is before anyone drives out.
Bonding questions
What is the difference between grounded and bonded?
Grounded means connected to the earth — that work is grounding. Bonded means metal parts connected to each other so they stay at the same potential. A house can have one and not the other, which is why they are separate jobs.
Why is a double-bonded subpanel a problem?
Neutral current is supposed to return on the neutral. A second bond at a subpanel lets it return on the equipment ground and on anything metal tied to the can. That is objectionable current on parts people touch.
Does CSST always need a bonding clamp?
Yellow CSST typically does, with a listed clamp and a conductor the manufacturer specifies. Arc-resistant jacketed products are listed differently. We identify the product on the wall rather than treating every gas line as the same.
Will this satisfy my insurance company?
We do the listed correction and document it. We cannot promise how an underwriter will respond. If you have a letter, send it through insurance corrections with the photos — we tell you what it is actually asking for.
Still not sure it is the right job? Call (279) 972-9272 — available 24 hours.
Serving 19 communities across the Sacramento area
Litel Electric serves homeowners throughout all 19 communities in our service area — from Davis and Woodland to Roseville, Folsom, and Elk Grove.
Get estimate
Tell us what is happening, or what you are planning. We read the details, tell you what else we need to know, and explain the next step before anything is scheduled.
- 01
You send the problem or the plan, with the address if you have it.
- 02
We reply with what it involves and what has to be seen in person.
- 03
Nothing is scheduled, and nothing is priced, until the equipment has been looked at.
- hi@litelelectric.com
- License
- CSLB #1115460 · C-10 electrical