Bonding Water Heater

**chuck b** · 06-28-2011, 07:41 PM

Is it wise to provide a bond between the hot and cold water pipes of a water heater?

The electrical panel is for a 200-amp service, so should a #4 gauge wire be the right size then? Is it NOW correct to also bond the natural gas pipe along with the hot and cold pipes? Does doing so create any kind of hazard?

Thanks, Chuck

**ActionDave** · 06-28-2011, 09:50 PM

If your house is plumbed with copper or galvanized pipe you should have a bond to the cold water pipe already. A shower valve completes the bond to the hot water side.

The gas line will be sufficiently bonded by the gas appliance's electrical connection. This assumes you have an equipment ground on the circuit that provides power to the appliance.

When was this house built? Is the water line to house metal? What kind of gas piping do you have?

**chuck b** · 06-29-2011, 04:36 AM

Thanks for the information.

House is plumbed with copper with a jumper on each side of the water meter. The natural gas line in question by the water heater is of course not electric, but the nearby natural gas furnace is which the gas line also supplies. Not sure what you mean by a shower valve completing the bond.

Your comments?

Originally Posted by ActionDave

If your house is plumbed with copper or galvanized pipe you should have a bond to the cold water pipe already. A shower valve completes the bond to the hot water side.

The gas line will be sufficiently bonded by the gas appliance's electrical connection. This assumes you have an equipment ground on the circuit that provides power to the appliance.

When was this house built? Is the water line to house metal? What kind of gas piping do you have?

**jwelectric** · 06-29-2011, 09:03 AM

The only requirement for bonding a metal water pipe is found in 250.104 and this section requires the bonding point to be accessible.

There is no requirement to bond the hot to the cold as they both are from the same potable water system. If you are worried about the bonding taking place the valve that is used to turn the hot and cold water on at the shower does this bonding as well as other types of plumbing mixing valves and supports.

The gas pipe will need to follow the installation instructions that come with any flexible connections to the gas equipment. All 250.104 calls for is the equipment grounding conductor that is installed with the branch circuit conductors supplying a piece of gas equipment such as the heat.

**ActionDave** · 06-29-2011, 10:41 PM

Originally Posted by chuck b

Not sure what you mean by a shower valve completing the bond.

He said it better.

Originally Posted by jwelectric

There is no requirement to bond the hot to the cold as they both are from the same potable water system. If you are worried about the bonding taking place the valve that is used to turn the hot and cold water on at the shower does this bonding as well as other types of plumbing mixing valves and supports.

hj · 07-01-2011, 06:02 PM

Placing a bond between the hot and cold lines at the heater is ALWAYS a good idea. Many heaters start leaking because of "stray" currents passing from the hot side to the cold by going THROUGH the water heater, and since this is a high resistance path, it deteriorates the water heater. I once had a heater that lasted 4 months and when it failed it was like someone used a can opener on the top of the heater DIRECTLY from the hot outlet to the cold inlet. There is usually no sign of electrical activity to be detected, but after I installed a jumper between the two pipes, they never had any more troubles.