SAN DIEGO CITY CODES RE WATER HEATER REPLACEMENT: rebrand.ly/waterheater

2010 Residential Water Heater Replacement Check List  LINK TO PDF VERSION OF BELOW

The intent of this check list is to provide installers a general reference for the enforcement of code 
requirements in the Greater San Diego Area. This checklist is for storage type water heaters only. This 
checklist does not cover all the code requirements found in the plumbing code. Be sure to check with 
local jurisdictions for adopted local amendments and code updates. 

Unless otherwise noted, the following code excerpts apply to new and replacement water heaters. It is important to note that an existing water heater is a water heater that was previously inspected and approved
by the Authority Having Jurisdiction. 

It shall be unlawful for any person to install, remove, or replace or cause to be installed, removed, 
or replaced any water heater without first obtaining a permit from the Authority Having Jurisdiction to
do so. (2010 CPC 503) 
The installing agency shall leave the manufacturer's installation, operating, and maintenance instructions in a location on the premises where they will be readily available for reference and guidance
for the Authority Having Jurisdiction, service personnel, and the owner or operator. 
(2010 CPC 508.26) 
Plumbing systems shall be installed in a manner conforming to this code, applicable standards, 
and the manufacturer’s installation instructions. In instances where the code, applicable standards,
or the manufacturer’s instructions conflict, the more stringent provisions shall prevail. 
(2010 CPC 310.4) 
The installation of temperature, pressure and vacuum relief devices or combinations thereof, and 
automatic gas shutoff devices, shall be installed in accordance with the terms of their listings and 
the manufacturer’s instructions. (2010 CPC 505.6) 
All new and replacement water heaters must meet minimum energy efficiency requirements and 
be on the most current list of approved appliances on the California Energy Commission website. 
http://www.appliances.energy.ca.gov/ 

Any water system provided with a check valve, backflow preventer, or any other normally closed 
device that prevents dissipation of building pressure back into the water main shall be provided 
with an approved, listed, and adequately sized expansion tank or other approved device having a 
similar function to control thermal expansion. (2010 CPC 608.3) Commentary: A check valve or 
other normally closed device will create a closed system which requires an expansion 
tank. Inspectors will require an expansion tank when a check valve is visible. A qualified 
plumber may further determine that the system is closed at non-visible locations through 
the use of tools and test equipment. Items such as water meters and water softeners and 
regulators sometimes have built-in check valves. 
An approved expansion tank shall be installed in the cold water distribution piping downstream of 
each pressure regulator to prevent excessive pressure from developing due to thermal expansion 
and to maintain the pressure setting of the regulator. (2010 CPC 608.2) Commentary: This is a 
new requirement. Expansion tanks will be required on new construction homes that have a 
water pressure regulating device. Expansion tanks must be properly sized and 
pressurized in accordance to the manufacturer’s instructions. See Footnote #1.Pressure in 
water systems is considered excessive when the pressure exceeds 80 psi. Damage can 
occur to water heaters and other components in the water system when they are subjected 
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to excessive water pressure. When water is heated, it causes expansion and increased 
pressures in both the hot and cold water piping system. In an open system, water can only 
push back into the street provided that the street pressure is less than the expanding 
water pressure. A properly sized and installed expansion tank protects the water heater 
and other water system components from excessive water pressure within the range of 
the regulator setting and the relief valve setting. Most warranties for plumbing fixtures and 
water heaters become null and void when the products are subjected to excessive 
pressure. 

A shutoff valve shall not be placed between the relief valve and the water heater or on discharge 
pipes between such valves and the atmosphere. The hourly Btu discharge capacity of the device 
shall be not less than the input rating of the water heater. (2010 CPC 505.6) 
Relief valves located inside a building shall be provided with a drain, not smaller than the relief 
valve outlet, of galvanized steel, hard-drawn copper piping and fittings, CPVC or listed relief valve 
drain tube with fittings that will not reduce the internal bore of the pipe or tubing (straight lengths 
as opposed to coils) and shall extend from the valve to the outside of the building, with the end of 
the pipe not more than two feet nor less than six inches above ground or the flood level of the 
area receiving the discharge and pointing downward. Such drains shall be permitted to terminate 
at other approved locations. Relief valve drains shall not terminate in a building’s crawl space. No 
part of such drain pipe shall be trapped or subject to freezing. The terminal end of the drain pipe 
shall not be threaded.(2010 CPC 608.5) 
Discharge from a relief valve into a water heater pan shall be prohibited. (2010 CPC 508.5) 
Residential water heaters shall be sized in accordance with table 5-1. (2010 CPC table 5-1) 
Water heaters installed in residential garages shall be installed so that burners and burner-
ignition devices are located not less than 18” above the floor unless listed as flammable vapor 
ignition resistant. (2010 CPC 508.14) Commentary: Since July 1st 2003, water heater 
manufacturers have been required to incorporate Flammable Vapor Ignition Resistant 
(FVIR) Technology into 30, 40 and 50 gallon gas water heaters that are sold in the United 
States. Water heaters with FVIR technology may be installed on the floor of a residential 
garage. Electric water heaters do not have mandated FVIR technology and may cause a 
small spark when heating. Electric water heaters should be placed on a stand unless 
documentation is provided by the installer/manufacturer that verifies FIVR construction. 
Water heaters shall be located or protected so they are not subject to physical damage by a 
moving vehicle. (2010 CPC 508.14.2) Commentary: An acceptable bollard design consists of 
2 ”or larger schedule 40 pipe, embedded 3 feet into the ground, encased in a 12” diameter 
footing and filled with concrete. Flanged bollards, fastened with bolts to a concrete floor, 
wheel stops and elevating the water heater may also be acceptable when approved by the 
Authority Having Jurisdiction. 
Water heaters shall be anchored or strapped to resist horizontal displacement due to earthquake 
motion. Strapping shall be at points within the upper one third and lower one-third of its vertical 
dimensions. At the lower point, a minimum distance of 4” inches shall be maintained above the 
controls with the strapping. (2010 CPC 508.2) 
 
A water heater supported from the ground shall rest on level concrete or other approved base 
extending not less than 3” above the adjoining ground level. (2010 CPC 508.3) 


Water heaters installed in attics must have adequate support for the weight of the water heater. 
See the 2010 CRC section R301.4, the actual weights of materials and construction shall be used 
for determining dead load with consideration for the dead load of fixed service equipment. It is 
recommended to check with the local building department for permit history and/or submittal 
requirements. 

When a water heater is located in an attic, attic-ceiling assembly, floor-ceiling assembly, or floorsubfloor 
assembly where damage results from a leaking water heater, a watertight pan of 
corrosion-resistant materials shall be installed beneath the water heater with not less than 3/4” 
diameter drain to an approved location. (2010 CPC 508.4) 
An attic in which an appliance is installed shall be accessible through an opening and 
passageway not less than as large as the largest component of the appliance and not less than 
22” x 30” (2010 CPC 509.4.2) 
Where the height of the passageway is less than 6 feet, the distance from the passageway 
access to the appliance shall not exceed 20 measured along the centerline of the passageway. 
(2010 CPC 509.4.1) 
The passageway shall be unobstructed and shall have solid flooring not less than 24” inches wide 
from the entrance opening to the appliance. (2010 CPC 509.4.3) 
A level working platform not less than 30” x 30” shall be provided in front of the service side of the 
appliance. (2010 CPC 509.4.4) 
A permanent 120-volt receptacle outlet and a lighting fixture shall be installed near the appliance. 
The switch controlling the lighting fixture shall be located at the entrance to the passageway. 
2010 CPC 509.4.5) 
The clearances shall not be such as to interfere with combustion air, draft hood clearance and 
relief, and accessibility for servicing. Listed water heaters shall be installed in accordance with 
their listings and the manufacturer’s instructions. (2010 CPC 505.3.1, 510.6.1.1) 
Flexible gas supplies. Listed flexible gas connectors shall be in compliance with CSA Z21.24, 
Standard for Connectors for Gas Appliances. The connector shall be used in accordance with the 
terms of their listing that are completely in the same room as the appliance. (2010 CPC 1212.1.3) 
Note: CSA certifies gas connectors up to 6’ (72”). Joining two or more connectors is not 
permitted by product standards. Flexible gas connectors can only be used above ground. 
The gas supply outlet must be in the same room as the appliance and the connector must 
not be concealed within or run through any wall, floor or partition. According to the 
requirements of the CSA specification that governs appliance gas connectors, the 
connector and fittings are design for use only on the original installation and are not to be 
reused for another appliance or at another location. 

Water heaters connected to a piping system shall have an accessible, approved manual shutoff valve 
with a non-displaceable valve member, or a listed gas convenience outlet installed within six (6) feet 
(1.8 m) of the appliance it serves. Where a connector is used, the valve shall be installed upstream of 
the connector. 2010 CPC 1215 
1212.7 Sediment Trap. Where a sediment trap is not incorporated as a part of the gas utilization 
appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close 
to the inlet of the appliance as practical at the time of appliance installation. The sediment trap 
shall be either a tee fitting with a capped nipple in the bottom outlet, as illustrated in Figure 12-1, 
or other device recognized as an effective sediment trap. (2010 CPC 1212.7) Commentary: A 


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sediment trap is required at water heaters. See attached Figure 12-1 for an acceptable 
sediment trap design. Sediment traps help prevent debris in the gas system from clogging 
the inlet screen on the gas control valve and help prevent debris from damaging the 
control valve. Most warranties are null and void if it is determined that debris caused 
damage to the gas control valve. 

When an additional or replacement appliance is installed or an appliance is converted to gas from 
another fuel, the location in which the appliance is to be operated shall be checked to verify the 
following: (1) Air for combustion and ventilation is provided where required, in accordance with 
the provisions of Section 507.0. Where existing facilities are not adequate, they shall be upgraded 
to Section 507.0 specifications. (2) The installation components and appliances meet the 
clearances to combustible material. (3) It shall be determined that the installation and operation of 
the additional or replacement appliance does not render the remaining appliance unsafe for 
continued operation. (2010 CPC 508.6, 508.6.1) 
Joints between sections of connector piping and connections to flue collars or draft hood outlets 
shall be fastened in accordance with one of the following methods (1) By sheet metal screws. (2) 
Vent connectors of listed vent material shall be assembled and connected to flue collars or draft 
hood outlets in accordance with the manufacturer’s instructions. (3) Other approved means. 
Commentary: The vent connector must be fastened to the draft hood, at each joint and to 
the first B-vent fitting. Three sheet metal screws or more are typically needed to hold the 
joint rigidly in place. 

Type B vents shall extend in a generally vertical direction with offsets not exceeding 45 degrees, 
except that a vent system having not more than one 60 degree offset shall be permitted. Any 
angle greater than 45 degrees from the vertical is considered horizontal. The total horizontal 
distance of a vent plus the horizontal vent connector serving draft-hood-equipped appliances 
shall not exceed 75 percent of the vertical height of the vent. (2010 CPC 510.6.1.1) 
The maximum horizontal length of a single-wall connector shall be 75 percent of the height of the 
chimney or vent except for engineered systems. (2010 CPC 510.10.9.2) 
The maximum horizontal length of a Type B double-wall connector shall be 100 percent of the 
height of the chimney or vent, except for engineered systems. The maximum length of an 
individual connector for a chimney or vent system serving multiple appliances, from the appliance 
outlet to the junction with the common vent or another connector shall be 100 percent of the 
height of the chimney or vent. (2010 CPC 510.10.9.3) 
A gas vent shall terminate in accordance with one of the following: (1) Above the roof surface with 
a listed cap or listed roof assembly. Gas vents 12” in size or smaller with listed caps shall be 
permitted to be terminated in accordance with Figure 5-2, provided they are at least eight 8’ from 
a vertical wall or similar obstruction. (2010 CPC 510.6.2) See the attached figure 5-2. 
A Type B or a Type L gas vent shall terminate at least five 5’ in vertical height above the highest 
connected appliance draft hood or flue collar. (2010 CPC 510.6.2.1) 
Electric water heaters are required to have a disconnect within sight of the water heater or have a 
breaker that is of a locking type. (See 2010 CEC 422.30 and 422.31B) 



Sediment trap diagram 2010 CPC Figure 12-1  below




Footnotes #1 See the following web pages for more information. 

http://www.aohomeinspection.com/pdf/Thermal-expansion-control.pdf 
http://www.hotwater.com/lit/bulletin/bulletin45.pdf 
http://www.watts.com/pages/learnAbout/thermalExpansion.asp?catId=64#generalinfo 

#2 See the following websites for more information. 

http://media.wattswater.com/IOM-D-RES-1132.pdf