Function

• Both electric and gas-powered water heaters are tall cylindrical appliances which warm and store an amount of water, typically 30 gallons. These major appliances are intended to run without maintenance for between 10 and 15 years, according tot he U.S. Department of Energy. Of course, this lifespan is dependent upon the water source, regular maintenance, and several other factors.

  There are new “tankless” water heaters that do not store water, but instead use a series of pipes surrounded by heating elements. Though popular in Europe for decades, tankless water heaters are relatively new in the United States. Though significantly more expensive than traditional water heaters, a tankless water heater can last up to 30 years.

Time Frame

• During the average 10 year lifespan of a water heater, the minerals that have dissolved into the water source can be deposited on the inside of the tank. Calcium and lime, in particular, react when heated and bind to the inside of the tank. The result is a tank that slowly loses capacity as well as having to use more energy to heat the same volume of water because of the rock-like nature of these mineral deposits. Untreated “hard water,” that is water with a high lime or calcium content, can reduce the lifespan of a water heater by two or more years. Additionally, some sources of water, such as springs and wells, can pull up sediment and deposit sand and mud inside the water heater, reducing its effectiveness even more quickly that minerals. A water heater attached to one of these sources should be drained and flushed about once a year.

Size

• The size of the water heater may have an effect on its life expectancy as well. If a water heater is too small for the household and is constantly heating large volumes of water, this may damage the glass lining of the water heater, wear out the heating elements faster, or cause electrical problems. Water heaters that are too small will need to be replaces at least two years earlier than they normally would in an appropriate setting.

  Conversely, a water heater that is too large for a household will need to work harder to maintain the volume of water it already has stored, which may in turn cause higher electrical or gas bills though it will not necessarily diminish its life span.

Benefits

• No matter what kind of water heater used, regular maintenance will increase its life span. A certified heating and plumbing specialist can detect potential problems, recommend filtration systems (if necessary) and take other measures to prevent a premature breakdown of the water heater. The manufacturer of your water heater may have specific requirements for routine maintenance, so consult the owner’s manual before calling a plumber. Regular maintenance can extend the life of your water heater by up to five years.

Considerations

• Though the average life span may be more than a decade or so, replacing your water heater about every 10 to 15 years not only ensures smooth heating of water, but also saves energy and money. According to the Department of Energy (DoE), heating water accounts for 13% of the average utility bill. In order to maximize savings, the DoE recommends investing in a natural gas or tankless water heater or investing in “green” water heating technology such as a solar water heater or a heat pump water heater instead.

  CALIFORNIA INSTALLATION REQUIREMENTS:

  GENERAL

  A PLUMBING PERMIT IS REQUIRED FOR ALL WATER HEATER INSTALLATIONS

  AND REPLACEMENTS. A FINAL INSPECTION IS REQUIRED AFTER ALL WORK

  HAS BEEN COMPLETED. THE FOLLOWING ARE WATER HEATER INSTALLATION

  REQUIREMENTS FROM THE 2010 CALIFORNIA CODES.

  SEISMIC BRACING [CPCSECTION 508.2]

  Water heaters up to 75 gallons require two seismic straps; one located within the top

  1/3 of the water heater unit and one at the bottom 1/3. The bottom strap must be

  located at least 4” away from the water heater controls. A minimum of three seismic

  straps are required for water heaters greater than 75 gallons. There are a number of

  seismic strap kits that are available commercially, however, metal plumbers tape can be

  used if it completely encircles the water heater and is then attached to a structural

  framing member at each end. Any platform supporting the water heater must be

  secured to the structures or the slab.

  VENTING [CPC SECTION 510.6, CMC SECTION 802.6.2]

  All single wall and single wall to double wall joints shall be secured with a minimum of

  three sheet metal screws, rivets or similar positive connections. Single wall vent are

  prohibited in residential occupancies per CBC 510.7.4.1. The vent and the water heater

  must maintain clearance form combustible materials such as wall framing or roofing.

  Generally the minimum distance is 6” for single wall and 1” for double wall and the water

  heater check the manufactures listing on the materials. The vent shall terminate a

  minimum 12” above the roof through flashing at the roof and terminate in a listed and

  approved vent cap. Vents may require additional supports depending on the material

  and design.

  PRESSURE/TEMPERATURE VALVE [SECTION 505.6, 608.5]

  All water heaters have a pressure /temperature (P/T) valve. The valve shall be drained

  to the exterior and terminate toward the ground maintain between 6” and 24” of

  clearance from the ground and pointing downward. The diameter of the valve opening

  (generally 3/4”) must be maintained to the termination of the drain. Check the

  manufacturer’s requirements. When approved by the Chief Building Official, such drain

  may terminate at other locations (i.e., laundry tub, floor sink, or floor drain). No part of

  such drain shall be trapped and the terminal end of the drain shall not be threaded.

  WATER HEATER INSTALLATION AND REPLACEMENT

  COMMUNITY DEVELOPMENT DEPARTMENT • BUILDING DIVISION

  ALBERT SALVADOR, P.E., C.B.O., BUILDING OFFICIAL

  10300 TORRE AVENUE • CUPERTINO, CA 95014-3255

  (408) 777-3228 • FAX (408) 777-3333 • building@cupertino.org

  WaterHeater.doc revised 02/08/12

  LOCATED IN BEDROOMS AND BATHROOMS [CPC SECTION 505]

  Water heater installations in bedrooms and bathrooms shall comply with the provisions

  of CPC Section 505.

  LOCATED IN A GARAGE [CPC SECTION 508.14]

  Water heaters located in a garage must be elevated so the pilot light and controls are at

  least 18” above the garage floor surface. Appliances shall be located or protected so it

  is not subject to physical damage by a moving vehicle.

  LOCATED IN AN ATTIC OR UNDER-FLOOR SPACES [CPC SECTION 508.4, 509.4,

  CMC SECTION 904.11]

  Water heaters located in an attic or under-floor space shall be accessible through an

  opening not less than the largest component of the appliance, and not less than

  22”x30”. Passageway to the appliance shall not exceed 20’ where the height of the

  passageway is less than 6’. Passageway shall be unobstructed and shall have solid

  flooring not less than 24” with a work platform not less than 30”x30” installed with a

  receptacle outlet and light fixture.

  The water heater must be set in a pan constructed of water tight corrosion resistant

  material. The pan must be fitted with a minimum 3/4” drain that drains to an approved

  location. The P/T line is not allowed to terminate at this pan or be connected to it.

  COMUBUSTION AIR MUST BE MAINTAINED [CPC SECTION 507]

  Combustion air must be maintained per the California Plumbing Code. One final

  inspection is required after all work has been completed.

  INSULATION [2010 CALIFORNIA ENERGY CODE SECTION 105 (j) 2]

  The first 5’ of the hot and cold water pipes connected to the water heater shall be

  insulated with foam plastic pipe insulation. The insulation shall be installed so that it is at

  least 6” from the sheet metal flue pipe.

  BONDING [CMC SECTION 1312.13]

  Metallic water and gas pipes within a residence are connected together with electrical

  bonding wires and then grounded to prevent shock hazards should an energized

  electrical wire come in contact with the pipe. The bonding will typically take place at the

  water pipe of the water heater.