WATER HEATERS

 

Water heater as monolith.

If you’re like most people, you’re unlikely to go out looking for a water heater until your existing one fails, leaving little time to find an efficient water heater that meets your design and price point needs. There are a lot of technologies available, and the best water heaters are also the hardest to find and the most expensive to purchase. So it pays to think about your options now!

Is it too late? Yes, it is, otherwise you wouldn’t be even reading this. We all forget water heaters exist until they go bad. Do not worry. We can help you. Give us a call so we can figure out all the details for you.

Rules To Remember:

  • Seismic Straps – Water heaters 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. (CPC 508.2)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 structure or the slab. Additional blocking at the water heater may be required to resist horizontal displacement.
  • Venting – All vent piping used in residential occupancies shall be double-wall metal pipe (single-wall metal pipe is not allowed). The vent and the water heater must maintain clearance from combustible materials such as wall framing or roofing; the clearance requirement is based on the manufacturer’s installation requirements, but is typically 1″ minimum. The vent shall terminate a minimum 1’ above the roof through flashing at the roof and terminate in a listed and approved vent cap. Venting shall extend in a generally vertical direction with offsets not exceeding 45, except one 60 offset is permitted. Vents may require additional supports depending on the material and design. (CPC 510.6.1.1, 510.7.4.1)
  • Pressure-Temperature Relief Valve – All water heaters have a pressure/temperature (P/T) relief valve. The valve shall be drained to the exterior and terminate toward the ground maintaining 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. 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. 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. (CPC 608.5)
  • Located in a Garage – Water heaters located in a garage must be elevated so the pilot light and controls are at least 18″ above the garage floor surface (unless the unit is listed as flammable vapor ignition resistant). If subject to damage, adequate barriers must be installed. (CPC 508.14)
  • Located in an Attic or Furred Space – If located in an attic or furred space (i.e. closet) where leaking could cause damage to underlying wood framing, 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. (CPC 508.4)
  • Located in a Bedroom, Bathroom, or Closet – Shall be permitted when provided with a listed self-closing, gasketed door and all combustion air shall be obtained from outdoors. Closets shall not be used for any other purpose. (CPC 505.1 , 505.1.1, 505.1.2)
  • Located in Attic – shall be accessible through an opening and passageway at least large as the largest component of the appliance, and not less than 22” by 30”. Where the height of passageway is less than 6 feet the distance from the passageway access to appliance shall not exceed 20 feet measured along the centerline of the passageway. The passageway shall be unobstructed and shall have solid flooring not less than 24 inches. A level working platform not less than 30 inches by 30 inches shall be provided in front of the service side of the appliance. A permanent 120-volt receptacle outlet and lighting fixture shall be installed near the appliance. The switch controlling the lighting fixture shall be located at the entrance to the passageway. (CPC 509.4)
  • Combustion Air – Combustion air must be maintained per the California Plumbing Code. When the appliance is located in an unconfined space (e.g. garage) the combustion air can be used from that area. When located in a closet, combustion air must be provided at a minimum of two openings (one at the top and one at the bottom) sized at 100 square inches each. (CPC 507)
  • Sediment Trap – A sediment trap shall be installed on the gas line downstream of the appliance shut-off valve and as close to inlet of the equipment as practical. (CPC 1212.7)
  • Tankless Water Heaters – Tank less water heaters shall be listed by an approved testing agency (UL, UPC, etc.) and be installed in accordance with the manufacturer’s requirements. Category II stainless venting material and larger gas supply lines may be required based on the manufacturer’s specifications/recommendations. (CPC 508.26)Note: PG&E requires a minimum horizontal clearance of 36 inches between the gas meter and a tankless water heater when located on the same wall.