Water Heater Replacement in Ontario, CA

Do I need a permit to replace a water heater in Ontario?

Plan on one. The City of Ontario Building Department issues building permits and accepts applications electronically through its Citizen Portal Access website; the department can be reached at (909) 395-2023. Usually the installing plumber files the permit and books the inspection, where items such as seismic straps, venting, the gas connection and the relief valve line are checked. Ask that the permit be written into the quote.

How hard is Ontario's water on a new tank?

Ontario Municipal Utilities Company delivers drinking water citywide from several sources, and its 2025 water quality report lists hardness for each. City groundwater averages 124 mg/L (range 82 to 150), imported water averages 91 mg/L, and purchased groundwater from the desalter and Jurupa Community Services District wells averages 137 to 177 mg/L. That is moderately hard to hard water, enough to build scale in a tank over the years, so annual flushing is sensible. The report also shows a total chlorine residual that includes chloramines, which can wear rubber washers and gaskets faster than plain chlorine.

Should the replacement be the same kind of heater?

Not necessarily. City-stats.com puts the median year built in Ontario at about 1980, so many older homes have a gas tank in the garage or a closet, while homes in newer areas such as Ontario Ranch are much more recent. A like-for-like gas tank is the fastest swap. A tankless unit or a heat pump water heater can lower operating costs for some households, but each adds work: a larger gas line and new venting for tankless, or a dedicated circuit and condensate drain for a heat pump. A plumber can tell you what your space and panel will support, and price more than one option so you can compare.

One Ontario safety note

SoCalGas provides natural gas in Ontario. If you notice a gas smell near the water heater, get everyone outside first, then call 911 and SoCalGas at 1-800-427-2200. Don't flip switches or try to relight anything on the way out. Once the house is safe again, a plumber can check the gas connector, shutoff valve and venting on the old heater before the new one goes in.