What Does a Tankless Water Heater Cost in Norwalk, CA?

Converting a storage tank water heater to a tankless unit in Norwalk is $3,295 when the tank being replaced is 40 gallons and $3,695 when it is 50 gallons, at our book price, installed. Those two prices are for the Noritz EZTR40 and EZTR50, the only tankless models built to use the existing water heater hookups, which is what makes a book price possible at all. Any other brand or model is quoted on site. Below is what the conversion price includes, what is quoted separately, and what the Norwalk permit and water add to the picture.

The conversion price covers removing the storage tank, installing the Noritz EZTR40 or EZTR50 on the existing hookups, new hot and cold water supply lines, a new gas supply line, and isolation valves so the unit can be flushed without shutting the house down. Hauling the old tank away is $95. A drain pan is $75 and a gas sediment trap is $225 where the inspector calls for them. The permit is separate and is covered below. The full book is on our pricing page.

Every tankless brand other than the Noritz EZTR line needs its own gas line sizing, venting and mounting, and that is decided by the house, not the catalog: how far the gas run is, what size the line is, where the vent can exit, and whether the unit is moving. So a Navien, Rinnai, Takagi or Rheem installation is evaluated on site and quoted in writing before any work starts. A venting upgrade from single wall to double wall is $250 to $450 on a tank job and is one of the items we check on a conversion. Relocating the heater, or putting one in a home that never had one, is quoted the same way. If you are weighing a tank against tankless, the tank replacement price is on our installation page and in what a water heater replacement costs in Norwalk.

The City of Norwalk Building & Safety Division requires a plumbing permit and an inspection for a water heater replacement; the office is at 12700 Norwalk Boulevard and can be reached at (562) 929-5733. We pull the permit and meet the inspector for a $295 administrative fee plus the city's own permit fee, which is passed through at cost as its own line on the quote. Norwalk's published fee for a water heater change-out is $196 (a flat residential water heater change-out permit, before the city's 5% technology fee), so the permit line comes to $295 + $196 = $491. You can decline and pull the permit yourself, but if the inspector then calls for a code correction, that work is charged at book price.

The Norwalk Municipal Water System measured its groundwater supply at 15 grains per gallon in 2025 (256 mg/L as calcium carbonate, ranging from 166 to 482 mg/L); Golden State Water measured its Norwalk system at 18 grains per gallon in 2025 (310 mg/L as calcium carbonate, ranging from 137 to 505 mg/L); Liberty Utilities measured its Bellflower-Norwalk system at 14.8 grains per gallon in 2025 (255 mg/L as calcium carbonate), against the 10.5 grains that classifies water as very hard. A tankless heat exchanger has narrow passages, and at that hardness the manufacturers call for a descale flush every year; skipping it is how a tankless unit ends up throwing error codes a few years in. The yearly descale is $259, or it is included in the $199 per year tankless membership along with free diagnostics when a repair is needed. If the unit does fault, the tankless diagnostic is $299, includes the flush, and is waived if we repair or replace it.

Norwalk was built largely in the 1950s tract-home boom, compact homes around the Civic Center, North Norwalk and the Studebaker corridor. Those original layouts put the water heater in a compact garage alcove or a tight closet, often still with dated gas connections and no expansion tank or seismic strapping. A tankless unit hangs on the wall where the tank stood and reuses the tank's flue path when it is a Noritz EZTR on a straight swap, which is what keeps the conversion at book price. A venting upgrade from single wall to double wall is $250 to $450 where the inspector calls for it, a gas sediment trap is $225, and a drain pan is $75. A closet installation inside the house, or a second-floor unit, carries a $249 surcharge over the book price; moving the unit somewhere else is quoted on site.

Book prices apply during normal business hours, Monday through Friday, 8 AM to 5 PM; pricing outside those hours or in an emergency is subject to change. Conversions are scheduled at least 24 hours ahead. Prices are current as of September 2026 and subject to change, and the quote is in writing before any work starts. A conversion is the job most people finance, and checking your options takes a few minutes. We dispatch from Pico Rivera, about 15 minutes from most Norwalk addresses; call 833-927-3356 or send us the details.