Water guides · Updated November 2, 2026

Water heater replacement in Naples, Fort Myers, and Bonita Springs: tank vs. tankless, hard water, and signs it is time

Short answer: replace a water heater when the tank itself is leaking, the hot water comes out rusty, or the unit is near the end of its normal life and repairs keep adding up. Department of Energy guidance puts tank heaters at about 10 to 15 years and tankless units at up to 20, and local water quality is one of the biggest reasons a heater lands at the short or long end. Tank vs. tankless comes down to your fuel, space, venting, electrical service, and how the house uses hot water. Hard water builds scale, which matters most for tankless, so know your hardness before you choose.

Most water heater calls in Naples, Fort Myers, and Bonita Springs start the same way: a cold shower, a puddle by the closet, or a rumble from the garage. This guide covers how to tell repair from replacement, how hard water and softened water each affect a heater, and how to decide between tank and tankless. Our water heater service page covers what we install and repair.

What are the signs it is time to replace a water heater?

• Water coming from the tank itself. A leak at the supply connections, the drain valve, or the temperature-and-pressure relief valve can often be repaired. A leak from the tank body usually cannot.
• Rust-colored hot water, especially if the cold water is clear.
• Rumbling or popping from the tank, which often points to sediment built up on the bottom.
• Less hot water than you used to get, or water that turns lukewarm quickly.
• Age. If the heater is approaching the typical life range below and needs another repair, replacing it may be the better use of the money.

We find the source before we tell you the tank is done. A failed valve or fitting is a repair, not a replacement.

How long does a water heater last?

The DOE Building America guide to tankless water heaters says tankless water heaters are generally considered to last up to 20 years, compared with 10 to 15 years for tank-type heaters. A Department of Energy report by Pacific Northwest National Laboratory puts the overall range at 8 to 20 years, depending on heater type, water quality, and maintenance, and names local water quality as one of the factors that matters most (DOE/PNNL report on water quality and water heaters).

How does hard water shorten water heater life?

Hard water carries calcium and magnesium, and heating it leaves scale behind. According to the DOE Building America guide to tankless water heaters:

• In a tank heater, scale builds up at the bottom of the tank and has much less effect on flow and performance than in a tankless unit.
• In a tankless heater, scale builds up in the heat exchanger, where it can restrict water flow and shorten the life of the unit.
• Tankless units should be flushed on the manufacturer’s schedule, which can range from twice a year to once every three years.
• Some manufacturers may require a water softener when hardness runs above roughly 8 to 14 grains per gallon (136 to 239 ppm).

Manufacturers put this in writing. Rinnai, for example, tells owners to flush its tankless heaters at least once a year (Rinnai flushing instructions), and its residential warranty excludes damage from improper maintenance such as scale build-up, and damage caused by poor water quality (Rinnai SENSEI residential limited warranty). For tank heaters, the DOE/PNNL report lists draining the tank every year to remove sediment as a mitigation for hard water (DOE/PNNL report on water quality and water heaters).

Can a water softener hurt a water heater?

It changes the maintenance, not the decision. The same DOE/PNNL report notes that softened water corrodes the anode rod faster, which can shorten the life of a steel tank if the anode is not maintained. For soft water it recommends inspecting the anode every 1 to 2 years and replacing it as needed, and it cites an A.O. Smith manual that recommends an anode inspection after 3 years and every year after that (DOE/PNNL report on water quality and water heaters).

In practice, if you have a water softener and a tank heater, put the anode rod on the maintenance list. If you have hard water and a tankless heater, put flushing on the list, and consider whether softening makes sense based on a test.

How hard is the water in Naples, Fort Myers, and Bonita Springs?

It depends on your supplier, and well water can be very different from city water. Here is what the utilities publish:

• City of Naples: delivered hardness averaged 67 mg/L in 2024 (about 3.9 grains per gallon), which the city’s report classifies as soft to moderately hard (City of Naples 2024 Annual Water Quality Report). See our Naples page for more local details.
• City of Fort Myers: treats brackish Floridan Aquifer water with reverse osmosis (City of Fort Myers 2025 Annual Water Quality Report), and its water plant FAQ lists hardness at approximately 30 ppm, or 1.8 grains per gallon (City of Fort Myers water plant FAQ). See our Fort Myers page.
• Bonita Springs Utilities: blends lime-softened water with reverse-osmosis water (Bonita Springs Utilities 2025 water quality report).
• Private wells in areas such as Golden Gate Estates and parts of Bonita Springs and Estero are not covered by any utility report, so the number has to come from a test.

Your utility’s annual water quality report lists hardness if it was measured, and our free water test checks it at your tap.

Tank or tankless: which fits your home?

Neither one is right for every house. Here is how they compare on the points that come up most:

• Life span: about 10 to 15 years for tank heaters, and up to 20 years for tankless, per the DOE guide above.
• Sizing: a tank is sized by storage. A tankless unit is sized by flow, in gallons per minute, and by the temperature of the incoming water (DOE Building America guide to tankless water heaters).
• Hard water: scale settles in the bottom of a tank, which needs regular draining. In a tankless heater it coats the heat exchanger, which needs regular flushing and may call for softening.
• Electrical service: electric tankless heaters draw a lot of current, typically 50 to 200 amps depending on the size of the unit, according to the DOE guide (DOE Building America guide to tankless water heaters). Check that your panel can handle it before you choose one.
• Gas and venting: gas units, tank or tankless, need the right gas supply and venting for the model.
• Space: tankless units mount on the wall, which can free up a closet or garage corner.

We also work on heat pump and solar-assisted water heaters when that is what is already in the house or what the home needs. The recommendation should come from the house, not from whatever is easiest to hang on the wall.

Do you need a permit to replace a water heater?

Often, and the rules vary by jurisdiction. In Collier County, a water heater replacement permit can be self-issued in simple cases. Changing the type (for example, tank to tankless), the size, or the location sends it through standard permitting and plan review (Collier County water heater replacement permit (PRWH)). Lee County, the City of Fort Myers, and the City of Bonita Springs set their own requirements. We confirm what your address needs before the work starts.

What happens at a free consultation

We look at the heater you have, the connections and valves, and the gas, electric, and venting setup. We ask how the house uses hot water, then explain repair versus replacement and tank versus tankless in plain language. If hardness may be part of the problem, we can do a free water test on the same visit, so you know your number before deciding on a tankless unit or a softener.

Related guides: hard water in Southwest Florida: what to test for, why your water smells like rotten eggs (including hot water only), and chloramine vs. chlorine in Lee County water.

Book a free consultation or a free in-home water test: call 239-376-0640 or send a request. The Bonita Springs shop serves Naples, Fort Myers, and Bonita Springs. Waterbird SWFL serves Lee, Collier, and Charlotte counties, from Marco Island to Port Charlotte. Florida Certified Plumbing Contractor, Lic. #CFC1433714.