Tank or Tankless in Marion? What Hard Water Does to Each One

Oct 30, 2026

When a water heater gives out in Marion, the first question is usually whether to put in another tank or go tankless. Both work fine here. The thing that decides how long either one lasts is your water, and in Grant County that depends a lot on whether you’re on city water or a well.

City water vs. well water in Marion

Marion Utilities pulls its water from wells in the Teays River Valley aquifer, and its 2026 water quality report says the groundwater is softened and filtered at the plant before it goes out to homes. So if you’re on city water inside Marion, your water is already treated, and plenty of homes in town don’t have a softener at all.

Out in the county it’s a different story. Homes on private wells around Jonesboro, Fairmount, Swayzee, Sweetser, Converse or out toward Van Buren get the water straight out of the ground, and most of it is hard. Iron is common too. You can spot it on the fixtures: white crust on the faucet aerator, a showerhead that sprays sideways, orange stains in the toilet.

If you don’t know your number, test it. A cheap test strip from the hardware store gets you close, and we can test it when we’re out.

What hard water does to a tank water heater

In a regular tank, the minerals settle to the bottom as the water heats up. Over the years that sediment builds a layer between the burner (or the lower element on an electric tank) and the water. You’ll hear it as popping or rumbling when the heater runs. The heater works harder, the bottom of the tank runs hotter, and the steel wears out sooner.

A tank on hard well water that never gets flushed can be done in 8 or 9 years. The same tank on softened water, flushed every year, often lasts well past 12. The two things that help most are a yearly flush and checking the anode rod every few years. Our water heater maintenance visit covers both.

What hard water does to a tankless water heater

A tankless unit heats water as it flows through a small heat exchanger. There’s no tank for sediment to sit in, but scale builds up inside those narrow passages instead. When that happens, you get water that won’t stay hot, error codes, and a unit that shuts itself off to protect the exchanger.

Tankless heaters need descaling: running a vinegar or descaler solution through the unit with a small pump. On softened city water, once a year is usually plenty. On hard well water with no softener, some units need it twice a year, and skipping it is the most common reason we see tankless heaters fail early. Most manufacturers also expect the water to be within a certain hardness range to keep the warranty in force, so read that part before you buy.

So which one is right for your house?

A tank water heater makes sense if:

You want the lowest price up front and a simple swap in the same spot
Your household uses hot water in big bursts, like back-to-back showers in the morning
You’re on a hard well and don’t plan to add a softener

A tankless water heater makes sense if:

You want hot water that doesn’t run out, especially with a big tub or a large family
You need the floor space in a small utility room or basement
You’re on softened city water, or you have or will add a water softener
You plan to stay in the house long enough for the longer life and lower gas use to pay off

A few practical things in older Marion homes: a gas tankless unit usually needs a larger gas line than the old tank did, and it vents through the wall with PVC or stainless pipe instead of up the old chimney. If the old water heater shared a chimney with the furnace, that venting may need to change too. We check all of that before we give you a price, so the quote you get is the real one.

If you’re on a well, think about the softener first

For a lot of homes in the county, the best money spent is on a water softener before or with the new water heater. Softer water protects either kind of heater, along with your faucets, dishwasher and washing machine. If there’s iron or sulfur smell in the water, we can look at water filtration too.

Frequently asked questions

Is Marion city water hard?

Marion Utilities says in its 2026 water quality report that the groundwater is softened and filtered at the plant before it reaches homes. Private wells in the county are a different story. Most are hard, and many have iron, so test your water if you’re on a well.

How long does a tank water heater last on hard water?

On hard well water with no softener and no flushing, a tank can wear out in 8 or 9 years. On softened water with a yearly flush and an anode check every few years, many last 12 years or more.

Do tankless water heaters work with well water?

Yes, but hard well water builds scale in the heat exchanger. Plan on descaling once or twice a year, or add a water softener. Check the manufacturer’s hardness limits so the warranty stays valid.

How often should a tankless water heater be descaled?

Once a year on softened city water is usually enough. On hard well water with no softener, some units need it every six months.

Can I put a tankless water heater where my old tank was?

Usually, but it may need a bigger gas line, new venting through the wall instead of the chimney, and a nearby outlet. We check those before quoting so there are no surprises on install day.

Talk it over with a local plumber

Summers Plumbing Heating & Cooling has been serving Marion and the surrounding area since 1969 from our shop at 614 E 4th St. We install both kinds and will tell you which fits your house and your water. See our tankless water heater installation and water heater installation pages, or if your current one is acting up, water heater repair. Call (765) 664-4328 any time, day or night, or book online.