How to choose the right water heater for a North Shore home
A tank water heater costs less to install and is the safer choice if you need hot water back today. A tankless water heater costs two to three times more up front, lasts about twice as long, uses less energy, and never runs out of hot water. Which one is right depends on how much hot water your house uses, what your gas line and venting can support, and how long you plan to stay.
Most calls we get about water heaters start the same way: the old one is leaking or the shower went cold, and the homeowner wants to know if this is the time to go tankless. Here’s what we tell them.
What is the difference between a tank and a tankless water heater?
A tank water heater is a steel cylinder holding 40 to 80 gallons of water that it keeps hot around the clock. When you open a hot tap, hot water leaves the top of the tank and cold water refills the bottom. Use it all and you wait for the tank to recover.
A tankless water heater has no storage. When a hot tap opens, water runs through a heat exchanger and a gas burner (or electric elements) heats it on the way through. Close the tap and it shuts off. You get hot water for as long as the tap is open, but only as much per minute as the unit is rated to deliver.
How long do tankless and tank water heaters last?
A tank lasts 10 to 15 years. The tank itself is the weak point: sediment settles in the bottom, the steel eventually rusts through, and once it leaks the whole unit gets replaced. Water on the North Shore comes from Lake Michigan and is moderately hard, so sediment builds up faster than in soft-water areas and tanks here tend to die on the early side of that range unless they’re flushed.
A tankless unit lasts 20 years or more. The parts that wear, like the heat exchanger, igniter, and flow sensor, can be replaced individually, so the unit doesn’t get scrapped when one thing fails. The catch is maintenance. Hard water leaves scale inside the heat exchanger, and a tankless unit that never gets flushed loses efficiency and can fail early.
What does each one cost to install?
National cost guides put a replacement tank at roughly $1,500 to $3,200 installed and a tankless unit at $3,500 to $7,000 installed. Your number depends on the house.
Swapping a tank for a new tank is a straightforward job, usually done in a few hours with the existing gas line, water lines, and vent. Converting from a tank to tankless can involve more, and this is where surprise costs come from:
- A larger gas line. A gas tankless burner is much bigger than a tank burner, and many older homes have a gas line too small to feed it.
- New venting. Condensing tankless units vent through PVC out a side wall rather than up the old chimney flue.
- A condensate drain, since condensing units produce water as they run.
- Water treatment. With our water hardness, some homeowners add a scale filter or softener to protect the heat exchanger.
- For electric tankless, a panel upgrade. Whole-house electric tankless units draw more power than most Illinois homes’ panels can spare, which is why nearly every whole-house tankless installation here is gas.
We look at all of this before we quote, so the price you get is the price you pay.
How much energy does a tankless water heater actually save?
Less than the ads suggest, but real. The Department of Energy puts the savings at 24 to 34 percent for a household that uses relatively little hot water (about 40 gallons a day), and 8 to 14 percent for a household that uses a lot (around 86 gallons a day). The reason is that a tank wastes energy keeping water hot when nobody’s using it, so the less hot water you use, the bigger share of your bill that waste is. For a typical gas household that works out to somewhere around $100 a year.
On savings alone, a tankless unit takes a long time to pay back its extra cost. Most people who go tankless do it for the endless hot water and the longer life, with the energy savings as a bonus.
Gas, electric, or heat pump?
Gas tank and gas tankless are the two common choices here, and everything above applies to both. Two others come up:
Electric tank water heaters are inexpensive and simple but cost more to run than gas in our area. They make sense where there’s no gas service.
Heat pump (hybrid) water heaters are electric tanks that pull heat from the surrounding air instead of making it with an element. They use roughly a third of the electricity of a standard electric tank and are the most efficient option available. They need a fair amount of space around them, a basement or utility room that stays above 40 degrees, and a condensate drain, and they cool the room they sit in. They also qualify for utility rebates and tax credits more often than any other type, which can close most of the price gap. Worth asking about if you’re replacing an electric tank.
How big a water heater do I need?
For a tank, size by household. For tankless, size by how many hot fixtures you’d run at the same time, measured in gallons per minute. A shower is about 2 gallons per minute, a washing machine about 2, a dishwasher about 1.5, a bathroom faucet about 1.
One thing the box won’t tell you: tankless ratings assume the incoming water is fairly warm. In a Chicago-area winter, water comes into the house at 40 to 50 degrees and has to be raised 70 degrees or more, so a unit rated at 9 or 10 gallons per minute may deliver closer to 5 or 6 in January. We size for winter, not for the label.
Who is a tankless water heater NOT right for?
A few situations where we’d steer you toward a tank:
- You need hot water today and the budget is tight. A tank goes in the same day for a fraction of the cost.
- You’re planning to sell within a few years. You won’t recoup the difference in energy savings, though it’s a nice selling feature.
- Your household uses very little hot water. The savings are highest in that case, but the dollar amount is small.
- Big house, several bathrooms, and everybody showers at 7 a.m. One tankless unit can hit its flow limit and the water gets lukewarm. The fix is two units or a large tank, and the large tank is cheaper.
- The gas line, venting, or electrical panel would need major work to support it.
Signs your water heater is about to fail
- It’s more than 10 years old. Check the manufacture date on the label.
- Rusty or discolored hot water.
- Rumbling or popping noises when it heats. That’s sediment on the bottom of the tank.
- Water around the base. Once a tank leaks, replacement is the only fix.
- Hot water runs out faster than it used to.
If you’re seeing two or more of these, replace it on your schedule rather than waiting for it to let go on a holiday weekend.
Maintenance that actually matters
For a tank: flush it once a year to clear sediment, and have the anode rod checked every few years. The anode rod is a sacrificial metal rod inside the tank that corrodes so the tank doesn’t. Replacing it for a modest cost can add years to a tank’s life.
For tankless: flush it with a descaling solution once a year. With our water, every 12 months, not every 18. Skipping this is the most common reason we see tankless units fail before their time.
Frequently asked questions
Is a tankless water heater worth the extra cost?
For a family that uses a lot of hot water and plans to stay in the house 7 years or more, usually yes. You get endless hot water, a unit that lasts twice as long, and lower bills. For a small household or someone moving in a few years, a good tank is the better value.
Can a tankless water heater freeze in an Illinois winter?
Indoor units installed in a basement or utility room with built-in freeze protection are fine. We don’t recommend outdoor tankless units in this climate.
How often does a tankless water heater need maintenance?
A descaling flush once a year. Homes with a water softener can sometimes stretch that, but annual is the safe schedule with Lake Michigan water.
Will a tankless water heater increase my home’s value?
It’s a selling point, especially for a finished basement where the floor space matters, but the main return is the energy savings and long life while you’re living there. Don’t buy one for resale alone.
Do I need a water softener with a tankless water heater?
Not required, but with moderately hard water a scale filter or softener protects the heat exchanger and keeps the warranty in good standing with some manufacturers. We’ll tell you whether your water calls for it.
Can I switch from a gas tank to a gas tankless in an older North Shore home?
Almost always, but the gas line size and vent path decide how much work it is. That’s the first thing we check on a site visit.
Water heater installation on the North Shore
Biagi Plumbing has been installing and servicing water heaters on the North Shore since 1989. We install tank, tankless, and heat pump water heaters in Evanston, Wilmette, Winnetka, Glencoe, Highland Park, Lake Forest, Lake Bluff, Deerfield, Northbrook, Glenview, Libertyville, Buffalo Grove, and the surrounding communities.
Whether your tank just started leaking or you’re weighing a switch to tankless, call Biagi Plumbing at (847) 512-8921. We offer same-day service, so if you’re out of hot water we can usually have a new tank in today. And if you’re considering tankless, we’ll look at your gas line, venting, water, and how your household uses hot water, and give you a written price on the option that makes sense for your house, not a sales pitch for the most expensive one.