Tankless vs. Tank Water Heater Replacement in Ann Arbor, MI: An Honest Guide

One of the most common questions we get at Wright Mechanical from customers in Ann Arbor, Ypsilanti, and across Washtenaw County who need to replace their water heater is: "Does it make sense to install a tankless water heater in my home?" The answer is always, "It depends." To give you the right answer, we need to know about your hot water usage, where your current water heater is installed, and why you're interested in going tankless. There are many factors that play into whether tankless is the right fit for your home.

It's All About Flow

With a tank water heater, you have forty, fifty, or even seventy-five gallons of hot water ready to go whenever you need it. Once that stored hot water is used up, you're waiting for the tank to reheat, and the temperature at your faucet or shower will slowly start to drop. If you've ever had to turn up the hot water mid-shower just to keep the temperature steady, you've experienced a tank running low.

Tankless water heaters work differently: they heat water instantly as it passes through the heat exchanger. That means there's a limit on how much water can flow through at once and still reach your desired temperature. If your home demands more flow than the unit can handle (think showers with multiple sprayers or two bathrooms running at the same time), one tankless unit may not be enough. With a tank, you're managing stored capacity. With tankless, you're managing flow rate.

Tankless Installation: What Changes in Your Home

Standard tank water heaters use around 40,000 BTUs to gradually heat water stored in the tank. A BTU is a unit of energy, specifically the amount of energy needed to raise one pound of water by one degree Fahrenheit. Tankless water heaters use between 180,000 and 199,000 BTUs because they have to heat water instantly instead of gradually. That jump in energy demand has real implications for Ann Arbor and Ypsilanti homeowners considering the switch.

Gas line sizing. Your existing gas line may need to be upsized to supply the higher BTU demand. In finished basements where the gas line isn't easily accessible, this can add significant cost. In some cases, the gas meter itself needs to be upgraded. It doesn't happen on every job, but we do run into it. This is one of the main reasons we need to do a thorough in-home assessment before giving you an accurate quote.

Venting. Tankless units vent with PVC because they're so efficient that their exhaust gases are cool enough not to melt plastic pipe. If you're replacing a standard atmospheric-vent tank that currently vents through a chimney or metal vent pipe, we'll need to install two new PVC pipes going outside: one for incoming air and one for exhaust. That's two new wall or roof penetrations that don't exist today. If you already have a power-vent tank, you'll only need one additional PVC pipe.

Condensate removal. Because of their high efficiency, tankless water heaters produce condensate as a byproduct of combustion, something most traditional tanks don't produce at all. That condensate is acidic and must be neutralized before it enters a drain. If there's no floor drain nearby, a pump will be needed to move the neutralized condensate to a floor drain, laundry tub, or sump pit.

All of these factors (gas line, venting, and condensate) need to be weighed when deciding if tankless is right for your home. At Wright Mechanical we can overcome all of these obsticles, but the cost of overcoming them is part of the equation of the total installation cost.

What Does Water Heater Replacement Actually Cost in Ann Arbor?

A tank water heater replacement from Wright Mechanical in Ann Arbor typically runs $1,500 to $3,000 installed, depending on the type of unit and the complexity of the job. Tankless water heater installation is more involved and generally falls between $3,000 and $6,000 installed. That gap reflects both the higher equipment cost and the added installation complexity described above.

When switching from a tank to tankless, the location of the water heater often changes: sometimes by a few feet, sometimes by ten to twenty feet. That shift means water lines, gas lines, and venting all need to be relocated, which adds to the total cost.

It's also worth factoring in lifespan. A tank water heater typically lasts 8 to 12 years. A tankless unit that's properly maintained can last 15 to 20 years, nearly twice as long. Over time, that extended lifespan helps offset the higher upfront investment.

The Real Energy Savings: What the Numbers Actually Show

Efficiency is one of the top reasons homeowners in Washtenaw County ask about tankless, and it's true: tankless units are more efficient. But let's look at what that actually means on your energy bill.

Every water heater comes with a yellow Energy Guide label from the U.S. government showing the estimated yearly energy cost. Here's how three common natural gas models we install compare:

Water Heater	Type	Est. Annual Energy Cost
Bradford White RG250T*N	Atmospheric vent, 48 gal	$325/year
Bradford White RG2PV50S*N19	Power vent, 48 gal	$292/year
Navien NPE-240A2	Tankless	$219/year

Switching from an atmospheric-vent tank to a Navien tankless saves an estimated $106 per year on your gas bill. If you already have a power-vent tank, the savings shrink to about $73 per year. Over the 15-to-20-year life of a tankless unit, that does add up, but it probably doesn't erase the higher upfront cost on its own.

And there's another variable: we've seen plenty of cases where the gas bill doesn't go down at all after switching to tankless. The reason is usually a change in behavior. When you suddenly have endless hot water and no fear of running out, it's natural to take longer showers. If everyone in the household does that, the efficiency savings can disappear quickly. The technology is more efficient, but how you use it matters just as much as what you install.

One important note: these figures are for natural gas, which is what most homes in Ann Arbor and Washtenaw County run on. Propane costs significantly more to operate across all three types, so if you're on propane (as some homeowners in the more rural parts of Washtenaw County are), factor that into your comparison.

Ann Arbor's Hard Water and Tankless Maintenance

Tankless water heaters are more susceptible to hard water than tank units. Ann Arbor's water supply runs hard, which makes this more relevant here than in many other parts of Michigan.

Here's why it matters: as water flows through the heat exchanger and gets rapidly heated, minerals come out of solution and stick to the heat exchanger, similar to the white buildup you see inside a pot after boiling water. That mineral scale reduces efficiency and heat transfer over time, and if left unchecked, it can shorten the life of the unit.

We recommend an annual descaling visit for tankless units: a cleaning solution is run through the heat exchanger to flush out the buildup. Depending on your specific water quality, you may be able to stretch that to every two years, but it's maintenance you need to plan and budget for. A standard tank water heater, by contrast, requires very little ongoing attention.

The Real Advantage: Endless Hot Water

Here's where tankless water heaters genuinely shine. As long as the flow rate stays within what the unit can handle, you get endless hot water. Theoretically, you could run a shower indefinitely and never run cold. With a tank, that's simply not possible. Eventually the stored hot water runs out.

If you grew up in a house with siblings and a tank water heater, you know what it meant to be last in line for the shower. Tankless eliminates that entirely.

Tankless also gives you precise digital temperature control. The water comes out at exactly the temperature you set and stays there. With a tank, you end up adjusting the shower as the hot water depletes and the temperature drifts. No more chasing the temperature.

Space is another benefit, especially if your current tank is in a main-floor closet. A tankless unit mounts to the wall, freeing up meaningful storage space in your home.

When Tankless Makes the Most Sense

Tankless is a genuinely great fit for homeowners who want endless hot water and precise temperature control. People who've lived with a tankless unit tend to love it. It's one of those things that's hard to fully appreciate until you've experienced it firsthand.

It also makes a lot of sense for vacation homes, lake houses, or seasonal properties in the Washtenaw County area where hot water use is sporadic. There's no good reason to keep fifty gallons heated around the clock when a property sits empty for weeks at a time. Tankless only heats water when you need it, which makes it naturally more efficient in those situations.

The Bottom Line

For most Ann Arbor and Ypsilanti homes, a tank water heater is still the right call. It's less expensive to install, simpler to maintain, and works reliably for everyday use. For homeowners who want endless hot water, precise temperature control, better long-term efficiency, or who own a property that sits empty for stretches of time, tankless is worth the investment.

Either way, the decision should be based on your actual situation, not a sales pitch.

If you're not sure which option is right for your home in Ann Arbor, Ypsilanti, or anywhere in Washtenaw County, give us a call at 734-684-0030 or visit wrightmech.com. We'll come out, take a look, and give you the honest answer, no pressure, no upsell.

Frequently Asked Questions: Tankless vs. Tank Water Heaters

I heard tankless means instant hot water. Is that true?

This is probably the most common misconception we hear at Wright Mechanical. Tankless does not mean instant hot water. In fact, most of the time it's the opposite. With a tank water heater, hot water is already sitting in the tank and migrating out into your pipes, so when you turn on the faucet, it's already partway there. With a tankless unit, there's no stored hot water. Before any hot water can reach your fixture, the unit has to detect flow, start the motor to vent the flue gases, verify the motor is working, fire the burners, and ignite the gas. All of that takes time. Unless you have a recirculation line installed, you'll typically wait longer for hot water from a tankless unit than from a tank.

What changes are needed to switch to tankless in an Ann Arbor home?

It depends on your home, but there are a few things we check on every tankless installation. First is your gas line. In many cases it will need to be upsized, which can add cost, especially in finished basements where access is limited. In some cases the gas meter itself needs to be upgraded. Next is venting: tankless units require two PVC pipes going outside, one for incoming air and one for exhaust. If you currently have a standard atmospheric-vent tank, that's two new penetrations through your wall or roof. And because Ann Arbor homes vary a lot in age and layout, the best thing we can do is come to your home and do a full assessment before you commit to anything.

How long do tankless water heaters last compared to tank units?

This is one area where tankless has a clear advantage. A tank water heater typically lasts 8 to 12 years. A tankless unit, when properly maintained, can last 15 to 20 years. That longer lifespan is a real part of the ROI calculation when weighing the higher upfront cost of going tankless, especially for Ann Arbor and Ypsilanti homes getting regular year-round use.

What maintenance does a tankless water heater need?

The main service item is descaling the heat exchanger. As water flows through the unit and gets rapidly heated, minerals (especially relevant given Ann Arbor's hard water) build up on the heat exchanger over time. That buildup reduces efficiency and can shorten the unit's life if left unchecked. We recommend annual descaling under typical water conditions. If your water quality is better than average, you may be able to stretch to every two years. It's a straightforward service visit, but it's something to plan and budget for that you wouldn't have with a tank.

How do I know if my gas line or meter needs to be upgraded for tankless?

You won't know for sure until someone looks at your home. That's not a dodge; it's genuinely home-specific. The size of your existing gas line, the distance to the meter, what else is on the line, and the location of the water heater all factor in. At Wright Mechanical, we do a full assessment before quoting any tankless installation in Ann Arbor or Washtenaw County. Visit our contact page to schedule a visit  and we'll set up a time to come take a look.

Wright Mechanical is a locally owned HVAC and plumbing contractor serving Ann Arbor, Ypsilanti, and Washtenaw County. Licensed, honest, and not private equity-backed. wrightmech.com | 734-684-0030

About the Author

Terry Marts is a licensed mechanical contractor and the General Manager of Wright Mechanical, a locally owned heating, cooling, and plumbing company serving Ann Arbor, Ypsilanti, and the surrounding southeast Michigan communities. Terry holds an Associate's degree in HVAC from Washtenaw Community College, a Bachelor's degree in Technology Management from Eastern Michigan University, and a Master of Business Administration from the University of Iowa. With hands-on experience installing and servicing both tank and tankless water heaters across Washtenaw County, Terry has helped Ann Arbor and Ypsilanti homeowners navigate the real costs, installation requirements, and long-term trade-offs of switching to tankless. Wright Mechanical is independently owned, not private equity backed, and committed to honest, straightforward service for every customer.