Learn the top pros and cons of a traditional water heater and a tankless water heater

When it comes to your water heater, you probably only have one concern: that it works. But if you need to invest in a new system soon, you should understand the differences between traditional and tankless units to ensure you pick the best option. The expert plumbers at Seider Heating, Plumbing & Electrical share the main pros and cons of each and explain why you should weigh your options carefully before taking the plunge.

What is a traditional water heater?

Traditional water heaters—also known as storage tank water heaters—are the most common unit type. They are insulated water tanks which continuously heat and store between 30 and 50 gallons of water. When you need hot water, a pipe connected to the top of the unit immediately draws the water out of the tank and sends it to fixtures, like your washing machine, kitchen sink, or shower. The two main energy sources are natural gas or electricity, with natural gas tanks using up to 50 percent less energy than their electrical counterparts. Below are the top pros and cons of these common systems:

  • More affordable to buy and install than a tankless water heater (can save you thousands)
  • Simpler systems than tankless units, so maintenance, repair, and installation cost less
  • Readily available and easily replaced when the time comes


  • Higher utility bills (compared to tankless) because the water must constantly be heated
  • Bigger in size—they take up more space (usually in your basement or a utility room)
  • Shorter lifespan—can last anywhere between 10 to 15 years, which is roughly half the lifespan of a tankless option

What is a tankless water heater?

Rather than storing hot water, tankless water heaters—also known as on-demand water heaters—only heat water when you need it. Cool water enters the tankless unit and leaves a split-second later once it reaches the desired temperature. These units are smaller in size and are mounted on the wall, taking up far less space than traditional units. Tankless systems run on either a gas burner or electric heating coil and are up to 30 percent more efficient compared to traditional units. But to reap the money savings, you’ll have to pay a higher initial price tag. Here are the top pros and cons of tankless units:

  • Longer lifespan compared to traditional storage water heaters (up to 30 years)
  • Takes up far less space than a storage tank does and is simply mounted on the wall
  • No delay waiting for hot water to come out of the faucet—it’s ready when you are


  • Higher average purchase cost upfront (roughly four to six times more expensive)
  • Retrofitting a traditional heater to a tankless is complicated and costly
  • Because capacity is smaller (two to three gallons per minute), you may run out of hot water if multiple fixtures or appliances run at one time

Need Help Picking a Water Heater? Just Ask

Our professional plumbers have decades of experience recommending and installing water heaters and would be happy to help you pick one. You already trust us with your Carrier® heating and cooling systems—it makes sense to trust us for plumbing, too. Give us a call or schedule an appointment today.