The Pros and Cons of Switching to a Tankless Water Heater

updated May 5, 2019
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If the idea of constantly heating your water in a big tank sitting in your basement sounds mighty inefficient and wasteful to you, then a tankless water heater may be the right option for you. I’ve researched some of the advantages of a tankless water heater system, alongside some of the compromises that come with the compact, more energy efficient option.

Tankless Water Heater Pros

There are many advantages to going with a tankless water heater. From increased energy efficiency and lowered operating costs to space savings and extended lifespan, find out more about what makes for good reasons to go tankless.

Energy Savings / Operating Costs
The first thought on tankless water heaters is generally: how much energy/money am I going to save? Well right off the bat, you’re going to be spending more money to get a tankless water heater and all its plumbing in place. While a tankless water heater costs more upfront, your operating costs down the line should start to make up for it. What you’re saving is in not having to spend money on standby heat, meaning you’re not wasting money heating water in a tank that’s just sitting idly waiting for someone to need hot water. Tankless systems provide that hot water on demand, when you need it, so you don’t have to waste energy heating unused water. You’re also not losing heat that’s idly sitting in a tank that, while insulated, is still going to lose heat and require constant reheating.

While a typical tank water heater is supposed to last 10 to 13 years, tankless water heaters are estimated to last up to 20 years. If you’re planning to stay in your home for a while, that’s a hefty replacement fee you’re saving. Even if you’re not going to stay in your home for that long, it’s nice to pay it forward towards the overall cost savings of home ownership.

Space Savings
Even if you weren’t concerned about saving money and energy, one of the big advantages of tankless water heaters is the potential space savings. Traditional water heaters with 40 to 60 gallon capacity are generally around 60″ tall and 24″ wide. That bulky metal tank can take up precious real estate in a home where space is at a premium. A tankless water heater, in comparison, might be the size of a large computer, perhaps 20″ wide by 28″ tall and just 10″ deep.

Tankless Water Heater Cons

While the case for tankless water heaters might sound like a no brainer, there are several reasons why going this route might not be for you.

Limited Output
A big tank water heater that stores 40 to 60 gallons of hot water at a time will keep your showers, laundry, and other hot water needs properly satisfied for quite some time. Modern tanks reheat additional supply quite quickly as well, so you’ll quite likely never run out of hot water when you need it. A tankless water heater has a throughout limit, able to supply a few gallons of hot water at all times but also at a time. So if you have a large family and everyone’s taking a shower, doing the laundry and dishes at the same time, a tankless water heater might not be up to the task or suitable for your family’s particular needs.

Additional Cost
While a typical tank water heater might be as cheap as $300-$400, they can price out up to $1,000 depending on options. But if you consider a tankless water heater probably costs $200-300 more (plus installation), you’ve got a pretty big difference in price tag. (Although in recent years, the prices have come down considerably.) Of course, the idea is to make up for that extra cost as you use less energy along the way, but still, having to put up that money up front isn’t always an option for everyone.

Instantaneous Energy Requirement
A traditional gas water heater might use 30,000 to 50,000 BTU of natural gas or propane while it’s heating up your water. A tankless water heater might require perhaps 150,000 to 200,000 BTU to do the same as it heats up your water on demand. Sometimes this high BTU requirement isn’t possible, as I found out myself during my own home renovation, where there’s a low pressure main, so we’re limited to a fairly low total BTU spread among all of our gas appliances. If you consider switching to electric instead of gas, you’ll need to be sure that your electrical system is up to the task. The price of electricity is usually higher than natural gas in many areas too, so you’ll need to consider the cost of energy as well.

Tankless Water Heater Installation

Consider hiring a licensed professional when swapping out your traditional hot water heater for a tankless model. In addition to removing the old unit, you’ll need to reconfigure the space to accommodate the new one. For electric systems, this requires knowing the voltage and amperage requirements of a tankless heater, and (as mentioned above), upgrading if necessary. For gas systems, you will likely need a new, larger gas line and proper ventilation.

Tankless Water Heater Reviews

Amazon’s choice is this EcoSmart electric tankless water heater, which gets a average four star rating for its price, reliability and company backing. It comes with a remote to control temperature, regardless of where you are in the home, and a lifetime warranty when professionally installed.

See more of their tankless water reviews here.

• Location is Important with a Tankless Water Heater
• Tankless Water Heaters: Worth the Extra Work?
• Why It’s Green: On-Demand Hot Water