Gas or Electric Tankless Water Heater: Which Should You Choose?
I’ve been in enough crawl spaces and basements to know that choosing between gas or electric for your tankless water heater isn’t as straightforward as most people think. Just last week, a homeowner told me, “I don’t care if it’s gas or electric—I just want hot water that doesn’t run out during my shower.” Fair enough, but the choice between gas or electric makes a bigger difference than you might realize.
Here’s the thing: I’ve installed both types in hundreds of homes and seen how the decision can make or break your satisfaction with a tankless system. Some folks are thrilled with their choice, while others wish they’d gone the other route. Let me walk you through what I’ve learned so you can make the right call for your situation.
The Real Performance Difference: Gas or Electric Power
When it comes to raw heating power, gas or electric isn’t a fair fight—gas wins hands down. A gas tankless unit can heat water significantly faster than an electric one, meaning better flow rates and the ability to supply multiple outlets simultaneously.
I remember working on a house with four teenagers. The parents were debating gas or electric, and I told them straight up: “With your family’s shower schedule, you need gas.” Electric units work great for smaller households or single-bathroom situations, but when multiple people are trying to shower, run the dishwasher, and do laundry all at the same time, gas gives you the power you need.
That said, electric units aren’t slouches. They’re perfect for point-of-use applications or homes where hot water demand is more predictable. The key is matching the gas or electric choice to your actual usage patterns, not just going with what sounds better on paper.
Installation Reality Check: Gas or Electric Complexity
This is where things get interesting. When people ask me about installation costs, I always start with what their home already has. If you’ve got a gas line running to your current water heater location, gas becomes much more attractive. But if you’re starting from scratch, the gas or electric equation changes dramatically.
Electric tankless units are generally easier to install, especially in homes without existing gas infrastructure. You don’t need venting, which saves on materials and labor. However—and this is a big however—electric units often require significant electrical upgrades. I’ve seen plenty of homeowners get sticker shock when they realize their electrical panel needs an upgrade to handle the amperage demands of an electric tankless system.
Gas installations require proper venting, and sometimes, new gas lines are run. However, if the infrastructure is already there, the choice of gas or electric often favors gas. It really depends on your specific situation.
The Money Talk: Gas or Electric Operating Costs
Let’s be honest about the financial side of the decision. In most areas, natural gas is cheaper per BTU than electricity, which means lower monthly operating costs for gas units. I’ve had customers save $30-50 per month switching from electric to gas tankless systems.
But here’s what complicates the gas or electric cost comparison, electric units are more efficient at converting energy to heat. They don’t lose energy through venting like gas units do. So while gas might be cheaper per unit of energy, electric units waste less of that energy.
The honest answer depends on your local utility rates. I recommend getting recent gas and electric bills to do the math. Sometimes the choice that seems obvious based on general advice doesn’t make sense for your specific location and usage patterns.
Maintenance and Longevity: Gas or Electric Reliability
This is where my experience really shows the difference between gas or electric systems. Gas units have more components that can fail—igniters, burners, venting systems, and gas valves. They need more regular maintenance, especially in areas with hard water where mineral buildup can affect the heat exchanger.
Electric tankless units are simpler machines. Fewer moving parts means fewer things that can break. When I’m doing maintenance calls, electric units typically need less frequent service. The gas or electric reliability question often comes down to how much hands-on maintenance you’re willing to deal with.
Both types can last 15-20 years with proper care. Longevity concerns shouldn’t drive the choice—both are solid investments when installed and maintained correctly.
When Your Home Dictates the Decision
Sometimes the choice is made for you by your home’s existing infrastructure. If you’re in a rural area without natural gas service, electric is your only option. If you’re in an older home with limited electrical capacity, gas might be the only practical choice.
I’ve worked in homes where the gas or electric decision was essentially predetermined by the electrical panel’s capacity or the availability of gas lines. Don’t feel bad if your choice is limited—both options can work well when properly sized and installed.
Getting the Installation Right
Here’s what I’ve learned after years of tankless installations, the quality of the installation matters more than the choice itself. I’ve seen poorly installed gas units that never worked properly, and I’ve seen electric units that exceeded expectations because they were sized and installed correctly.
Whether you choose gas or electric, make sure your installer evaluates your actual hot water usage, sizes the unit properly, and handles all the electrical or gas work to code. A gas or electric system is only as good as its installation.
Special Considerations for Your Decision
The choice can also be influenced by factors you might not consider initially. If you’re concerned about power outages, gas units with pilot lights can sometimes continue working when the electricity is out. If you’re environmentally conscious, the choice might depend on your local power grid’s energy sources.
Some homeowners choose gas or electric based on their comfort level with the technology. If you’re nervous about gas appliances, electric might give you more peace of mind. If you’re used to gas appliances and trust the technology, gas might feel more natural.
Making Your Final Decision
So, what’s it going to be? After installing both types in every conceivable situation, I can tell you that both can be excellent choices. Gas units offer superior performance for high-demand situations, while electric units provide simplicity and can be perfect for the right application.
The decision should be based on your specific needs, existing infrastructure, local utility costs, and comfort level with the technology. Don’t let anyone tell you that gas or electric is universally better—the best choice is the one that fits your situation.
Take the time to evaluate your hot water usage patterns, get real cost estimates for both options, and consider the long-term implications of your gas or electric choice. With the right decision and proper installation, either option will give you years of reliable hot water.
