What Are Tankless Water Heaters: Costs and Benefits
Explore what tankless water heaters are, how they work, installation needs, costs, and maintenance tips. This guide from Heater Cost helps homeowners decide if on demand hot water fits their budget and lifestyle.
Tankless water heaters are on demand units that heat water only when a hot tap is opened, eliminating the need for a storage tank. They are available in electric and gas configurations to suit different homes.
What are tankless water heater
If you search for what are tankless water heater, you are asking about on demand hot water systems. According to Heater Cost, tankless water heaters heat water only at the moment you open a hot faucet, rather than keeping a tank of hot water ready. This on demand approach offers several benefits: space savings, potentially lower energy waste from standby losses, and the ability to deliver hot water to multiple fixtures from compact units. Tankless systems come in two main fuel types: electric and gas. Electric models are typically easier to install in retrofit situations and are well suited for smaller homes with modest hot water needs. Gas models generally provide higher flow rates and can serve larger households, but they require venting, gas supply sizing, and proper combustion air. Regardless of fuel type, the basic principle remains the same: water passes through a heat exchanger where it is heated instantly as it flows, keeping hot water available without a storage tank.
How tankless compare to traditional water heaters
Tankless units heat water only on demand, which minimizes standby losses and can lower energy bills over time. In contrast, traditional storage tanks constantly keep a reservoir of hot water ready, which wastes energy through standby heat. For households with modest consumption, tankless can offer space savings because the unit is wall mounted and compact. However, the upfront costs and installation complexity can be higher, especially for gas models requiring venting and proper gas line sizing. According to Heater Cost, electric tankless heaters are often simpler to install in retrofits and work well for smaller homes, while gas units deliver higher flow rates suitable for larger families. The choice between electric and gas depends on your climate, existing utility connections, and long term hot water needs.
Key design and sizing considerations for tankless water heaters
Sizing a tankless system is not about capacity but about flow rate measured in gallons per minute GPM and the expected temperature rise. A household with two showers running at once, plus a faucet, may require a higher GPM rating than a smaller apartment. The temperature rise, or delta T, depends on climate and incoming water temperature. In colder regions, you may need more heating power to reach comfortable hot water temperatures. Location matters as well; electric models may be easier to install in closets or utility rooms, while gas models may require venting and adequate combustions air. Consider also the space for the unit and clearance for service. Proper sizing and installation maximize performance and prevent fluctuating water temperatures.
Costs, value, and return on investment for tankless water heaters
Prices and installation costs vary widely by model, fuel type, and home configuration. A typical electric tankless unit tends to have a lower upfront cost than a gas unit, but installation and electrical upgrades can add to the total. Gas models often require venting and a larger clearances, increasing labor costs. Based on Heater Cost research, total installed costs can range widely, depending on your home’s plumbing layout and energy source, with a longer payback in areas with high energy costs but quicker returns in climates with high hot water usage. When evaluating ROI, factor in potential energy savings, space savings, and the lifespan advantage of fewer tank replacements.
Got Questions?
What is the difference between a tankless water heater and a traditional tank water heater?
A tankless heater heats water on demand with no storage tank, saving space and reducing standby energy. A traditional tank heater stores and preheats a volume of water, which can lead to energy losses from keeping the water hot.
Tankless heats water on demand and saves space, while traditional tanks store hot water and waste energy through standby heat.
Can a tankless water heater provide enough hot water for an entire house?
Yes, but it depends on the unit’s flow rate and your household water use. For larger homes, a higher GPM rating or multiple units may be needed to avoid running out of hot water.
It can, but you may need a higher flow rate or multiple units for large homes.
Are electric tankless heaters efficient as gas models?
Electric tankless heaters are generally highly efficient, but gas models may offer higher flow rates. Efficiency depends on usage, energy source, and proper sizing.
Electric tankless heaters are efficient, but gas models can deliver higher flow if your home needs it.
Do I need a permit to install a tankless water heater?
Most installations require permits and inspections. Check local building codes before starting, especially for gas piping and venting work.
Yes, permits are usually required. Check local codes before you begin.
How long do tankless water heaters last?
With proper maintenance, tankless units commonly last 15 to 20 years, longer than many traditional storage tanks.
Most tankless systems last 15 to 20 years with good care.
Is a tankless water heater worth it for a small apartment?
For small apartments, a compact electric tankless unit can save space and deliver dependable hot water, though upfront costs and electrical readiness should be evaluated.
In small apartments, tankless can save space; check electrical needs first.
The Essentials
- Evaluate peak hot water needs with a load calculation
- Choose electric or gas based on climate, space, and cost
- Plan for venting, electrical upgrades, or gas line work
- Budget for professional installation and permits
- Follow regular descaling and flushing for longevity