Looking to replace your hot water heater? Tankless water heaters are an increasingly popular choice among homeowners.
Tankless Water Heater Guide
Learn more about how tankless water heaters work and their potential advantages over storage tank water heaters.
What is a tankless water heater?
Instead of heating water and storing it in a tank, a tankless water heater provides hot water on-demand. That is, when you turn on your hot water, cold water flows into the heating unit, where it is heated by gas or electricity.
Tankless water heaters are sometimes referred to as instantaneous, flash, on-demand or instant-on water heaters.
What are the advantages of having a tankless water heater?
Tankless water heaters require less space and are typically more energy-efficient than storage tank water heaters; they also allow you to set the thermostat to your desired temperature. Moreover, because the tankless only heats when the water is passing through it, no pressure builds in system, which limits possibility of catastrophic leaks such as a ruptured tank.
Factors to consider when selecting a tankless water heater
- Size; units are rated by maximum temperature rise possible at a given flow rate (gallons per minute)
- Fuel type availability (natural gas)
Also, a tankless water heater typically requires properly sized gas lines to operate correctly, upgrades are common when retrofitting a standard tank style heater to a natural or liquified petroleum (LP) gas tankless water heater.
How big of a tankless hot water heater do I need?
The size you need is dependent on three factors. The first is groundwater temperature—the temperature of the water when it enters the unit. In Middle Tennessee groundwater temperature is circa 57 degrees, so if you want a 105-degree shower you need a 48-degree temperature rise, which is the second part of the equation.
Finally, you need to consider the hot water flow rate and whether it is adequate for the shower head(s) and faucet(s) in question. An experienced plumber can help you determine the size you need to meet the expectations of your household.
How much hot water does a tankless water heater provide?
According to energy.gov, tankless water heaters provide hot water at a rate of two to five gallons per minute, with gas-powered heaters typically producing higher flow rates than electric units.
Are tankless hot water heaters more energy efficient?
Yes. According to energy.gov’s tankless water heaters page, “for homes that use 41 gallons or less of hot water daily, demand water heaters can be 24%-34% more energy efficient than conventional storage tank water heaters.
[And] they can be 8%-14% more energy efficient for homes that use a lot of hot water … with ENERGY STAR® estimating that the typical family can save $100 or more per year with an ENERGY STAR®-qualified tankless water heater.”
Proper installation and maintenance can help optimize a tankless water heater’s energy efficiency.
Is a tankless water heater worth the money?
Tankless water heaters are more expensive than storage tank heaters, but Consumer Reports reminds us that “the cost of heating water consumes almost 20 percent of your household budget, second only to what you spend on heating and cooling your home.”
So you may recover the additional upfront cost via lower utility bills. A reputable plumber can help you calculate the length of the “payback time,” and whether a tankless water heater will likely deliver financial savings as compared to a storage tank unit.
Are tankless water heaters “better”?
In many cases, a tankless water heater is the best way to go, but an experienced plumber can help you analyze all the factors worth considering—including your needs, preferences and budget—to determine the best options for your home and household.
Should I consider a tankless water heater?
If your current water heater has failed or is nearing the end of its useful life, you have better choices than ever before, “thanks to recent federal regulations that require new water heaters to be more energy-efficient,” notes Consumer Reports magazine. “New storage tank water heaters are required to operate more efficiently, and tankless water heaters are even more efficient than that [emphasis added].”
One big factor, though, is whether your current hot water heater runs on natural gas or electricity. If you need to retrofit your plumbing or enhance your electrical system—or switch from electricity to gas—it might make a tankless system prohibitively inconvenient or expensive.
On the other hand, “if you’re building a new home of adding to an existing one, installing a tankless water heater might make economic sense,” notes the magazine.
What is the life expectancy of a tankless water heater?
On average, a tankless water heater lasts 15-20 years, or 5-10 years longer than a conventional hot water heater. They also have readily replaceable parts that help extend their lifespan and typically come with a longer warranty (12 years) than a storage tank heater.
Are there any drawbacks to a tankless water heater?
The primary drawback is that a tankless unit can cost up to three times as much as a conventional tank water heater, though “capacity expansion, mergers and acquisitions of prominent tankless water heater manufacturers … is helping to lower the overall cost of tankless water heaters.”
At the same time, tankless water heaters may require more maintenance (depending on the hardness of the water in your area) and may not be able to supply multiple appliances simultaneously. This explains why some homeowners dedicate a tankless unit for each individual appliance or install two or more tankless units, which can be connected in parallel to address high demand.
Also, a tankless unit typically requires a high-pressure gas line; if you want to install an electric tankless hot water heater, upgrades to your electrical system may be required.
Most common problems experienced with tankless water heaters
- Mineral buildup inside the unit
- Venting or air supply issues
- Ignition failure
- Flame failure
Most problems with tankless water heaters involve lack of proper maintenance, an ounce of prevention is worth a pound of cure! Maintain it now or pay for it later.
Indications that your tankless water heater needs repair or replacement
If there’s no hot water or the water isn’t hot enough, that could indicate a problem with your natural or liquified petroleum gas and a repair is needed. If there’s a leak, water may puddle at the base of the unit—or you might notice a drop in water pressure. and a repair is needed. If there’s a leak, water may puddle at the base of the unit—or you might notice a drop in water pressure.
Finally, strange noises—including a gurgling, bubbling or hissing sound—is a warning sign that should be investigated by an experienced plumber as soon as possible.
Call Jewell Mechanical for tankless water heater installation or service
Our plumbing technicians offer a variety of plumbing services and have many years of experience and we offer 24-hour emergency service for emergency situations. In most cases, we can provide same-day replacement for water heaters, whether you’re in Davidson County or elsewhere in Middle Tennessee. Check out our promotions for tankless water heaters. Contact us online or call us at (615) 469-5965.