When your water heater starts making knocking noises or stops providing adequate hot water for your home—or, worse, it bursts—it’s time to decide on a replacement model that will best fit your needs. When you start looking into the options, however, you might feel overwhelmed by all the choices that are available. Which are better—tankless water heaters or tank water heaters? What are the advantages and disadvantages of each type, and which kind is right for your particular home?
If you’re considering making the switch from a traditional tank model to a tankless water heater, it could seem especially daunting to decide whether this is the right move. Tankless heaters typically have higher price tags than tank heaters, though their operating costs over time are lower. Even knowing they’ll likely save money over time, many people balk at the prospect of spending so much money up front.
Of course, there are other factors to consider besides cost. Both tank and tankless water heaters require basic maintenance in the form of annual flushing. Tankless water heaters eventually shut themselves off if they aren’t flushed on an annual basis. On the other hand, if tank heaters aren’t flushed annually (or more often if you have very hard water), these heaters can build up enough sediment in just five years that flushing at that point would become very difficult, if not impossible. There is also the average lifespan of the water heater to consider. These factors are just a few reasons why it’s important to weigh the pros and cons of both tank and tankless water heaters, so you can make an informed decision about which type is right for your home.
Tank Water Heater Pros and Cons
As you can see in the image above, tank water heaters are tall metal cylinders connected to pipes and hoses, and they are typically installed in the attic, basement or utility room. These water heaters may be gas or electric, but either way, they work by continuously keeping a large volume of water—usually between 40 and 75 gallons, depending on the size of the home—hot. Cold water from the home’s water pipes is fed into the water heater, where a heating element heats it up; the hot water inside the tank then rises to the top, where it is ready to be distributed throughout the home as needed through the heat-out pipe.
The main advantage that tank water heaters have over their tankless counterparts is the fact that they are less expensive to purchase and install. Aside from a lower up-front cost, however, tank water heaters have several cons to consider if you are thinking of having one installed in your home.
First of all, the lifespan of a tank water heater is shorter than that of a tankless water heater—typically only eight to ten years. Tank water heaters are also less efficient than tankless water heaters and therefore more costly to run, since they operate by keeping water hot continuously rather than heating it on demand. The average home equipped with a tank water heater will have a model with a hot water capacity of 40 to 50 gallons. This amount of water can be used up quickly if two or more showers or appliances in the home are using hot water at the same time, or if you have multiple or high-volume shower heads.
Tank water heaters actually lose efficiency over time due to sediment buildup; this can happen even if they are flushed regularly, as recommended. Within a few years, even a routinely flushed tank water heater can lose five or more gallons’ worth of its hot water capacity, which can lead to your hot water not getting hot enough.
Tank water heaters also come with certain safety concerns. Traditional water heaters can leak and even burst with age, which can cause extensive secondary damage. Though they are equipped with safety features, they produce carbon emissions and can also be dangerous in the presence of gas fumes, due to being prone to vapor ignition. Finally, tank water heaters are often called “traditional” for a reason, as the technology behind this type of water heater has not changed much over time.
Tankless Water Heater Pros and Cons
Tankless water heaters don’t heat and store volumes of water. Instead, when cold water is pumped through the tankless water heater, an inner heating element makes the water hot before it flows back out through the home’s water pipes. Tankless water heaters are much smaller than their traditional tank counterparts, and are typically rectangular. Since they are so compact and take up quite a bit less space than tank water heaters, homeowners can have them installed in the attic or garage, in a bedroom or closet or even on an exterior wall if desired.
Tankless water heaters have other pros which have resulted in more homeowners choosing these models in recent years. They have a longer lifespan than tank water heaters, typically lasting 15 to 18 years with annual flushing. Though the hot water produced by a tankless water heater won’t be instantly hot coming out of the tap, since it takes time for the hot water to travel from the heater to the faucet, tankless heaters do supply limitless hot water as long as the tap is turned on. That means that with a tankless water heater, you won’t have to deal with your hot water running out quickly.
Tankless water heaters also come equipped with safety features that can prevent them from flooding your home or producing harmful carbon monoxide. It’s easy to adjust the temperature on a tankless water heater, which is a helpful safety feature in households with young children or seniors.
The primary drawback to tankless water heaters is their up-front cost. Tankless water heaters typically cost 1.5 to 2.5 times more than tank water heaters to purchase and install, in part because installing a tankless water heater in an older home requires retrofitting to accommodate the new system. If you have a new home, the cost of a tankless water heater may be lower. In some cases, local utility companies provide rebates that can defray these initial costs.
Some people try to save on the cost of a new water heater by purchasing it themselves from a home improvement store and then hiring a plumber to install it, but this strategy can backfire. What many homeowners don’t realize is that water heaters available at home improvement stores can be lower in quality than those available from an installer; in most cases, it’s better to purchase the higher-quality water heater from the installer who will then properly place it in the desired location in your home.
Since each home is unique, as are the hot water needs of the people living in the home, it’s a good idea to contact a plumber for expert advice on what type of water heater might be best for your particular home and needs. A professional can make the most accurate calculations regarding your water usage to determine the hot water capacity you’ll need, and can install the water heater for you, saving you the labor and trouble of trying to do it yourself.
Although you should rely on a licensed specialist for your water heater installation needs, it’s never a bad idea to get an understanding of what factors are taken into consideration when determining what size water heater you should purchase.
What Size Water Heater Do I Need?
Whether you’re going to have a tank or tankless water heater installed, the capacity of the water heater will be figured based on the number of bedrooms in the home. If you’re getting a traditional tank water heater, a 40- to 50-gallon water heater should cover you if you have a two-bedroom home, while a home with three to four bedrooms will need a 75-gallon heater. In homes with even more bedrooms, multiple tank water heaters may be needed.
If you’re going with tankless, the sizing of the tankless water heater will be in terms of how many gallons of water it can heat per minute (GPM). A single tankless water heater will have a gallons-per-minute capability of anywhere from 5 to 11.5 GPM. A 5 GPM tankless water heater should serve a one-bedroom, one-bath home adequately, while a three- to four-bedroom home will need an 11.5-GPM heater. A home with more than four bedrooms may need multiple tankless water heaters to be installed.
A professional plumber can advise you on which size and model of water heater will be the best match for your home based on the number of bedrooms as well as your unique water use needs. Keep in mind that the water heater size should always be based on the number of bedrooms in the home, regardless of how many people actually live there or what their daily hot water needs may be, in order to preserve the home’s resale value.
When considering making the switch from a traditional water heater to a tankless water heater, many homeowners want to know about the potential problems they may come across. While you may be familiar with problems associated with traditional water heaters, you may ask yourself: what are some of the more common tankless water heater issues?
Common Tankless Water Heater Problems
Tankless water heaters are a newer technology and some homeowners are understandably hesitant to make the switch from a traditional tank water heater to a tankless one. There are certain tankless water heater problems to be aware of during the decision-making process, so you can make an informed choice about whether to switch to tankless or replace your old water heater with another traditional tank model.
When a new tankless water heater is installed, it must be properly vented, and the gas lines will need to be the right size. That means that if the unit isn’t installed correctly, the water heater won’t be able to function properly. This is why it’s best to have a licensed plumber install your tankless water heater.
Sometimes, tankless water heaters also run hot and cold if there is a crossover in the plumbing system, if the flow sensor is damaged or if the filter on the cold water inlet is dirty. Tankless water heater problems can also result from corrosion that develops in the lines or from hard water mineral deposits that build up over time if the unit isn’t flushed once a year. Fortunately, this problem can easily be avoided if you contact a licensed plumber to flush your water heater annually. A specialist will also be able to determine if there are any other plumbing problems with your water heater, so small problems can be remedied before they turn into larger headaches.
ABC Can Help With All of Your Water Heater Needs
Purchasing a new water heater can feel overwhelming. Fortunately, ABC Home & Commercial Services has licensed plumbers who can give you honest advice on which water heater will work best for your home’s needs. Once you have decide what type of water heater you’d like to purchase, we can get a new water heater installed for you, so you will no longer have to deal with no hot water in your home or any other common issues associated with these appliances.