The Differences Between Standard and Tankless Water Heaters

standard water heater vs tankless water heater

If you’re in the market for a water heater, it might be really helpful to know what some of your options are before making the decision to buy. Many homeowners recognize there are differences in system efficiencies, but many don’t know there are two main types of water heater: tanked and tankless. Here, we’ll look at the differences between the two, plus the benefits and drawbacks to a tankless system versus a standard tanked water heater. 


The reason your tanked water heater runs out of hot water after the first couple of showers is because the water heater often cannot keep up with supply versus the demand put upon it. If you have a 50-60 gallon water heater capacity, which is the recommended size for a household of 3-4 people, and you have houseguests, for example, there simply isn’t enough hot water in the tank to supply the demand. On the other hand, the tankless system instantly supplies what is demanded. Water is heated on demand so it doesn’t rely on storage capacity to provide you with hot water.

However, tankless water heaters come in various capacities as well. So, if you consistently, simultaneously run the dishwasher, clothes washer, and shower at the same time, or, if you have a lot of people living in your home who would all use hot water at the same time, it is possible that a smaller capacity tankless water heater might not be able to keep up with demand. So, consider your needs before deciding on the size of the tankless water heater you need. If you’re not sure what would be the best fit, a licensed plumber should be able to help answer all of your questions for you.


One of the inherent risks to a tanked water heater system is the risk of catastrophic failure. Water heaters of this variety can fail in any number of ways, some of them spectacular. Because water expands as it heats, water heater tanks have been known to rupture or even explode if the safety valve fails to release the pressure inside. They are also prone to rusting and cracking or the seals failing, which can lead to leaking or flooding. Any of these failures can cause mold growth and/or water damage to walls, drywall, floors, and baseboards, let alone anything that might have been stored around the water heater. If your water heater is stored in a second story location, it could also damage ceilings, floorboards, main floor walls, etc. However, millions of homeowners have been able to successfully live symbiotically with their water heaters for years without any trouble. Most of this is dependent on how regularly the water heater is checked and maintained. While a neglected and unmaintained tankless water heater can develop leaks and problematic buildup, it doesn’t carry the same risk of catastrophic failure.


A tanked water heater requires regular monitoring. Generally, people will change the temperature settings on their tanked water heaters to prevent scalding or will turn it down in the summer, for example, when demand for hot water is lower. Additionally, it is advised that homeowners turn the water heater down or off if the home will be vacant for a period of time, such as leaving on a vacation. Not only is this a preventative measure against a water heater failure while occupants are away from the home, it also serves to save a lot of money in wasted resources--ie, heating water that won’t be used. You don’t have to monitor a tankless water heater in these ways because it is an on-demand system versus a storage system.


Any water heater must be regularly checked and maintained to prevent damage or failure. With both types, you can expect yearly tune-ups to make sure all the components are working properly and to check sediment build-up to see if you’re due for a clean out. With the tanked heater, a full flush means emptying the tank to get rid of sediment and with a tankless heater, it means pumping water and a vinegar/descaling solution through the system to break down any hard water buildup. Water heater maintenance and check-ups can be performed by any water heater owner who has a basic working knowledge of what to do and what to look for. However, most people are more comfortable having a certified plumber come and perform the maintenance for them, particularly in the case of standard water heaters, since there are many, many components to check and tens of gallons that could be accidentally set loose in the home.


Because the tankless water heater is built to function on demand, it is about 30-50% more efficient than its tanked counterpart. If you think about a standard water heater, it always has a tank of water it needs to keep at a certain warmth. Despite the tank being insulated, if your water heater is in your basement, that means your water heater is constantly working to keep that tank hot. There aren’t such inefficiencies with a tankless system, meaning you could save hundreds to thousands of dollars over the life of the water heater in what would otherwise be wasted energy.


A standard water heater will last you 8-15 years, depending on how regularly it is maintained and how hard your home’s water is. Here in Utah where the water is very hard, without soft water and without regular maintenance, tank water heaters have been known to die in as few as 5 years. On the other hand, tankless water heaters will last between 20 and 30 years with regular maintenance. It is important to note here that in either case, the life of both systems can be shortened or lengthened depending on how regularly the water heater is maintained.

7.   COST

You can look at the cost of a tankless versus a standard water heater in two terms. On the one hand, there is no question that a tankless water heater is more expensive up front than a regular one. Also, if you are upgrading to a tankless water heater from a standard one, installation can be costly because you would need to relocate your existing piping to fit the new system. On the other hand, when you also consider that the tankless system is much more efficient, it can save you money on utilities year after year. Additionally, tankless systems last around twice as long, saving you in replacement costs.

8.   SPACE

If saving space is a big consideration for you, going tankless could free up some valuable room. Because there is no tank and because a tankless water heater mounts to the wall, you can save big on storage space. However, if you have a designated space for the water heater where a tank isn’t taking living or storage space from your family, this might not be a compelling reason to consider replacement.

In the end, choosing the right water heater system for your home requires a lot of consideration. If you have additional questions about whether a tanked or tankless water heater is the right choice for your home and situation, call a plumber you trust. They should be able to take a look at your current system and give you the best recommendation. If you don’t know a plumber and you’re in the Utah area, give Any Hour Services a call!


Author: Amber Smith-Johnson
Copyright © 2019 by Any Hour Services


Jun 24th 2019

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