Frankly speaking, like any other product in this world, a tankless hot water heater has its own share of pros and cons.
However, I can affirm that the pros beat the cons by a great margin else the tankless hot water heater wouldn’t be so popular as it is nowadays.
Let’s have a quick look at the downsides of a tankless water heater before we dive deep into each one of them.
- High Upfront Cost of the Unit and Installation
- Take Longer to Deliver Hot Water
- Cold Water Sandwich
- Inconsistent Water Temperature When Multiple Outlets Are In Use
- Not So Easy To Achieve A Lukewarm Temperature
- No Access To Hot Water During A Power Outage
But, before that, please allow me to highlight some significant benefits of a tankless hot water heater over a tank-styled heater.
- Small, compact, and sleek designed
- Energy and cost-saving in the long-term
- Unlimited supply of hot water
- Lower risk of leaks and water damage
- Almost zero risks of tank exploding as it doesn’t consist of a tank
- The life expectancy of 15 to 20 years
- No standby heat loss
- Lower risk of burns and exposure to toxic metal
- Equipped with advanced and innovative technology
To begin with, a tankless hot water heater has multiple advantages over a tank-styled water heater.
And, considering all these advantages, I can affirm that investing in a tankless hot water heater would be definitely a great choice, indeed.
But, as an informed buyer, you must be inquisitive to know about the downside of a tankless hot water heater, right?
Without wasting any time on the Jagran, let me get back straight to the main disadvantages of a tankless hot water heater.
Frankly speaking, as per my knowledge and experience, the main disadvantage of a tankless water heater is its upfront cost which involves both buying as well as installation cost.
Needless to say, the upfront cost of a tankless hot water heater is significantly higher than a tank-styled heater.
So, if you’re on a shoestring budget then definitely, you should opt for a tank-styled water heater.
Let’s have a look at some other significant disadvantages of a tankless heater as compared to a tank-styled.
- As compared to a tank-styled water heater, some tankless models can take longer to deliver hot water, that is, the wait time is significantly more
- Moreover, the water temperature is inconsistent when multiple outlets are on significantly
- It becomes difficult for them to provide hot water in case of a power outage
Investing in a tankless hot water heater isn’t an easy decision at all as the upfront cost is significantly high, and is meant to put a dent in your pocket if you belong to a middle-class family as I do.
My suggestion to you would be to spend some time researching and understanding each and every aspect of a tankless heater.
Well, you don’t have to worry at all, I’m here to help you with your queries to the best of my capabilities.
Takes Longer To Deliver Hot Water
Time and again, I’ve highlighted that a tankless heater takes much longer to heat and deliver hot water.
Again, how much would be the wait time totally depends upon the capacity and quality of the tankless model.
As discussed earlier also on this blog, a tankless water heater doesn’t store hot water in a tank in order to keep a supply of hot water ready to flow immediately when you need it.
In fact, when you turn on your faucet or shower, the water in the pipe is cold or at room temperature.
Once you’re done with flushing out the cold water present in the pipe, you’ll start receiving the endless supply of hot water.
But, at the same time, you also need to understand that in the flushing out process, a tangible amount of water gets wasted which is definitely not good for the environment, right?
However, if your faucet is far away from the tankless heater then definitely, it will take some time for the water to travel to the destination through the pipes.
Even the tank-styled heater doesn’t produce hot water instantly rather it has a supply ready to go and doesn’t need to kick on.
In simple words, the hot water reaches the destination (or outlet whatever you prefer to call) quickly.
Cold Water Sandwich
If I’m not wrong then many of you would’ve definitely, come to the term “cold water sandwich” while researching for the tankless heaters, right?
I preferably love to call cold water sandwich a phenomenon in which intermittent use of hot water causes you to feel an initial surge of hot water, followed by cold water, which quickly turns hot again.
The short delay between when the water starts to flow and when the heater kicks on causes a short burst of cold water before turning hot.
Frankly speaking, the cold water sandwich isn’t a major issue but can make you uncomfortable if you’re NOT used to it.
Lack of Consistency in Water Temperature When Multiple Fixtures are in Use
A tankless hot water can deliver as per its maximum flow rate capacity.
So, if your tankless water heater has a flow rate of 8 GPM then it can cater to the hot water requirement of a couple of showers and faucets simultaneously.
But, what if, your tankless water heater has a flow rate of only 3.5 GPM.
Well, in that case, at max your hot water heater would be able to suffice the needs of two fixtures.
In simple words, if you’re running numerous showers simultaneously, then the small and mid-sized tankless heater would find it difficult to cope up with the hot water requirements.
It’s not only the case of a shower only, in fact, depending upon the size of your hot water heater, but you might also run into issues by having a shower and the dishwasher simultaneously.
In case, you’re not aware of what actually the flow rate is, then please allow me to explain it to you.
To be honest, the flow rate is nothing but the amount of water that a tankless unit can heat at a given amount of time.
It’s measured in gallons per minute.
In simple words, the higher the GPM, the more water can be heated at the same time.
I’m attaching a self-explanatory chart for your perusal.
| Outlet | Average Flow Rate (GPM) |
| Bathroom Faucet | .5 – 1.5 |
| Dish Washer | 1 – 1.5 |
| Kitchen Faucet | 1.5 |
| Washing Machine (Clothes) | 1.5 – 3 |
| Shower | 2.5 – 3 |
Tankless water heaters come in different shapes and sizes to caters to the needs of a wide range of household requirements.
Some units are large enough to cater to the needs of a large household.
On the other hand, there are also tankless heaters that are very small and mainly used for a point-of-use purpose.
The under sink heaters are mainly meant to cater to the hot water requirements of one particular sink.
Well, the bottom line is, sizing of the tankless water needs to be done perfectly in the case, you want to reap maximum benefits out of it.
Difficult to Achieve A Lukewarm Temperature
Well, one of the lesser-known downsides of tankless water heaters is that they have difficulty achieving a lukewarm water temperature.
Since a tankless water heater requires a minimum amount of water flow before activation so there is a gap between completely cold water and the coolest warm water that you can create with a hot and cold water mix.
To be honest, though scenarios are rare wherein you wouldn’t be able to reach the desired temperature but they do exist.
Lack of Access to Hot Water During a Power Outage
If you’re a resident of an area wherein storms are quite frequent, then definitely, you should refrain from buying a tankless water heater.
Not only the storm knocks out power in your home but also knocks out the hot water.
As discussed earlier, a tankless hot water heater can be either powered by electricity or gas, and even buying propane tankless water wouldn’t give you relief as it relies on an electric control panel for the operation.
In layman’s terms, regardless of the type of tankless water heater you’ve opted for, you’ll be out of hot water in the power outage scenario.
Wrapping Up
First and foremost, I would like to thank you for being with us till the end.
Secondly, I would like to bring to your notice that we’ve tried to the best of our capabilities to answer your question, what is the downside of a tankless hot water heater.
And, if you’re convinced with our answer, then please do share this piece of information with the ones who are in need of it.
After all, sharing is caring, isn’t it?
Frankly speaking, the benefits overshadow the drawbacks with a huge margin so you can definitely, buy the tankless hot water heater that not only caters to your needs but also falls well within your budget.
That’s all, from my side.
