Cover photo for blog and video "Gas Tankless Water Heaters"

Pros and Cons of a Gas Tankless Water Heater

Tankless water heaters are not created equal, and this is especially true when talking about a gas tankless water heater vs an electric tankless water heater. Our discussion today will be specific to the gas tankless variety, while not being model or brand specific. If you’re in the market for a new gas water heater, tankless is surely something you should consider for multiple reasons, but there are certainly some things you should know when making your decision that the commercials and hype don’t tell you. Only you know what’s right for your family and lifestyle so we want to empower you with all of the pros and cons of a gas tankless water heater so you can decide if this is the perfect choice for your home.

PROS 

  • Endless hot water
  • Space Savings
  • Energy Savings
  • Longer lifespan

CONS

  • Requires electricity
  • Mandatory annual maintenance
  • Upgrade investment
  • Needs a condensing unit

The Benefits, in Depth

Endless hot water for many clients is the main motivator to upgrading to a tankless unit. Don’t confuse endless hot water with instant hot water, this is a common misconception. While a tankless water heater instantly heats water on demand it still takes the same amount of time to get the hot water from the unit to the fixture you’re trying to use. The only way to have instant hot water at your fixtures is to upgrade your system with a recirculating pump. Endless hot water means that you will never run out of hot water– you can quite literally take back to back showers all day long and never run out of hot water.

Space Savings we find is the second biggest consideration people have when considering upgrading to a tankless water heater. The size difference and look is dramatically different than a tank style water heater and is perfect for those clients who want to have a sleek look to their water heater while using up a fraction of the space. Gas tankless heaters can also be installed outside which can be a gamechanger for many homes looking to free up space.

Energy savings is also a pro when it comes to converting to a gas tankless water heater. You won’t see dramatic savings as gas is already an affordable energy source but you will see a difference if you are still using the same gallons of hot water vs a traditional gas tank style water heater. Where some of our clients don’t end up enjoying savings on their gas bill is simply because they are taking advantage of the endless hot water and taking those long, luxurious showers they’d always wanted to but couldn’t with a traditional limited tank style water heater.  The average energy rating of a modern energy efficient gas tank style water heater is 96% with a UEF (Uniform Energy Factor) of .86 where a gas tankless water heater runs at 99% efficiency with a UEF of .97, while this difference won’t translate to mind-blowing savings on your gas bill, especially if you end up using more gallons of water than you were before, the tankless unit is more energy efficient than a tank style water heater and can save about 100.00 a year in energy costs on a gallon vs gallon ratio.

Gas tankless units have a longer lifespan than traditional tanks simply because they do not have a tank to leak. Tank style water heaters inevitably over time will leak, the average lifespan that we’ve seen in the last 20+ years here in the Phoenix area is about 7-9 years. Water conditions and maintenance can of course affect the lifespan of your water heater, but the bottom line is the porcelain/glass lining of a tank style water heater will inevitably crack allowing water through and causing the tank to leak. Tankless water heaters don’t face this challenge because they don’t have a tank to leak. While tankless units won’t last forever with proper annual maintenance, 20 years is commonplace for these units and some manufacturers even offer a 15 year warranty on the heat exchanger.

Things to Consider Before Buying 

Gas tankless water heaters, unlike a standard tank, require electricity to work. This isn’t a big deal and for many homeowners– they simply choose to run a quality extension cord to operate the electrical components of the tankless unit, but where this can be a bummer and a CON is if you end up with a power outage for some reason. Without power, the unit will not work.

The other thing you need to consider is the maintenance requirement of a tankless gas water heater. Tankless water heaters with their high demand are magnets to mineral buildup within their components. While all water heaters need to be maintained annually for optimal performance and lifespan, you’re not going to get away with ignoring the maintenance on a tankless unit the way you can with a standard tank style unit. Truly, if you’re not going to commit to maintaining a tankless water heater I recommend you don’t invest in one. The mineral buildup if left unflushed and maintained will quickly fill up your aerators and shower heads with mineral debris and will have to be cleaned out of your fixtures. Flushing and maintaining your tankless unit isn’t incredibly difficult and you can get on our yearly plan to have it flushed and maintained or with a pump (don’t rent a pump, you don’t know where it’s been and you do not want to contaminate your water system) it can be done at home.

What you can expect as a possible CON to upgrading to a tankless gas water heater is the upgrade expense for the initial investment. A gas tankless water heater costs more than a standard tank and it is also more to install due to the custom installation process of each unit and the upgrades required to the venting system. A gas tankless upgrade is often double the price of a 50 gallon gas tank style water heater. Breaking down the lifespans of both water heaters though, this is easily accepted for many when they realize the initial investments nets them double the lifespan so it is like buying two water heaters at once quickly justifying the upgraded expense for those that intend to utilize the tankless water heater for more than 7-9 years finding themselves replacing a standard tank all over again.

The necessity of a condensation line isn’t a con for most installations, but it can be if your water heater is located in a place where running a condensate line proves to be inconvenient and expensive– like a closet in the middle of your home. Gas tankless water heaters that are upgrades from an original tank style installation are condensing units– this type of model is what allows for the conversion of a tank style water heater to a tankless unit without having to make major upgrades to the gas lines. The condensation must have a line to drain through, just like your air conditioner. This condensation line isn’t usually a deal breaker and is often run without difficulty by a licensed professional like Robins Plumbing, Inc. but it can often not be worth the investment if the condensate line is too difficult to run based on the placement of the existing water heater. There are options when it comes to running the condensation line, one of which includes condensation pumps.

Services in Phoenix & Beyond

When you’ve found yourself in need of plumbing services in the Phoenix, Glendale, Scottsdale, or Chandler area, you can trust Robins Plumbing to provide you with prompt and expert care, contact our team today! In addition to our toilet services, we also offer a variety of residential and commercial plumbing services, including: drain cleaning, water heater repair and replacement, sewer camera inspection and locating, backflow prevention, commercial and residential jetting, water treatments, and more. Visit our reviews online to see what others have to say about our local plumbing company!