Ultimate Guide to Buying a Water Heater: Tankless vs. Conventional

Posted on: Oct 27, 2022

No one likes being cold, especially during Oklahoma winters. Getting a water heater is a significant decision because it’s not only a big purchase, but you’ll depend on it to warm your home for many years.

Buying a water heater can be overwhelming with all the information you need to know to find the right one for you. That’s why we’ve created this water heater buying guide. Keep reading, so you know what to look for in a water heater. 


What Is a Water Heater?

It’s pretty simple. A water heater is a device designed to heat up water for various household needs like doing dishes, laundry, or taking a shower. Edwin Ruud invented the tank-type modern water heater in Philadelphia in 1889. It wasn’t until the 1970s that tankless water heaters hit the market. You can choose tankless or conventional water heaters, using electricity or gas as fuel.


The Difference Between Tankless and Conventional Water Heaters

The best choice between these two types of heaters will depend on your budget and lifestyle. 



A tankless water heater is also an on-demand heater because it only heats up water when you tell it to through the hot water faucet. The water heater will shut off as soon as you turn off the hot water faucet. 

This type of heater is smaller and uses less energy than a traditional tank water heater. Be aware it doesn’t work well with low or fluctuating demand volumes. The sensors won’t work in these situations either, and you may get cold water when you expect hot. 



Traditional tank water heaters have a storage tank that’s constantly filled with hot water. The idea is that the tank has hot water at the top and takes in cold water at the bottom, so it has time to warm up. This way, you always have hot water.

The tank is cylindrical and glass-lined to prevent corrosion. 

An exhaust system leads to the outside with conventional gas water heaters, so fumes leave your home. A gas water heater can have an automatic electric ignition system or a standing pilot light. 

Conventional electric tanks are heated by two heating elements within the tank. Electric water heaters don’t produce any emissions. 


What to Look For In a Water Heater

You should take your time to decide which water heater you’ll buy. This section of our water heater buying guide offers a few suggestions before buying. 


Size of Heater/Tank

You first need to decide on how big you want your heater to be. If you go with a water heater with a tank, you must consider the tank size. The size of your tank will depend on how many people are in your household. Be aware that larger tanks will cost more.

A typical guideline to follow is:

  • 30 to 40 gallons= one or two people
  • 40 to 50 gallons= two or three people
  • 50 to 60 gallons= three to four people
  • 60 to 80 gallons= five or more people

With tankless models, the size of the heater depends on how many water fixtures are within the house. Consider the average groundwater temperature and how many faucets are expected to be used simultaneously.



Along with the size of the heater, you also must consider available space. If you already have a heater you’re replacing, take measurements of the heater and the surrounding area. 

If you’ve never had a water heater, choose and measure the area you hope the heater will go. Make sure there’s enough space for heat to radiate without damaging anything nearby.


Type of Heater

Once size and space are chosen, it’s time to decide what kind of heater you want. Depending on the area available in your home, this choice may have already been made.


Fuel Source

Your choice of fuel will be the main cost of your heater once everything is installed, except for maintenance or surprise issues. 

If you’re more eco-conscious, you should look for a heater that runs on electricity. Electricity tends to cost more than gas, but there will be no emissions to worry about.

Gas is less expensive than electricity, but you must ensure you have an exhaust system to release vapors for safety.

Both energy sources are useful; it’s really a personal preference.



It’s always good to consider what kind of warranty comes with your heater. Things can happen, and it’s better to be covered than pay for a quick repair or hot water heater replacement. Warranties should at least cover:

  • Parts defects
  • Installation defects
  • A repair or replacement guarantee for a certain number of years


Anti-scale Device

If you go with a tank water heater, ensure it includes an anti-scale device. Minerals break apart in hot water and will sink to the bottom of the tank. This can clog pipes and not allow as much water to stay within the tank. An anti-scale device will help with the issue and extend the heater’s lifespan. 



It’s essential to consider not only monthly fuel costs but installation costs, too. Tankless heaters cost more with installation but have lower monthly costs, while conventional heaters are the opposite.

Consider how much you want to spend upfront and monthly payments. 


Get a Water Heater with Airco Service before Winter

Oklahoma winters can be brutal, so get your heater now instead of later. You shouldn’t choose a water heater quickly; the need will be urgent when it gets cold.

If you’re still feeling overwhelmed after reading our water heater buying guide, then contact us at Airco Service. We’ll help you find the right heater for your home. We also help with hot water heater maintenance and water heater repairs.

Contact Airco Service now for a free estimate on a water heater.