If you are considering changing to, or need to upgrade your existing tankless water heater, then deciding which style and model of heater to purchase, can be confusing. There’s a lot to think about but, don’t worry, in this article we will help you make the right decision to ensure your household has plenty of hot water available just when you need it.
A tankless or demand-type water heater heats the water when you need it from a small wall mounted tank and then flushes it through to your showers, wash hand basins etc. These can be powered by electric, natural gas or propane. Tankless water heaters require a much smaller amount of space than traditional tank systems and generally last longer and can be more economic to run.
If you are looking for the top tankless water heater then be sure to check out our comprehensive tankless water heater guide here and for further advice on how to figure out which size heater you need than read our article water heater size guide here.
Firstly, here’s a few things to consider when making your decision:
That may seem like a lot of things to consider but don’t worry, we’ll take each one step by step. If you don’t have time to read the whole article, check out this handy chart for a quick round-up.
Note: Although gas is cheaper than electric the efficiency and other costs saving features of electric tend to outweigh the savings of gas over electric.
Gas VS Electric Tankless Water Heater – Comparison Table
|Maintenance||Annual service is advisable to ensure the system is safe.||Very little maintenance required.|
With a tankless or demand-type water heater, you basically have a choice of the following fuels:
In this article we are going to be concentrating on gas and electricity as these are the main fuel types used. If you want to know more about propane tankless water heaters, than check out our other articles.
There are pluses and minuses to using either of these fuels so read on to learn more and see which will be most suited to your home.
Hot Water Requirements / Size
To decide which size tankless water heater, you require you need to know a couple of things:
Both are easy to figure out and knowing them will help you to choose the correct size and model of heater for your home. Purchasing the correct sized heater for your household is vital. It will not only ensure that hot water is available when needed and save your money on the purchase price but, also on the ongoing running costs.
To calculate your households flow rate, you first need to know how many fixtures use hot water you will use simultaneously. So, add up the wash hand basins, sinks, and showers in your home. Don’t forget to add any small washrooms you may have in the basement etc.
To get a picture of how much flow rate you require – work out how many hot water faucets or showers you want to run at the same time. For example, in the morning you may wish to run two showers and the downstairs cloakroom hot water. This then is the amount of hot water you need to have available in your house for your morning routine.
A simple way to work out the flow rate is to place a five-gallon bucket beneath a facet or under a shower. Time how long it takes to fill the bucket, and this is the flow rate of that facet (or shower). For example, if it takes 3 minutes to fill the bucket, then the flow rate = 15 gallons per minutes or 15 gpm. Note this is a guide only, each facet or shower may have a different flow rate. But, it will give you an indication of the average rate within your home.
According to energy.gov gas tends to have a higher flow-rate than electric.
If you have a high flow-rate you can install a low-flow water fixture.
Ground Water Temperature
This varies across the country and of course will alter with the seasons. This map by the Bradley company is a clear and helpful way to identify your regions ground water temperature.
For more information on the choosing the correct size tankless water heater check out our water heater size guide.
Running Cost / Efficiency
In deciding which model, size and fuel type water heater to choose, consider also the Energy Factor.
The energy factor (EF) indicates a water heater’s overall energy efficiency based on the amount of hot water produced per unit of fuel consumed over a typical day. This includes the following:
The higher the energy factor, the more efficient the water heater. However, higher energy factor values don’t always mean lower annual operating costs, especially when you compare fuel sources.’
This helpful information was provided by energy.gov on whose website you’ll find a wealth of useful information on household appliances and how you can save energy around your home.
The price of installation will vary considerably depending on whether you opt to install the heater yourself or use a contractor. It is worth keeping in mind that the correct installation of your heater will ensure it is safe, cost effective and will endure many years of use. Many suppliers will offer an installation service when you make your purchase but, if you need to select a contractor yourself, here are a few pointers:
If you plan on installing the heater yourself than first consult the manufacturers manual for details of the correct installation and to ensure it meets safety requirements etc. You should also consult your city or town officials to ensure any permits needed are obtained before work begins. Check too that you will meet your local water heater installation code (if applicable).
The correct maintenance and servicing of your tankless water heater will not only ensure that it is safe but that it is running efficiently and can help to extend its lifespan both of which will save you money.
As you can see there is a lot to consider when shopping for a new tankless water heater system. Do you opt for electric or gas? They both have their pluses and minuses that’s for sure. A lot will depend on the utilities you have available – if you only have a choice of electric because you don’t have a natural gas supply, it’s simple. But if you have both options then look at the bigger picture taking into account both current and future utility costs, maintenance and your personal preference.
According to energy.gov ‘The average household spends $400-$600 a year on water heating – accounting for 14-18% of homeowners’ utility bills.’ Check out their website for lots of useful hints and tips on how you can lower your water heating (and other) bills.
Here at lahaaland we reccomend buying an electric tankless water heater over a gas one because they are:
Be sure to check out our tankless water heater buyers guide and our top recommendations here.