Where should I install my tankless water heating unit?

How to decide the best location for your water heater

This is a question many homeowners purchasing a tankless water heating unit face every single day. And it’s not an easy question to answer, but we’ve got you covered.

Firstly, every manufacturer has their own recommendations for the physical location of a tankless water heating unit. Since every tankless water heating unit is different (unless you’ve got the same models, of course) every instruction manual will say different things. It’s essential that you adhere to what the manufacturers recommendations are, as following them will ensure you receive the maximal functioning of the product, and that includes all sorts of benefits, such as benefiting from absolute maximum efficiency, lowest noise, hottest water and highest safety from pressure accidents.

Their instructions are important, and should never simply be disregarded as unimportant. Always follow the instructions of you manufacturer over anything else, as they know about their product best, and it’s their legal obligation to protect you and your property from damage to a reasonable extent. Seriously, follow their advice.

But – we provide a generic idea of where you should install your tankless water heater, to save you the trouble of having to decide for yourself. Every decision has both positives and negatives, pros and cons, which makes it difficult to actually reach a decision. But that should be no problem anymore.

You’ll find that there is a “direct correlation” between the functioning of the tankless unit and its location. You don’t really want it buried underground or positioned outside where it will freeze up in the winter, but you also don’t want it dangerously hot and exposed to direct sunlight in the hottest of summer months, especially if it’s powered by propane or a similar gas.

Your positioning of your tankless water heating unit will also affect how efficient it is, and how much water and energy gets wasted. For example, positioning your heater nearest to where demand is ensures that it does not need to travel miles to reach the outlet, and therefore it won’t cool in ‘transport’ – in the piping and cables.

What to consider

Firstly – are you strapped for cash?

If you’re on a very tight budget, you likely won’t have too much freedom deciding where to put your new tankless water heating unit. This usually happens because you don’t actually have much freedom to re-wire your gas lines or re-design the layout of your home, and therefore, your only option would be to stick the heater in the position of the previous one.

This may not always be the ideal option, and you may have to accept that you will have to compromise on efficiency. However, you’ll note that you can keep almost everything the same, only you’ll have more space, especially if you’re switching from a traditional, inefficient, tank-based water heating home solution to a more modern, more innovative, more efficient and more effective tankless home water heating solution for the first time.

But if you’re strapped for cash, this will have to be your option. Just stick it where your previous heater was. That way, you’re not messing around with re-designing everything and having to clear space to install a new heater, and all that nonsense.

But what if you have a little bit more to splash, and want to maximize the efficiency of your heater for the long run? Well, many factors come into play, and it won’t just be how much cash you have – is your home even compatible?

Secondly – Is your home compatible with your unit?

Do you know if your water heater can even function in your house? It’s often the case that upon purchasing a tankless water heater, people end up discovering that it’s not functional, because they failed to check their homes before they checked and purchased a tankless water heater.

You may have purchased the most high-quality, most least-faulty, most well-designed tankless water heater and still not have it work for you.

For example, if you have a gas tankless water heater than you have just purchased, but failed to check whether your home is suitable for such a water heater, you may find yourself having to either get a refund for the water heater and be stuck with your old, non-working, rusty and ugly heater, or paying thousands – literally thousands – to do all of your gas piping again, only to make your home compatible.

With electricity, similar can occur. Can your home even provide enough power? There are some water heaters that require literally 100A more power than the average household is able to provide. And that’s not taking into account any other electronics, either. That’s only a water heater.

Always make the decision to check this as soon as you possibly can, and ideally before you commit to purchasing a tankless unit.

Usually, you’ll have to – as above – place your tankless water heater in the same place as your previous water heating system or unit was, if you don’t have the money to move it around where you want it.

This can be incredibly unfortunate, as you may find yourself losing out on efficiency. Always check before buying.

The compatibility of your home can place strict limitations on where you install your new tankless water heating unit.

Thirdly – Can you place it away from ice and ‘the elements?’

If you’re able to keep your water heater in a warm, yet protected place – such as under the stairs – then that would be ideal.

Not only would this prevent your water from freezing up during the winter, but you’ll also not have to hear it’s operation nearly as much as you might if you just placed it in your kitchen. Of course, this is a benefit only if you can afford it. Your gas piping defines all, and without it in the correct positions and layout to accommodate a gas-based water heater, you may struggle. If it’s electric, you should be absolutely fine provided you have a power outlet nearby.

About the author

Steve Bates

Hi, I'm Steve and I currently reside in Chicago, Illinois. Although for most of the last 20 years I was a partner in a HVAC company down in Austin, Texas.

I understand the frustration involved with dealing with water heater repairs and replacing or upgrading to a new, more efficient model.

My aim is offer some basic advice on fixing home hot water systems. And if a repair isn't possible, then to make the process of selecting a new water heater – be it gas or electric - as simple as possible.

So that you can save money and have a safe and reliable hot water system in your home for many years to come.