Compare Boilers vs. Water Heaters to Buy the Best Type

As we compare boilers vs. water heaters and try to understand the differences, many of us find ourselves a bit confused. You’re not alone if you’re attempting to grasp the distinctions between these two essential home systems.

In the following discussion, we’ll explore the unique characteristics and functions of both boilers and water heaters.

Our aim is to illuminate their differences and similarities, helping you determine which option might be the most suitable for your home’s heating and hot water needs, particularly if you’re planning to update your current system.

Boilers vs. Water Heaters: Things to Consider

What are Boilers?

Boilers and water heaters are often confused as being the same thing, but they are not. Yes, they do both heat water, but beyond that, there are big differences.

Boilers are designed to heat non-potable water by using natural gas, propane gas, oil, and electricity as energy sources. The heated water is then delivered to the baseboard or traditional radiators, hydronic floor, or ceiling-mounted systems for space heating. Some boiler types can also produce and use steam for central heating.

Boilers can also heat potable water for your household needs, but indirectly. This is normally done by a heat exchanger running between the boiler and a large water storage tank, heating fresh water for your domestic use. The boiler will fire up when the water temperature drops, so it reheats it to a preset level.

What are Water Heaters?

On the other hand, water heaters are designed to do what it says on the can – heat water. They are not used to power your home heating system; they only heat water and store it in a large tank ready for use.

Depending on your needs, they can be electric, gas, fuel oil, or solar-powered and commonly store between 20 and around 100 gallons of hot water.

So, if you only have a water heater, you will need a separate system to heat your home, like a furnace, boiler, or heat pump, for example, because most water heaters will not do that for you.

Boilers vs. Water Heaters – Comparing Differences

Boiler	Water heater
Water is not safe for human consumption	Water is safe for consumption
Uses hot water or steam to heat the space or potable water	It is used only for water heating
Complex system	Simple controls
It requires a lot of space	Smaller footprint
Expensive	Affordable

Types of Boilers

Boilers come in many different categories and varieties:

• Hot water boilers: Often use a gas or oil burner to heat non-potable water, with pumps circulating the hot water to radiators, baseboards, or hydronic floor systems, where it radiates heat.
• Steam boilers: Designed to heat water and convert it into steam, which is then delivered to radiators using pressure and gravity.
• Standard (conventional) boilers: Require both a cold-water storage tank and a hot water tank, making them space-intensive compared to other types.
• System boilers: Utilize two components: a boiler and a hot water cylinder. Unlike conventional boilers, they do not require a cold-water storage tank, making them simpler to install and more space-efficient. The heated water is stored in the cylinder.
• Combination (combi) boilers: Provide heating for your home and heat water on demand instead of storing it in a large tank. The boiler activates whenever hot water is needed, offering convenience and efficiency.

There are also other options available to you:

• Gas boilers
• Oil boilers
• Electric boilers
• Biomass boilers
• Condensing boilers

Types of Water Heaters

Water heaters are typically divided into several categories:

• Tank-type water heaters: Designed to store and heat potable water exclusively.
• Tankless water heaters: Provide hot water on demand, delivering an endless supply. They are energy-efficient, powerful, and compact, saving valuable space.
• Indirect water heaters: Use a space heating system, such as a furnace or boiler, to heat the water stored in the tank.

The type of a boiler or water heater you will choose depends on many factors, including:

• Your budget
• Available space
• Size of your home, number of occupants, and bathrooms
• Hot water requirements

Boilers vs. Water Heaters: Pros & Cons

Boilers are Ideal for Larger Homes or Multiple Uses

In the debate of boilers vs. water heaters, boilers are particularly well-suited for larger homes with high heating demands. Their ability to simultaneously provide heat and hot water for various uses makes them a practical choice for homes with multiple bathrooms, large families, or properties like apartments and multi-family homes.

Boilers Provide Consistent Heat Distribution

A significant advantage of boilers is their ability to provide uniform heat distribution. Unlike other heating systems that might create hot and cold spots, boilers ensure a consistent temperature throughout the home, enhancing comfort and energy efficiency.

Modern Boilers Offer Flexibility

Modern combination (combi) boilers do not require a hot water storage tank, and they use a heat exchanger built into the boiler to deliver hot water on demand in the same way a tankless water heater does. They are compact in size and efficient at carrying out both home heating and your water heating requirements, so the savings in space and energy make them well worth considering.

Combi boilers and standard boilers are most efficient in cooler climates where your home heating operates longer each year. The reason is, to heat your water during the summer, your boiler has to fire up as water is called for. So, like any boiler-heated water, it’s less efficient in warmer climates.

Water Heaters are Cost-Effective for Smaller Homes

For smaller homes with lower hot water demands, water heaters are an economical choice. They are less expensive to install than boilers and, in the case of tankless models, can significantly reduce energy bills by heating water on demand.

Water Heaters are Simpler

Water heaters, particularly electric models, are simpler in design and operation compared to boilers. This simplicity translates into easier and often less frequent maintenance, making them a user-friendly option for most households.

Water Heaters are Cheaper

The main benefit of standard water heaters is they are cheap to buy, reliable, and, if regularly maintained, will deliver excellent service for between 10 and 15 years.

Additionally, boiler installation can be more expensive due to the complexity of the system.

They also require regular maintenance to ensure efficient operation and prevent breakdowns, which can add to the overall cost of ownership.

Water Heaters are Slimmer

They do take up a reasonable amount of space, but if there has been one fitted to your home previously, the space will have been created when the house was built. Often, they are located in a garage or utility room. Modern water heaters are slimmer and more efficient today than ever before, but they are large, especially if you need the 80-gallon size.

Tankless Water Heaters are Better Option

You could investigate the benefits of tankless water heaters to reduce your energy costs from heating and reheating a large tank of hot water over and over. These units are much more compact, can be installed outside, and have substantially lower energy costs.

However, it is essential to ensure you buy the correct size unit for your home, or you could run out of hot water if the heater is too small for your demands.

The downside is that tankless water heaters are more expensive to buy and install, and they require a certain minimum water pressure to work correctly. They also need filtration, especially if your water source is from a well and in hard water areas; water softening may also be required.

Water Tank Heaters Have Limited Capacity

One downside of water heaters, particularly tank models, is their limited capacity for simultaneous usage. This can be a drawback in larger households where hot water is needed for multiple purposes at the same time.

Additionally, tank water heaters can suffer from standby heat loss, where heat is lost from the stored water, leading to increased energy usage.

Considerations

Reducing Costs

Reducing energy costs, especially for heating and air conditioning, is a priority for most households, as these two alone account for over 50% of power usage in an average home. When evaluating ways to cut these expenses, comparing boilers and water heaters becomes essential, given their significant role in energy consumption.

Energy usage varies based on factors such as location, home size, insulation levels, and the type of energy used. Additionally, 27% of household energy is consumed by water heating, lighting, and refrigeration, which are used year-round. In Canada, energy consumption follows similar patterns but differs by province, emphasizing the importance of optimizing your energy usage to maximize savings.

Assessing Energy Costs and Suppliers

Choosing the right energy supplier is crucial for reducing costs. While you may not want to change the type of energy you use, exploring supplier deals can yield substantial savings. Look out for promotions aimed at new clients, but carefully review the terms to avoid long-term commitments that may not benefit you in the long run. Switching suppliers is often a simple process and can lead to significant reductions in your energy bills.

Selecting the Right System

If you’re in the market for a new boiler or water heater, start by researching available options. Consider what systems your neighbors or family members use and consult a professional to ensure proper sizing. Errors in sizing can lead to inefficiencies and expensive fixes later.

For larger homes, a boiler with a sizeable hot water storage tank may be ideal. While these systems require more space, they efficiently heat both your home and water. If space is limited, a combination (combi) boiler might be a better choice, as it heats your home and provides on-demand hot water without requiring a storage tank.

If you’re opting for a standard water heater tank, prioritize models with the latest energy-efficient features. Carefully evaluate sizing and specifications to ensure they meet your household’s needs.

Installation and Professional Advice

Hiring a qualified professional for installation is crucial. Many suppliers offer full-service packages, including site inspections, system sizing, delivery, installation, and removal of your old unit for safe recycling. These comprehensive services ensure a smooth and hassle-free process.

Considering Tankless Water Heaters

Tankless water heaters are an increasingly popular option due to their substantial energy savings and lack of standby energy losses. However, proper sizing is critical to avoid performance issues later. Consider your household’s hot water needs, including the number of people, bathrooms, and appliances requiring hot water, such as clothes washers and dishwashers.

In some cases, installing additional on-demand heaters for specific areas, like extra bathrooms or laundry rooms, might be necessary. A professional technician can guide you through the sizing and installation process to ensure your unit meets your requirements.

Conclusion

Understanding the differences in boilers vs. water heaters, as well as the unique benefits each offers, is essential for making an informed decision for your home. This knowledge helps in comparing these two systems more effectively.

Your final choice will depend on various personal factors, including your home’s size, energy needs, and family lifestyle. Therefore, seeking professional advice at the initial stages of your project, particularly when considering boilers vs. water heaters, is highly recommended to ensure you make the best decision for your specific situation.