The Differences between Combi Boilers vs. Conventional Boilers

A lot of research goes into determining what type of boiler system you need for your home. Keep reading to learn about the differences between combi boilers vs. conventional boilers and the advantages that both have to offer.

What Is a Combi Boiler?

A combi boiler is a single unit that eliminates the need for a hot water storage tank. It’s a combination of a water heater and a central heating boiler all in one. Rather than having a preheated stock of hot water waiting to be used, a combi boiler heats up water on demand when you turn on your hot water tap.

How Does a Combi Boiler Work?

A combi boiler uses a series of radiators that are dispersed throughout your home to evenly distribute heat and keep every part of your home at a comfortable temperature. Since combi boilers are always on standby, you can get hot water instantly no matter what part of your home you’re in, whenever you need it. No more having to run the cold water for a few seconds waiting for the water to warm up. The boiler starts working the moment you turn on the hot water tap and provides warm or hot water without delay.

The way it works is that when you turn on the hot water tap in your kitchen or bathroom, the combi boiler’s built-in heat exchanger automatically burns the natural gas and transfers the resulting heat to the cold water. Once the cold water is sufficiently heated, it’s transferred to the hot water tap in your home that activated it. Combi boilers consist of multipurpose interior valves that move in different directions. Some valves are responsible for directing the water flow through the central heating system while the other valves deliver the hot water to the open tap.

Only one of these actions can be carried out at once, but combi boilers allow you to pre-set the thermostat temperature so that the heat distribution throughout your home is comfortably consistent.

What Are the Advantages of Installing a Combi Boiler?

  • Space efficiency.The combi boiler is a single compact all-in-one unit that both heats your home and provides hot water on demand, rather than storing it. Combi boilers don’t require external cold water or hot water tanks and they have a built-in heat exchanger, so they take up a lot less storage space than conventional boilers.
  • Unlimited water supply.Eliminating the need for cold and hot water storage tanks, combi boilers simply source water directly from your water line whenever you need it. You don’t have to wait for cold water to be transferred over to the hot water tank and then distributed throughout your home.
  • Energy efficient.Because the water is only heated as it’s needed, there’s no standby heat loss or waste with combi boiler systems. Not only does this lower your household’s carbon footprint, but it also reduces your energy bills.
  • Affordable and easy installation process. Combi boilers have fewer parts and are easier to install than conventional boiler systems which consist of a cold water tank, a hot water tank, a heat exchanger, and in some cases an expansion tank.
  • Clean and safe drinking water.Combi boilers source drinking and household water directly from your local water supply rather than storing it in a tank until it needs to be used. This makes for cleaner and safer drinking water.

The only real con working against combi boilers is that there’s no backup system. That means if the boiler breaks down or requires maintenance, you’ll be left without hot water until it’s fixed or replaced.

What Is a Conventional Boiler?

Conventional boilers are also commonly referred to as traditional boilers. They’re typically found in older homes that have designated spaces for these types of heating systems. Conventional boilers are heat-only.

How Does a Conventional Boiler Work?

Most conventional boilers have two tanks, one for cold water storage and one for hot water storage. Larger homes may require an additional expansion tank to provide more consistent heat and hot water distribution throughout the property.

The cold water tank sources water from the main water supply and then feeds the cold water into the hot water tank. Whenever the hot water tank is depleted, the cold water tank automatically springs into action and fills it up. The hot water is stored inside the tank until it needs to be used. The water from the hot water tank is distributed throughout the home to keep it at a comfortable warm temperature.

What Are the Advantages of a Conventional Boiler?

  • Hot water storage.You’ll always have a consistent supply of hot water stored, even if there’s a power outage or the boiler system breaks down and needs to be repaired or replaced.
  • Ideal for large households. Multiple people can use hot water at the same time without worrying about running out.
  • Compatible with older heating systems.Conventional boilers are built to be compatible with heating systems found in older homes. If your existing boiler ever needs to be replaced, you should be able to purchase and install a conventional boiler without having to reconfigure the pipework.

Should You Replace Your Conventional Boiler with a Combi Boiler?

There are a few different factors that determine whether or not you should replace your conventional boiler with a combi boiler.

Consider the size of your home, the number of people living in your household, and what your heat and hot water needs are. Conventional boilers are more suitable for larger households in older homes because they can handle higher water consumption demands.

Combi boiler systems are ideal for smaller more modern and energy-conscious households that want to focus on lowering their carbon footprints. Combi boilers are more energy efficient, less expensive to install and maintain, and they take up much less space than conventional boiler units. It’s estimated that installing a combi boiler system for smaller homes can help you lower your energy bill by approximately 40% every year. Of course, that depends on how many people are living in your household.

It’s all about figuring out what your specific needs and priorities are.

Choose MDM Mechanical for Boiler Installation in Hamilton

For more information and for help in deciding whether you should purchase a combi boiler vs. a conventional boiler, speak to a local HVAC expert. MDM Mechanical is always here to help you make the right decision for your hot water and heating needs. We’re a family-owned and operated business that provides boiler installation in Hamilton and surrounding areas. Your search for “boiler specialist near me” ends with us. Contact us today to book a consultation.

About Michael Mead

Michael Mead was born and raised in London, Ontario. He spent 5 years in Calgary, Alberta – and furthered his education in Natural Gas. If Michael isn’t working, he is at home with his son and wife or cooking for a large group of family and friends. Michael is extremely passionate about his business, and is constantly looking for ways to better himself as an employer.

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