Gas Boiler Types Explained

It’s no secret that energy and heating costs can sometimes feel like a hefty load to bear for many households. We’re usually on the hunt for the most energy-efficient and wallet-friendly methods to warm our homes.

Have you ever found yourself pondering, “What kind of boiler do I own?” or “What kind of boiler should I invest in?” Well, you’re not alone. These are common thoughts, and we’re here to unravel the enigma of boilers for you.

Knowing Your Boiler

Before we delve deeper, let’s shed some light on your boiler’s lifespan. Boilers, notably top-tier models like the Ideal Logic Max, have a 10 year parts and labour guarantee and an expected lifespan of considerably more than this. When it’s time for a boiler replacement, you’ll need to consider factors like cost, reliability, space, hot water requirements and the size of your home.

You’ve probably come across the term ‘condensing boilers’. It’s mandatory for all Irish homes to have these installed, as they’re significantly more energy efficient than their older counterparts. They ingeniously harness heat that would typically vanish into thin air, meaning less carbon footprint and less strain on your wallet – it’s a win-win!

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Boiler Types: System, Heat Only and Combi

There are three main types of gas boilers found in Irish homes today: System, Heat Only and Combi boilers.

System Boilers: The Main Boiler of Choice

Enter the formidable system boilers. These are now the most frequent boiler installed in the Irish market. They suit most homes are generally the go-to choice where older traditional wall boilers, back boilers or freestanding boilers are being replaced. They include many components of a central heating system within the boiler itself eg pump, safety valve, expansion vessel etc and the lengthy guarantee on your boiler includes these components. This is a great advantage as it eliminates the possible failure of these components on older central heating systems. System boilers operate by heating water in a separate storage cylinder, ensuring they can deliver hot water to multiple bathrooms without impacting your home’s heating.

System boilers, like the robust Ideal Logic Max System Boiler, are also perfect for homes boasting two or more bathrooms. They’re relatively straightforward to install.

Heat Only Boilers: For Larger Homes

Next up, we arrive at heat only boilers. A heat only boiler is a good option for the bigger house, where a larger pump is required to heat more than the average amount of radiators. Like the system boiler, they heat water in a separate hot water cylinder.

Combi Boilers: Compact and Convenient

Enter the Combi boilers, or ‘combination boilers’. These boilers eliminate the need for a separate water cylinder and provide hot water “on demand”. They’re a fantastic space-saving solution, particularly ideal for smaller homes or flats.

Combi boilers, like the sleek and efficient Ideal Logic Combi Boiler, do have their role to play. They’re energy-efficient, and deliver instant hot water – say hello to invigorating power showers! However, they do come with a few limitations. They rely on mains water pressure, so a booster pump has to be installed. Additional pipework changes to take your hot water cylinder off your system are also necessary and both of these factors add to the cost. Also, they may struggle to supply hot water to multiple bathrooms simultaneously.

AllGas Are Here To Advise & Help

By now, you should have gained a good understanding of the type of boiler that’s currently serving your home. If you’re still feeling a tad uncertain, no worries! Don’t hesitate to get in touch with us, and we’d be more than willing to lend a hand.

Let’s remember, the kind of boiler you own significantly influences your home’s energy efficiency and your heating expenses. Opting for a boiler upgrade might seem like a sizeable investment initially, but the savings you’ll pocket on your energy bills can be quite remarkable.

Boilers like the top-notch Ideal Logic Max stand as the stellar choice for Irish households, presenting exceptional energy efficiency and reliability. So, if you’re contemplating a boiler replacement, this model is definitely worth considering.

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Allgas: Your Trusted Ally for a Warmer, Happier Home!

Understanding your boiler is key to making informed decisions about its maintenance, repair, or replacement. And remember, a more efficient boiler doesn’t just keep your home warm and cosy – it also helps you make significant savings on your energy bills while contributing to a greener environment.


Q1: Tell me more about condensing boilers. How are they different from older boilers
A1: Right, so a condensing boiler, let’s think of it as an energy-saver! Unlike the older traditional boilers, these smart devices capture and recycle heat that would otherwise simply escape into the ether. The result? Less fuel, reduced carbon footprint, and savings on your energy bills. These boilers are also often referred to as high efficiency boilers.

Q2: I’m thinking about getting a new boiler. What factors should I keep in mind?
A2: Great question! It’s not just about picking any boiler off the shelf, but finding the right fit for your home. You’ve got to consider cost, reliability, how big your house is, and how much hot water you need. Got a lot of bathrooms or a big family using hot water frequently? A system boiler might be your best bet. Have a considerably larger than average number of radiators? A heat only boiler with separate large pump may be the best option. Living snug in a smaller space? A combination boiler could be your space-saving, hot-water-on-demand champion!

Q3: So, how does a combination boiler provide hot water and heating? I’m curious about the process.
A3: The combination boiler, or ‘combi’, as it’s often called. It’s directly connected to your mains water supply and heats water exactly when you need it. No separate storage hot water cylinder, no waiting around – just hot water on demand. And it doesn’t stop at hot water. These combi boilers double up and keep your home toasty by pumping hot water through your radiator system.

Q4: Can you help me understand where an immersion heater fits in the heating and hot water system of a home?
A4: An electric immersion heater is nestled in your hot water cylinder. When you flip it on, it heats the water in the cylinder, ready to supply hot water when you need it. It can be your primary hot water source but remember, while they are handy, they don’t quite match up to the efficiency of a condensing system or heat only boiler or a combi condensing boiler that provides hot water on demand.