What is a gas boiler replacement?

A gas boiler replacement means removing your old gas boiler and fitting a new, high-efficiency condensing gas boiler, connected safely to your gas supply, heating and hot water. Because it’s gas work, it must be carried out and certified by a Registered Gas Installer. That’s not a nice-to-have. It’s the law.
Gas boilers in Irish homes run on one of two fuels:

Natural gas, piped to homes in towns on the gas network.

LPG, or liquefied petroleum gas, stored in a tank or cylinders on site. It’s the usual choice for rural homes that want gas but have no mains supply.
The boiler itself works the same way on either fuel, but the burner, settings and supply are set up for one or the other. A replacement is usually like-for-like, natural gas for natural gas or LPG for LPG, though it’s also a good time to rethink the type of boiler you have.
Most older gas boilers still in use are non-condensing. They send a lot of heat straight out the flue. A modern condensing boiler captures much of that heat and puts it back into your heating, so it burns less gas to keep the house just as warm. The building regulations set high efficiency standards for replacement boilers, and in practice that means a condensing model.
A good gas boiler replacement covers more than the boiler. It includes checking the gas supply pipework, the flue and the ventilation, cleaning out the heating system, fitting proper controls, and testing everything for safety before the job is signed off.
Gas boilers need regular attention, and when an old one starts failing, replacing it is often better value than patching it up again and again. If you’re on oil and thinking about switching, or wondering about a boiler replacement more generally, we can talk you through those options too.
For some homes, especially new builds and deep retrofits, an air-to-water heat pump may be the better long-term choice. We’ll tell you honestly which suits your house.
If your gas boiler is getting old or unreliable, ring us and we’ll take a look.

How does a gas boiler replacement actually work?
A gas boiler replacement follows a careful sequence: survey, choose the boiler, make the gas supply safe, remove the old unit, fit and connect the new one, clean the system, then test and certify everything before you get your heating back. Gas safety runs through every step.
Here’s how the job usually goes:

Survey. We check your current boiler, the gas pipework, the meter or LPG supply, the flue, the ventilation, the radiators and how you use hot water.

Choosing the boiler. We recommend the right type and size for your house. A boiler that’s too powerful wastes gas and wears out sooner.

Isolating the gas. Before anything is disconnected, the gas supply is safely shut off and the system drained.

Removing the old boiler. The old unit and, where needed, the old flue are taken out.

Fitting the new boiler. The new boiler goes up, with a flue that meets today’s rules and a condensate pipe to carry away the small amount of water condensing boilers produce.

Gas connection. The new boiler is connected to the gas supply. The pipework is checked for size and soundness.

Cleaning the system. Old heating systems hold sludge and scale. Flushing it out protects the new boiler and helps radiators heat evenly. A filter is often fitted to keep it clean.

Controls. Thermostats and timers are fitted or upgraded so you can manage your heating properly.

Testing and commissioning. The installer checks for gas tightness, measures the combustion, confirms the flue is working, and sets the boiler to run safely and efficiently.

Certification and handover. As a Registered Gas Installer, the installer completes the paperwork the law requires, and you’re shown how to use the boiler and controls.
Most new boilers go in the same spot as the old one, which keeps the job simpler. Moving a boiler can make sense, for example to free up a kitchen wall or tidy a utility room, but it adds pipework and flue work.
If your hot water cylinder is old, it’s worth thinking about replacing it at the same time. A new hot water cylinder with a new boiler gives you quicker, more reliable hot water. On the other hand, if you’re switching to a combi, the cylinder comes out altogether.
We carry out gas boiler replacements across Athlone, Roscommon and the surrounding area. Give us a call and we’ll walk you through what your job would involve.

What types of gas boiler are available?

The main types of gas boiler are combi, system and regular boilers, and each one handles hot water in a different way. All new gas boilers are condensing boilers, and each type can run on natural gas or LPG once set up for it.
Combi boilers:
A combi heats water straight from the mains as you use it, with no hot water cylinder. They save space and suit smaller homes with one bathroom. The downside is that they can struggle when two showers or taps run at once, and the flow depends on your mains water pressure.
System boilers:
A system boiler heats a separate hot water cylinder, but most of the parts are built into the boiler. There’s no tank in the attic. They suit homes with more than one bathroom, where several people need hot water at the same time.
Regular boilers:
Also called heat-only or conventional boilers, these work with a hot water cylinder and a cold water tank in the attic. They’re common in older homes. If your system is set up this way and works well, a new regular boiler can be a straight swap with little change.
Natural gas or LPG?

Natural gas comes through the mains network and is metered. It’s convenient, with no deliveries to manage.

LPG is stored in a tank or cylinders and delivered by a supplier. It gives rural homes the benefits of a gas boiler where there’s no mains supply.
Size and output:
Boilers are rated by output. The right size depends on the house, the number of radiators and your hot water needs. Bigger is not better. An oversized boiler cycles on and off, wastes gas and wears out faster.
Controls:
Modern controls, from programmable thermostats to smart controls, help you heat the house only when you need it.
Changing type:
A replacement is a good time to ask whether your current type still suits you. A growing family might outgrow a combi. A couple in a bigger house might prefer a system boiler with a cylinder for steadier hot water.
For some homes, a gas boiler isn’t the best long-term answer. In a new build or a well-insulated house, an air-to-water heat pump paired with underfloor heating may suit you better. We’ll tell you straight which option fits your house and why.
Not sure what you have now? Ring us and we’ll work it out with you.

What makes a gas boiler replacement different from other plumbing, heating and renewable energy services?
A gas boiler replacement is different because it combines heating work with regulated gas work, so it carries legal and safety duties that most plumbing and heating jobs don’t. Only a Registered Gas Installer can do it, and the work has to be certified before you use the boiler.
Here’s how it compares with other jobs:

•     General plumbing, like fixing a leak or fitting a sink, has no gas involved and no certification requirement.

•     An oil boiler replacement involves a fuel-burning appliance too, but oil has its own tank, supply line and burner setup, and isn’t covered by the gas registration scheme.

•     A heat pump burns nothing at all. It brings its own design challenges, but no gas safety work.

•     A boiler service keeps an existing boiler safe and efficient, but doesn’t change it.
Gas brings particular risks. A leak can cause a fire or explosion. A poorly fitted flue or a badly set burner can produce carbon monoxide. That’s why gas work in Ireland is restricted to registered installers who are trained, assessed and inspected. You can check any installer’s registration on the Register of Gas Installers of Ireland website.
A gas boiler replacement is also different from a first-time gas installation. A replacement uses an existing gas supply and usually keeps much of the pipework. A new installation, or switching from oil to gas, involves a new supply, possibly a new meter or LPG tank, and more planning.
It differs from an oil boiler swap in practical ways too. Gas boilers are often wall-hung and compact, and there’s no oil tank to inspect or replace. On the other hand, gas pipework sizes, meter capacity and flue position all need checking against current standards.
And compared with a heat pump, a gas boiler is quicker to fit and cheaper up front, and it works well with most existing radiators. A heat pump is a bigger job with lower carbon. Which one suits you depends on your house, your budget and your plans.
What doesn’t change is the need for honest advice. We’ll tell you whether your gas boiler needs replacing, or whether a repair or service would do. If you’re in Roscommon or nearby, ring us and we’ll talk it through.

What should homeowners know before starting a gas boiler replacement?

Before a gas boiler replacement, you should know that the work must be done by a Registered Gas Installer, that the flue and gas supply may need upgrading, and that the type and size of boiler should be matched to your home. A little planning up front makes the job go smoothly.
Here’s what to think about.
Use a Registered Gas Installer. It’s a legal requirement for any gas work. Ask to see their registration and make sure you get the certification at the end of the job.
•     Check the flue position. Flue rules set how close a flue can be to windows, doors and boundaries. An older flue may not meet today’s standards, so it may need to move or be replaced.
•     Look at the gas supply. A new boiler may need a different gas pipe size from the meter. On LPG, the tank, regulator and supply line should be checked as well.
•     Choose the right type. Think about how many bathrooms you have and how much hot water you use. That decides whether a combi, system or regular boiler suits you.
•     Plan the condensate pipe. Condensing boilers produce a little water, which needs a proper drain. Pipes run outside should be protected so they don’t freeze in winter.
•     Clean the system. Fitting a new boiler to sludge-filled pipework shortens its life and can void the warranty. A clean-out and a magnetic filter are usually worth it.
•     Think about the cylinder. If you’re keeping a cylinder, check its condition. An old, poorly insulated one can undo the benefit of a new boiler.
•     Upgrade your controls. Good controls help you use less gas. Check the Sustainable Energy Authority of Ireland website for any current schemes that support heating controls upgrades.
•     Fit a carbon monoxide alarm. Every home with a gas boiler should have a working CO alarm, ideally in the room with the boiler.
•     Time it well. Replacing a boiler in late spring or summer, before it fails, is far easier than doing it in the middle of a cold snap.
•     Keep your paperwork. Warranties usually depend on the boiler being registered and serviced every year.
If you’re considering a bigger change, like an extension with underfloor heating, mention it early so the boiler is sized with that in mind. If you’re planning a gas boiler replacement in Longford or Roscommon, give us a call..

How much does a gas boiler replacement cost in Roscommon?

In Roscommon, a typical gas boiler replacement costs between €3,000 and €4,000 for a standard job, where a new condensing boiler replaces the old one in the same spot on an existing gas supply. Your price within that range depends on the boiler and on what else the job needs.
Here’s what moves the price:

Boiler type. Combi, system and regular boilers are priced differently. Switching from one type to another adds pipework and time.

Output. A bigger house with more radiators needs a larger boiler.

Natural gas or LPG. Both are covered, but LPG jobs may need checks or work on the tank, regulator and supply.

Flue. A new flue, or moving the flue to meet today’s rules, adds to the cost.

Gas pipework. If the pipe from the meter is too small for the new boiler, it needs upsizing.

Moving the boiler. Fitting in the same place is cheapest. A new location adds gas, water and flue work.

System condition. Heavy sludge may need a thorough clean before the new boiler is connected.

Controls. Upgraded thermostats and timers are a small extra that helps cut gas use.

Hot water cylinder. Replacing the cylinder at the same time is priced separately.

Brand and warranty. Different makes and warranty lengths carry different prices.
Switching to gas:
Converting from oil to gas, or connecting to gas for the first time, is a bigger job. It can involve a new connection or an LPG tank, new pipework and removing the oil tank. That costs more than a straight swap, and we’ll price it after a site visit.
Grants:
New gas boilers don’t usually qualify for SEAI grants, which focus on heat pumps and insulation. Support for heating controls has been available at times, so it’s worth checking what’s open when you plan the job.
Running costs:
A new condensing boiler uses noticeably less gas than an old non-condensing one to heat the same house. Over time, lower bills and fewer repairs help offset the cost.
Gas or heat pump?
An air-to-water heat pump costs more up front but can be cheaper to run in a well-insulated home. If you’re unsure, we’ll lay out both options honestly.
Every home is different, so a fixed price over the phone wouldn’t be fair to you. A quick call and a short site visit is all it takes to get an accurate figure for your home in Roscommon or nearby.

What are good brands for a gas boiler replacement?

Good gas boiler brands are the ones with a strong reliability record, solid warranties, parts that are easy to get in Ireland, and engineers who know them well. Well-known names here include Vaillant, Worcester Bosch, Baxi and Ideal, among others. Each has its strengths, and the best choice depends on your house and your hot water needs.
Here’s what to look for:

•     Reliability. A boiler with a good track record in Irish homes saves you hassle and repair bills.

•     Parts in Ireland. If something fails in winter, you want the part quickly, not shipped from abroad.

•     Warranty. Check how long it lasts and what’s needed to keep it valid. Most depend on proper installation, registration and yearly servicing.

•     Efficiency. All new gas boilers are condensing, but some models perform better than others at the lower temperatures that save the most gas.

LPG compatibility. If you’re on LPG, make sure the model is approved for it and set up correctly.

•     Hot water performance. For combis, check the flow rate. A higher flow suits busier households.

•     Size and fit. Compact models suit kitchens and small utility rooms. Some ranges offer more output options than others.

•     Controls. Clear, simple controls, and compatibility with smart thermostats if you want them.

•     Noise. Modern boilers are quiet, but it’s worth checking if the boiler will sit near a bedroom.
A word on price. A cheap boiler from an unfamiliar maker can look like a bargain. If parts are scarce or support is poor, it can end up costing more.
The brand is only part of the story. A good boiler fitted badly, oversized, or connected to a dirty system will disappoint. A mid-range boiler, sized correctly, fitted on a clean system and set up properly, will often outperform a premium one fitted poorly.
The cylinder matters too. If you’re keeping a separate cylinder, a modern hot water cylinder matched to the boiler makes a real difference to hot water recovery.
When comparing quotes, ask each installer why they’ve chosen that boiler for your house. A good installer will give you a clear reason, not just a price.
If you’re weighing up brands for a home in Athlone, Roscommon or nearby, ring us and we’ll talk you through the options that suit your house.