Glow-worm Gas Boilers

Glow-worm gas boilers remain a popular, affordable boiler brand choice of many home owners through-out Ireland.

Manufactured at Glow-worms state of the art facility in Derby, England. There range includes attractive boiler replacement options for the domestic heating sector.

Since 2001 Glow-worm is owned by the Vaillant Group, a boiler brand recognised for quality and one of Europe's leading heating companies.

Choose Glow-worm for an energy efficient heating system 

Reduce your fuel bills while you increase your homes efficiency and comfort levels with an energy efficient gas boiler from Glow-worm. These cost-effective reliable gas boilers are an excellent choice for those of us on tighter budgets.  

Benefits of a Glow-worm Boiler 

  • Reduce fuel usage by up to 30% 
  • Value for money 
  • DIN Standard ensuring a quick installation 
  • Increase your home comfort 
  • Energy efficient 

Exceptional Boiler Warranty

With manufacturer's warranties of up to 7 Years available, you can be confident in your investment.

Exceptional Automotive Grade Aluminium Heat Exchanger

Featuring a high-quality automotive grade aluminium heat exchanger and innovative compact design. Added benefits include an excellent range of optional heating controls and even an optional rear flue available on some models. 

The Benefits of Glowworm Gas Boilers;

Ultra Quiet Boilers

The Glow-worm range of gas boilers are some of the quietest boilers available today with an expected decibel level of just 47dB.

Free 7 Year Warranty

Get extra peace of mind with an free warranty of up to 7 years for every Glow-worm condensing gas boiler installed by

Increase Comfort

Upgrading to a Glow-worm condensing gas boiler will increase your home comfort while reducing running costs too.

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Find a Boiler

Read through the different glow-worm boilers available to you as well as the advantages and disadvantages if you require any assistance, Get in Touch.

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Boiler Installation

Upgrade to a High Efficiency Glow-worm Gas Boiler expertly installed by Gasworks, lower cost, quick 1 day Installation. Book your boiler upgrade now!


Glow-worm combi boiler range; 

Never run out of hot water again! Glow-worms range of combination boilers offer a competitive solution for all your heating and hot water needs. 

Glow-worm Combi boilers are simply boilers that heat your home while they also produce instant hot water on demand. They do all this from the same boiler unit and therefore a separate hot water cylinder is not required.  

This can be particularly attractive for smaller homes where space is quite limited. A popular boiler choice for small to mid-sized properties. 

glow-worm energy system boiler

Glow-worm Energy Combi

Available in 25kW, 30kW and 35kW outputs, the Energy boiler is an attractive modern boiler unit with an excellent easy to use control range. 

The sleek compact design combined with optional rear flue, make this lightweight boiler an easy installation in almost any boiler replacement situation.

The Energy gas boiler from glow-worm has also been designed with the industry standard DIN piping layout in mind. This further enhances the ease of installation.  

Perfect for retrofits. Using a robust efficient aluminium heat exchanger with large water ways the Energy gas boiler is designed for the boiler replacement market.

The heat exchanger has a patented 4-sided cooling feature, this reduces thermal stress and increases reliability and lifespan. 

Hot water Flow-rate 10.4ltr/min 12.5ltr/min 14.4ltr/min
Hot water Output 25.7kW 30.6kW 35.7kW
 Heating Output 18.3kW 25.4kW 25.6kW

Kitchen Cupboard Fit (700X390X280)

7-Year Warranty (parts and labour)

Wide range of control options available 

High Efficient aluminium heat exchanger 




Glow-worm Energy Store

Designed for large homes with multiple hot water outlets. The Energy Store 35kW Combi is a high-performance wall hung gas boiler which combines the all the benefits of both a combi and system boiler all in the one. The heat exchanger is high-grade Stainless steel and specifically designed for reliability and efficiency. 

It provides plenty of heating and instant hot water as needed, boasting an excellent flowrate of up to 19.7l/min for limited periods. This superb flow rate is achieved by using two 21 litre highly insulated tanks, which are contained within the boiler housing. This makes the Energy Store 35kW an ideal option for larger homes looking to utilise all the benefits associated with combination boilers, while maintaining performance levels.  

Natural gas and LPG compatible, every installation includes a full Glow-worm 7 Year warranty. Compatible with a choice of intelligent controls and accessories from Glow-worm.  

Energy Store 35kW Combi 35kW
Hot water Flow-rate 19.7ltr/min
Hot water Output 35.7kW
Heating Output 30.0kW

7-Year Warranty (parts and labour)

Stainless Steel Heat Exchanger

Wide range of control options available 

Excellent Flow-rate 19.7ltr/min 




Glow-worm System Gas Boilers;

The Glow-worm range of system gas boilers are designed for use on sealed central heating systems. These condensing boilers provide hot water via a hot water cylinder (Hot Press Tank). So are not the same as a combi boiler.  

The system gas boiler is an ideal support solution for solar hot water systems. When correctly installed with the correct controls and components, these condensing gas boilers are quite capable of producing high volumes of hot water for usage. Albeit through a hot water cylinder system. 

Glow-worm condensing boilers are a popular choice for homes throughout Ireland, they offer a full 7-year warranty on the Energy system boiler range. This level of product confidence is quite reassuring. 

glow-worm energy system boiler

Glow-worm Energy System

The most popular Glow-worm boiler, the Energy system comes in multiple outputs from 12kW to 30kW. This size variety offers a home heating solution for a large majority of homes throughout Ireland.  

Compact and lightweight, this smart looking boiler will even fit in a standard cupboard. Optional rear flue further enhances installation suitability, making it a neat replacement option for existing rear flue boilers. 

Highly reliable and covered by Glow-worms 7-year boiler warranty for added peace of mind. 


ENERGY SYSTEM 12kW 15kW 18kW 25kW 30kW
Heating Output 12.3kW 15.2kW 18.3kW 25.4kW 30.5kW


Kitchen Cupboard Fit (700X390X280)

7-Year Warranty (parts and labour)

Lightweight at just under 32 kilograms

High Efficient aluminium heat exchanger 




Glow-worm Ultimate 3

A high quality value for money system gas boiler from Glow-worm, the Ultimate 3 is available in a 25kW output. Designed to meet both heating and hot water demands (Hot water cylinder required) for medium sized homes.

Featuring a high quality robust aluminium heat exchanger, the Ultimate 3 requires simple water flushing during annual servicing. This relatively straightforward approach reduces maintenance costs when compared to other boilers with more intense service requirements.

The Ultimate 3 comes with a 5-year full parts and labour guarantee when installed correctly. Annual maintenance is also a requirement to keep your guarantee valid.


Ultimate 3 25kW System 25kW
Dimensions 740 x 418 x 300
Efficiency 89.7%
Output 25.2kW

5-Year Warranty (parts and labour)

Quiet Operation

Wide range of control options available 





Glow-worm Heat Only Gas Boilers;

Heat only condensing boilers are specifically designed for low pressure open vented heating systems. The majority of older boiler systems within Ireland will be open vented. 

Open vented heating systems can easily be identified by a second smaller water feed tank in the loft space. Hot water will be typically provided by way of a hot water cylinder. 

Glow-worm offer warranties of up to 7 years on their heat only boilers, which have been designed for ease of use and reliability. Unlike the system and combi boiler, the pump, expansion vessel and safety relief valve are not included within the boiler casing.  

Compact sizing and optional rear flue options choosing a Glow-worm regular boiler offers more installation flexibility.  

glow-worm ultimate regular

Glow-worm Energy Heat Only

Attractive, user friendly, choice of controls, value for money and a 7-year warranty. The Glow-worm Energy regular boiler comes in a range of outputs from 12kW up to 30kW.  

Compact and Lightweight the Energy measures just 600mm long, has a depth of only 280mm and is 375mm in width. Optional rear flue gives puts this boiler ahead in terms of installation flexibility. 

The heat exchanger is crafted from a high-performance automotive grade aluminium, which improve both efficiency and reliability.  

Designed for low pressure heating systems the Energy heat only boiler requires only 0.3 bar to operate. Glow-worm also have an excellent choice of control options available. 

MODEL 12kW 15kW 18kW 25kW 30kW
CH Output 12.3kW 15.2kW 18.3kW 25.4kW 30.5kW
Efficiency 89.4% 89.4% 89.4% 89.4% 89.3%


7-Year Warranty (parts and labour)

Kitchen Cupboard Fit (600X375X280)

Wide range of control options available 

High Efficient aluminium heat exchanger 




glow-worm ultimate regular

Glow-worm Energy Store

The Glow-worm Ultimate 25kW boiler is best suited to medium sized homes. Despite its high level of performance, the Glow-worm Ultimate is ultra-quiet during operation. 

 The Ultimate 3 Heat Only Gas Boiler is both compact and lightweight, making installations that bit easier. Featuring an easy to use boiler interface and compatible with a variety of control options give this boiler great flexibility in regards to the homeowners requirements.

Complete with a full 5-year warranty, the Ultimate 25kW gas boiler is an excellent choice when upgrading to an energy efficient condensing boiler.


Dimensions L x W x D 600 x 375 x 280
Efficiency 89.6%
Heating Output 25.2kW

5-Year Warranty (parts and labour)

Designed For Cupboard Fit

Wide range of control options available 




Choosing Your Boiler Controls;

Boiler controls are often overlooked, the correct level of control will minimise running costs and improve both your homes heating performance and Glowworm Boiler Appcomfort level. 

There are a wide range of control options to choose from very basic mechanical timers to fully integrated heating and hot water controls.

The most efficient heating systems will have both load and weather compensation with remote access. 

Advantages of Heating Controls 

  • Increases System Efficiency 
  • Improved Performance 
  • Enhances home comfort 

Glow-worm Gas Boiler Controls 

Glow-worm have a number of different boiler specific control options available. All Glow-worm controls have been designed for ease of use and installation. Unlock the benefits of boiler specific controls and improve both your "BER rating" and home living environment. 


Climapro 1

Straight forward 2 Channel programmable thermostat that gives you the ability to set specific programs for both your central heating and hot water.

•Programmable Room Stat •Load Compensation •Weather Compensation •User Friendly Display •Wireless Version Available •Annual Service Reminder

MiGo App

Get total control of your central heating and hot water with the MiGo programmable room thermostat from Glow-worm. Apple and Android Compatible

• Android and Apple Compatible •Smart yet Straightforward •Multi User Sharing •Energy Consumption Monitor •Self Learning •Load Compensation •Weather Compensation

Climapro 2

Handheld easy to use wireless 2 channel programmable room thermostat complete with wall bracket for secure storage in the chosen primary location.

• Incredibly Easy To Use •Hand Held Portable Thermostat •Load Compensation •Weather Compensation •Easy Wireless Installation •Improves System Efficiency

Weather Sensor

A clever solar powered outdoor weather compensation sensor that communicates with both the Climapro 1 and Climapro 2 wireless thermostats.

• • No Batteries Required •Solar Powered (No need for Direct Sunlight) •Wireless Sensor •Provides Weather Compensation •Climapro 1/2 Compatible •Increases Efficiency

230V Stat

The most basic level of room temperature control, this analogue room thermostat is an easy to use hardwired stat with a clear temperature display.

Easy to Use Wide Temperature range Clear Display

Wiring Centre

The Smart Wiring Centre from Glow-worm delivers an intelligent zoned heating system and is fully compatible with traditional zoned S and Y plan systems.

• Coloured Coded Plug-in connections • Intelligent Hot Water Control • Low Voltage Communication • Neatly Designed • 2 Heating Circuits • Hot Water Circuit

Popular Glow-worm Gas Boiler Questions;

Although Glow-worm is owned by the Vaillant Group the Glow-worm boiler products are a more budget friendly alternative and therefore small differences in boiler quality can be expected.

When correctly installed and maintained you can expect an average lifespan of between 12 and 15 years.

On average, you can expect a Glow-worm boiler to cost between €1795 and €2100 inclusive of installation and vat.

If your boiler is still within the period of warranty Glow-worm can be contacted on 01-6305726. If your boiler is not covered by Glow-worms extended warranty you can contact the Gasworks Team on 01-4433005 or Here

The majority of Glow-worm gas boilers will have an aluminium heat exchanger with the Energy 35 Store boiler being the only Glow-worm boiler with a stainless steel heat exchanger installed by Gasworks.

At least once a year at a minimum, annual servicing is also a requirement to maintain your warranty.


Glow-worm Gas Boiler Guide Prices

Energy System 12kW €1700
Energy System 15kW €1750
Energy System 18kW €1775
Energy System 25kW €1850
Energy System 30kW €1975
Energy Combi 25kW €2075
Energy Combi 30kW €2125
Energy Combi 35kW €2250
Energy Regular 12kW €1700
Energy Regular 15kW €1750
Energy Regular 18kW €1800
Energy Regular 25kW €1850
Energy Regular 30kW €2050
Energy Store 35kW €2550
Ultimate 3 Heat Only 25kW €2050
Ultimate 3 System 25kW €2150