Glow-worm Energy LPG combi boiler review

The Glow-worm Energy LPG combi boiler is ideal for caravans and houses that aren’t connected to the mains gas supply. (Image credit: Glow-worm)

Glow-worm has been producing boilers since 1934 and is one of the UK’s most trusted boiler brands with a 4.6-star rating on Trustpilot. Glow-worm was acquired by one of Europe’s largest and most trusted heating appliance brands, Vaillant, in 2001. This has enabled the company to extend and develop its product offering in recent years. Its combi boilers are still locally manufactured in Belper, UK.

The Glow-worm Energy LPG combi boiler has been discontinued, but there may be some units available on the second-hand or ex-display market. It should be noted that a second-hand boiler will not come with any kind of warranty, so if it fails soon after you install it you’ll end up paying for another boiler out of pocket. There is no way to test a second-hand boiler before you install it, so you could be taking a huge risk by doing so. Second-hand combi boilers are also hard to find simply because most people don’t replace their boiler unless it has reached the end of its life or stopped working properly. While you can save money on the unit itself by buying a second-hand boiler, the installation cost will be the same as a new unit.

After contacting Vaillant’s customer care team, we confirmed that any Glow-worm Energy LPG combi boilers installed before they were discontinued will still be covered under the standard warranty, as long as they were installed by a Gas Safe engineer within six months of despatch from the Glow-worm warehouse. 

The Glow-worm Energy LPG combi boiler offers a 30kW output, with a modern design and easy-to-use interface. It’s A-rated and uses an automotive-grade aluminium heat exchanger. Lightweight and compact, with an inbuilt filling loop, this boiler is easy to maintain, install and top up.

The dedicated LPG model comes factory-set and ready to install, with no adjustments required. The boiler and flue pack come complete with a compatible horizontal flue kit. The boiler is also compatible with a range of smart thermostats from Glow-worm so that you can control your boiler via an app from any location. This could help you reduce your energy usage.

If you need an A-rated LPG boiler for your home, the Glow-worm Energy LPG is a good choice.

The 30kW Glow-worm Energy LPG combi boiler is available in three bespoke packs supplied with top, rear or vertical flue options for easy installation. The unit measures 700mm (h) x 390mm (w) x 280mm (d), so it’s very compact and easy to install. Horizontal sitting means the boiler can fit more discreetly in your home. The Energy LPG’s high-quality brass body improves performance and a composite front section removes unnecessary weight. It’s also easy to disassemble, which enables faster servicing.

This boiler features a high-grade aluminium heat exchanger which is designed to be long-lasting and heat water more efficiently. The boiler’s modulating Grundfos pump adapts to your hot water demands. The boiler is also Quiet Mark-accredited and able to work with a range of intelligent Glow-worm add-ons, like the Power System Filter.

• Guarantee options: Seven-year standard guarantee. 10 years when installed with a Glow-worm Power System Filter and registered through Club Energy.
• Price range: £1,787 to £2,287
• Efficiency rating: A
• Output rating: 30kW

• Highlights: Compact size and easy to install. Features a Grundfos high-efficiency pump which adjusts to heating and hot water demands, plus a long-lasting aluminium heat exchanger.
• Key benefit: The Glow-worm Energy LPG combi boiler is compact and energy efficient, which makes it great for heating small spaces.
• Fuel: Liquid petroleum gas (LPG).
• Flow rate: 12.4 litres/minute.

A boiler is always a big investment, so consider the options carefully before making a final decision.

Here’s are the pros of buying a Glow-worm Energy LPG combi boiler:

• Compact: The Glow-worm Energy LPG combi boiler provides great sitting options and is small enough to fit into a cupboard, measuring just 700mm (h) x 390mm (w) x 280mm (d ).
• Efficiency: The Glow-worm Energy LPG combi boiler features a Grundfos high-efficiency pump that modulates energy consumption in times of low demand to reduce your energy usage. 
• Heat exchanger: An automotive-grade heat exchanger is designed for longevity and reliability.
• Display: Each unit is fitted with a simple, modern LCD display that makes it easy to change the settings and monitor the performance of your boiler.
• No mains gas needed: The Glow-worm Energy LPG combi boiler doesn’t need a mains connection to operate, which makes it ideal for caravans or holiday homes or rural homes that are very isolated. 
• Smart controls: It can connect to a range of smart controls, like the MIGo smart thermostat, Climastat and Climapro. These controls enable you to monitor and manage your boiler remotely, via an app.

The Glow-worm Energy LPG does have some drawbacks, including:

• Higher fuel cost: The unit price per kWh of energy is higher for LPG than natural gas and oil.
• Customisation: You can choose between horizontal, vertical and rear telescopic flue packs, but no bends or extensions are permitted.
• Discontinuation: Unfortunately this boiler has been discontinued, although it’s still available on the second-hand market.

The Glow-worm Energy LPG combi boiler heats water on demand from the mains, eliminating the need for an external water tank. (Image credit: Glow-worm)

A liquified petroleum gas (LPG) boiler is suitable for homes that don’t have access to a standard gas mains connection. It’s similar to an oil boiler but burns LPG, so it can be filled up using containers. It’s a solid option for caravans, unfinished homes or very rural locations.

Very few boilers are designed for anything except a constant source of power, which is why LPG boilers are a convenient and safe option. You can easily get hold of LPG in safe containers, so you can keep your boiler fuelled depending on your requirements.

As a combi boiler the Glow Worm Energy LPG Combi boiler doesn’t require a hot water storage tank but instead supplies hot water directly to your taps or radiators. This means that the boiler supplies hot water on demand, so you only pay for what you use. These boilers are more compact and portable than conventional boilers and can be moved around as needed.

There are a few good LPG combi boilers on the market to consider.

Viessmann produces fantastic LPG combi boilers with high efficiencies. The Viessmann Vitodens 200-W LPG combi boiler is a wall-mounted boiler with a very quiet operation (34 decibels, compared to the 51 decibels of the Glow-worm Energy LPG) and efficiencies of up to 98%. It’s also available as a gas condensing unit. Both come with 10-year warranty, but the Viessman’s starting price is much higher at around £1,200 for just the boiler unit. 

Glow-worm’s parent company, Vaillant, also offers good LPG boilers with high flow rates and compact designs. Valiant has a slight edge over Glow-worm as its heat exchangers are made from stainless steel, which is more corrosion resistant. The Vaillant ecoTec plus has an output of either 48kW and a lightweight compact design. 

You may also want to look at the Worcester Bosch Greenstar 2000, Worcester Bosch’s most compact and affordable combi boiler. It’s available in an LPG or gas version. The starting price is lower at £890 but the flow rate is slower as well, at 10.8 l/per minute.

The price of your boiler and installation will vary between suppliers and providers. It’s always a good idea to keep an eye on the web as new deals pop up every day. However, according to online estimates, you should budget the following for a Glow-worm Energy LPG boiler:

The Glow-worm Energy LPG combi boiler only runs on LPG, which comes with its own risks. (Image credit: Adobe)

While LPG is a safe fuel source, it does come with risks (just like oil or natural gas). If your boiler isn’t working as it should, always use a Gas Safety-registered engineer with a Gas Safe Register ID card to check your boiler. Make sure that you have your Glow-worm Energy LPG combi boiler serviced every year. This not only keeps your boiler in peak condition, but it also keeps your warranty valid.

LPG can leak as a gas or liquid, which can explode or damage your health. If you suspect a leak, contact your LPG emergency number immediately and extinguish all naked flames in your home, no matter how small. Keep your windows and doors open.

“The Energy range is Glow-worm’s new flagship ERP A-rated LPG boiler specifically designed for private domestic properties. This dedicated LPG model comes factory set with no adjustments required, and there is a single unit code supplied to make ordering easy. The boiler and flue pack come complete with a compatible top horizontal flue kit. Energy has a wide range of outputs and has a choice of rear or top flues, so you can install it virtually anywhere – including inside a kitchen cupboard. Energy will suit every heating demand from most house types and systems requirements.”

• Plumb Nation

“The Glow-worm Energy combi boiler range is a fantastic medium-budget boiler which comes with a great warranty. It’s easy to install and commission, and the rear exit flue can be a real game changer. Highly recommend this boiler for landlords and homeowners.”

• Gatwick Heating and Plumbing, ToolTalk

“If you are looking for a reliable and affordable name in boiler production, engineered in the UK, this could be the ideal model for you. While Glow-worm is known as more of a budget boiler brand, it shares its production location with its parent company, Vaillant. Due to this, it benefits from Vaillant’s innovations and manufacturing prowess.”

• Boilerhut

“Excellent service to our LPG boiler by a very pleasant service engineer from Glow-worm and would certainly recommend.”

• Pauline, Trustpilot

“Our excellent local installer fitted it; all is well. We look forward to the efficiency and hopefully some cost saving in these current energy problem times and as we approach the colder season.”

• Silverjan, Trustpilot

“Professional, easy and reliable service. The heating engineer turned up when they said, reasonable quote and swift installment. Happy all round.”

Helen, Trustpilot

The Glow-worm Energy LPG combi boiler offers great opportunities for space and energy savings in the home. It’s compact and discreet and installation is easy. With its various flueing options, the Glow-worm Energy LPG can be installed in virtually any space, even a small kitchen cupboard.

It is ideal for caravans and partially completed homes that do not have mains access, which also makes it perfect for homes in isolated rural areas, where service delivery may not be readily available. 

It’s manufactured in Derbyshire in the UK to high standards and is guaranteed for up to 10 years (with terms and conditions applicable). On the downside, this model has been discontinued. While it’s still available on the secondhand market, this may affect your ability to acquire the boiler for your home.

If you don’t have access to mains gas, the Glow-worm Energy LPG combi boiler is a solid, highly efficient option.

To compile our Glow-worm Energy LPG combi boiler review, we read hundreds of customer reviews (Google, Trustpilot and other sites), technical documentation, media articles, and other sources of information. We then rated the Energy LPG against a 100-point scoring system that included the following points:

• The warranty period offered by the brand, for a total of 10 points;
• The overall reputation of the brand based on online reviews, for a total of 15 points;
• Trustpilot reviews, for a total of five points;
• Awards and accolades (eg, Which? Best Buy Awards), for a total of five points;
• Customer service performance, for a total of 10 points;
• The price range, for a total of 15 points;
• Efficiency ratings, for a total of 15 points;
• Installation and maintenance network and reviews, for a total of 15 points; and
• Overall performance (temperature, maximum flow), for a total of 10 points.