Common Glow-worm Boiler Problems & Repair Advice

Common Glow-worm Boiler Problems & Repair Advice

Glow-worm Boiler Problems and repair advice

If you have an Glow-worm boiler, this guide to the most common problems that you could experience will help you through the hard times and could even see you fixing a fault yourself.

Should you be in any doubt at all or identify a fault that needs an engineer, you can get a free boiler repair quote with our service.

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Who are Glow-worm?

For over 80 years, Glow-worm have been producing heating and energy products to become one of the leading heating manufacturers in the UK. Get to know even more about Glow-worm and their full range of boilers with Boiler Guide.

Top 5 Glow-worm Boiler Problems

  1. Low boiler pressure

    If the pressure gauge on your boiler is showing anything below 1 then you may have an issue which can lead to your central heating system not functioning as well as it should. Use our guide to low boiler pressure to find out even more.

  2. Error code F16

    If F16 displays on your boiler, there’s a flame detection fault with your boiler. This is likely to mean that the probe needs to be cleaned or replaced. Check that the pilot assembly is spotless and free-flowing from the gas valve.

  3. No heat or hot water

    There are many potential reasons why there’s no heating or hot water in your home, including broken diaphragms and airlocks, failure of motorised valves, issues with the thermostat or low water levels. Start out by checking for an issue with the boiler pressure or your thermostat.

  4. Frozen condensate pipe

    A condensate pipe on condensing boilers transports the acidic water, caused by waste gas, away from the boiler. This usually runs outside into a drain so in the colder months being outside can lead to freezing.

  5. Gurgling, banging or whistling noises

    Any strange noises you’re hearing could be caused by a variety of things including air in the system, alternatively the water pressure could be too low or it’s kettling. You might be able to determine the type of problem your boiler is having based on the type of noise it is making. Take a look at our guide to central heating noises to help you determine the cause of your noisy boiler.

Which Boiler Issues Need an Engineer?

Identify the possible cause of a fault with your boiler using the table below, it will also let you know if you’ll need an engineer.

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Problem Possible Cause Do you need an engineer?
No heat or hot water Broken diaphragms and airlocks, failure of motorised valves, issues with the thermostat or low water levels Yes
Leaking and dripping Most common cause is a broken internal component but it will depend where the water is leaking from Yes
Banging, whistling or gurgling noises A common cause is air in the system, alternatively it could be that the water pressure is too low or it’s kettling Yes
Pilot light goes out Could be a broken thermocouple which is stopping the gas supply Yes
Losing pressure There could be a water leak in the system, the pressure relief valve needs replacing or the radiators have been bled recently No unless there’s a leak
Frozen condensate pipe Your boiler should display a fault code or warning notification Yes
Thermostat issues Thermostat may be turned off or not set to the correct settings (time etc.) Consider replacing
Kettling Limescale or sludge building up on the boiler’s heat exchanger Yes
Radiators not getting hot Sludge or air build up in the system or an unequal distribution of heat You will need to bleed the radiators which doesn’t require an engineer unless you don’t feel like carrying out the task yourself.
Boiler keeps switching itself off Could be low water pressure, a problem with the thermostat or a lack of water flow due to a closed valve, air in the system or the pump not circulating the water in the system correctly Yes

Error Codes

Faults with your Glow-worm boilers will be displayed as error codes to help you identify the issue. Familiarise yourself with the error codes using our list of Glow-worm error codes.

Should You Replace Your Glow-worm Boiler Instead?

When you’ve had your Glow-worm boiler for a long period of time, you might be thinking about getting a new one installed. A brand new boiler could be saving you up to £305* a year if you live in a detached home. The table below shows how much you could be saving depending on your current boiler rating and property.

House Type G (<70%) F (70-74%) E (74-78%) D (78-82%)
Semi-Detached £200 £140 £120 £120
Detached £305 £210 £180 £180
Detached Bungalow £155 £105 £90 £90
Mid terrace house £175 £120 £105 £105
Mid terrace house £95 £65 £55 £55

Who Should You Choose to Replace a Glow-worm Boiler?

If you’re looking to replace your Glow-worm boiler then a Gas Safe registered engineer will be needed to carry out the installation. The decision you have to make is whether to go with a local engineer or national company.

With local engineers, you’re likely to be offered a very competitive rate and they’re likely to deliver a personal service throughout your communications.

National companies may cost slightly more but you’ll have the safety of big brand protection and they could provide extra services such as ongoing boiler cover.

We recommend getting up to 3 quotes from different engineers when considering who should carry out any boiler-related work. Using our service you can get free quotes from reliable engineers near you.

Boiler Insurance and Ongoing Cover

If your boiler warranty has ended or will be coming to an end soon, it might be worth considering boiler insurance. This insurance can be taken out with your energy supplier, but there’s absolutely no obligation to do so. When comparing boiler insurance, keep an eye out for ones that offer annual service and safety inspections.

Glow-worm Boiler Warranty

Glow-worm boilers come with 2-7 years of warranty as standard but some models are eligible for up to 15 years of warranty through Glow-worm’s club energy installers. Find out more with our guide to Glow-worm warranties. Keeping the warranty valid means arranging for an annual service of your Glow-worm boiler that will also ensure the safe and efficient running of the unit.

Find trusted engineers near you with our free service by sending us an enquiry today.

*According to the latest figures from the Energy Saving Trust

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