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Boiler Problems & Troubleshooting Guides

Find practical advice for the most common boiler problems, from low pressure and no hot water to leaks, strange noises and fault codes. Follow our step-by-step guides or contact our Gas Safe engineers if you need urgent assistance.
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Meet Common Boiler Problems

Browse our most popular knowledge categories.

Boiler Losing Pressure

Common causes of pressure loss and how to safely repressurise your boiler.
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No Hot Water

Troubleshoot hot water issues and learn what to check before calling an engineer.
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No Heating

Find out why your heating isn't working and the steps you can take first.
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Boiler Leaking

Identify common leaks, possible causes and when professional repairs are needed.
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Boiler Making Noise

Learn what banging, whistling or gurgling noises could mean for your boiler.
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Boiler Won't Ignite

Understand ignition problems and the most common reasons your boiler won't start.
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Boiler Keeps Turning Off

Discover why your boiler keeps shutting down and what may be causing it.
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Radiators Not Heating

Cold radiators? Check the most common causes and simple troubleshooting steps.
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Browse Boiler Brands

Find fault codes, repair advice, servicing tips and installation guides for your boiler brand.
Worcester Bosch logo View Brand →
Ideal Heating logo View Brand →
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Glow-worm boiler logo View Brand →
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Worcester Bosch Fault Codes

EA, E9, E118, E119 and more

Vaillant Fault Codes

F22, F28, F75 and more

Ideal Fault Codes

L2, F1, F4, F9 and more

Baxi Fault Codes

E133, E110, E160 and more

Viessmann Fault Codes

F2, F4, F5 and more

Potterton Fault Codes

E20, E28, E110 and more

Alpha Fault Codes

E10, E20, E34 and more

Quick Checks Before Calling an Engineer

Check Boiler Pressure

Ensure your boiler pressure is between 1 and 1.5 bar when the system is cold.
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Check the Power Supply

Confirm your boiler is switched on and the fused spur hasn't been turned off.
View Fault Codes→

Check the Thermostat

Make sure your thermostat is calling for heat and has working batteries if applicable.
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Check the Condensate Pipe

During freezing weather, a frozen condensate pipe can stop your boiler from working.
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Still having problems? Our Gas Safe engineers are here to help.

Popular Searches

Leaks & Water

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