Boiler Error Codes: What They Mean and What to Do
Boiler error codes tell you something specific has gone wrong. Some you can fix yourself, others need an engineer. Here are the most common ones explained.
What are boiler error codes?
When something goes wrong, your boiler displays a code on its screen to tell you what the problem is. These are sometimes called fault codes or lock-out codes. The boiler will usually stop working until the issue is resolved.
Low pressure codes
Codes like E119 (Baxi), F1 (Ideal), or F22 (Vaillant) mean the water pressure has dropped too low. Check the pressure gauge - if it is below 1 bar, repressurise the system using the filling loop. If the pressure keeps dropping, call us to find the leak.
Ignition failure codes
Codes like E133 (Baxi), F1/L1 (Ideal), or F28 (Vaillant) mean the boiler tried to fire up but could not. Check that your gas supply is on - if other gas appliances work, the issue is with the boiler and you need an engineer. Do not try to fix ignition problems yourself.
Overheating codes
Codes like E125 (Baxi), L5 (Ideal), or F27 (Vaillant) mean the boiler is getting too hot. This can be caused by a circulation pump failure, a blockage in the system, or a faulty thermostat. Turn the boiler off and call an engineer - do not keep resetting it as overheating can cause serious damage. A power flush may be needed if the cause is a system blockage.
When to reset and when to call us
If you get a one-off error after a power cut or a brief gas supply interruption, try resetting the boiler once using the reset button. If the code comes back, or if the error relates to ignition, overheating, or a gas valve fault, call us on 01932 943 009. Repeatedly resetting a boiler without fixing the underlying fault can make the problem worse.
Need help with this?
Call us on 01932 943 009 or email info@hphsolutions.co.uk. We cover Surrey, Hampshire, Berkshire and London. Free quotes, no obligation.
