35 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 41-019-14 | Ultracom 2 30sxi | 2010–present |
| 41-019-14 | Ultracom 2 30sxi | 2010–present |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
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Your boiler's electronic display and control panel are failing to communicate correctly, which means you cannot currently adjust or monitor your heating settings.
Your boiler has lost the ability to accurately measure the temperature of the water circulating through your heating system, so it has shut down to prevent damage.
Your boiler has stopped working because a sensor that monitors the temperature of the water returning to the system is reading incorrectly or has disconnected.
Your boiler's temperature sensor is providing faulty readings, so it has safely shut down to prevent overheating.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has stopped working to prevent potential overheating.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal components.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has shut down because the water leaving the boiler is getting much hotter than the water returning, usually pointing to a blockage or a pump issue.
Your boiler is struggling to pump water around your heating system correctly, which is likely due to low system pressure or a blockage.
Your boiler has detected a problem with the internal part that controls the flow of gas, which is preventing it from lighting safely.
Your boiler has stopped working because it cannot confirm that the flame is staying lit safely.
Your boiler is trying to start up, but it cannot get the flame to light, which usually means there is a temporary issue with your gas or ignition.
Your boiler was working but the flame has unexpectedly gone out, causing the system to stop for safety.
Your boiler is struggling to push air through its exhaust system, which prevents it from firing up safely to provide heating or hot water.
Your boiler is struggling to communicate with its internal controls or external thermostat due to an electrical connection issue.
Your boiler has detected an issue with the electrical signal sent to the gas valve, meaning it cannot safely control the gas supply and has stopped working.
Your boiler has detected an issue with the valve that controls the gas supply and has safely shut itself down to prevent any risk.
Your boiler's computer is having trouble reading its internal software, which has caused it to stop working completely to prevent further errors.
Your boiler's internal computer has encountered a serious internal error and can no longer control the system, meaning your heating and hot water will not work.
Your boiler has detected that its internal control electronics are overheating and has shut itself down to prevent damage.
Your boiler is failing to detect the flame correctly, so it has safely shut itself down to prevent any risk.
Your boiler is struggling to keep a steady flame lit, often leading it to cut out for safety.
Your boiler's control panel and its internal computer are not communicating correctly, meaning the boiler has stopped working to prevent errors.
Your boiler is struggling to accurately measure the temperature of the water flowing into your radiators, so it has shut down to prevent overheating.
Your boiler has detected an inconsistent temperature reading between the water leaving the boiler and the water returning to it.
Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from heating your home safely.
Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from safely heating your home.
Your boiler has detected a safety-related issue with its internal heat protection circuit and has shut itself down to prevent potential damage or overheating.
Your boiler has detected an issue with the valve that regulates the gas supply, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has detected that there is not enough water circulating inside the system to carry the heat away, so it has shut down to prevent damage.
Your boiler has detected an unusual and lasting temperature difference between the water leaving it and the water returning to it, so it has safely shut down to prevent damage.
Your boiler is struggling to compare the temperature of the water leaving and returning, meaning it has switched itself off to prevent overheating.
Your boiler has stopped running because it has detected a problem with the safety switch protecting your underfloor heating system.
Your boiler is momentarily checking the temperature of the water circulating back into it to ensure everything is working correctly.
Your boiler is struggling to accurately measure its internal temperature, which is causing it to pause operation as a safety precaution.
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BoilerFaultCodes