20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Promax Ultra
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Your boiler has lost the ability to accurately measure the temperature of the water circulating through your radiators, so it has shut down to prevent overheating.
Your boiler has detected an issue with the ventilation or exhaust system, meaning it has safely shut itself down to prevent any risk of fumes entering your home.
Your boiler has lost the ability to measure the temperature of your hot water, so it has shut down to prevent overheating.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage or potential danger.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is struggling to move water through the system, either because there isn't enough water pressure or because the pump is having trouble circulating it.
Your boiler has detected that the gases it is producing are becoming too hot, so it has safely shut itself down to prevent any damage.
Your boiler has stopped working because it is not receiving enough gas or is failing to stay safely lit.
Your boiler has detected that the internal fan is not spinning or communicating correctly, causing the system to stop heating for safety reasons.
Your boiler is struggling to get water moving through the system as expected before it attempts to fire up.
Your boiler has lost the ability to accurately measure the temperature of the water, so it has safely shut itself down to prevent overheating.
Your boiler has stopped working because it is unable to accurately measure the temperature of the gases leaving the unit, leading the system to shut down for safety.
Your boiler has stopped working because it can no longer accurately read the temperature of the water being heated, so it has shut down as a precaution.
Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low.
Your boiler is struggling to push water through your heating system, which means it has safely shut itself down to prevent overheating.
Your boiler has detected that it is getting too hot or that a sensor measuring the heat of the exhaust gases is giving a faulty reading, so it has automatically shut down for safety.
Your boiler is trying to ignite but cannot detect a flame, likely due to a gas supply issue or a blockage in the combustion process.
Your boiler is struggling to clear exhaust gases properly, so it has safely shut itself down to prevent a potentially hazardous situation.
Your boiler has detected air trapped in the pipes, which is preventing the water from circulating properly to heat your radiators or water.
BoilerFaultCodes