7 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 |
|---|---|---|
| 41-592-34 | Promax SL 12 Heat ErP | 2006–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 has detected that it is not getting enough water or the water is not flowing through it properly, which usually happens if the system needs topping up.
Your boiler is having trouble detecting the temperature of the water used for your taps, which means it may struggle to provide consistent hot water.
Your boiler has stopped working because the internal fan, which safely exhausts gases, is unable to start or spin at the correct speed.
Your boiler has stopped working because it failed to light the flame, which usually means it is not getting gas or there is a temporary safety blockage.
Your boiler has automatically shut down because it has detected that it is getting dangerously hotter than it should be.
Your boiler's main electronic control board has failed, which means the system cannot safely operate and has shut down.
Your boiler has detected a faulty temperature sensor which means it can no longer accurately monitor how hot the water is getting.
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BoilerFaultCodes