Why Proper Fault Finding Is Important
Many boiler problems are misdiagnosed, leading to unnecessary parts being replaced or repeat visits.
Accurate fault finding identifies the real cause of the problem before any repair work is carried out.
This approach saves time, avoids wasted costs and ensures the correct repair is carried out.
Common Boiler Problems We Diagnose
• No heating or hot water
• Boiler not firing
• Low or fluctuating pressure
• Boiler making unusual noises
• Intermittent heating faults
• Error codes and lockouts
• Pumps not circulating
• Wiring and control faults
• Leaking boiler
• heating on, when hot-water on
• Smells of gas from boiler
• hot water temp to low
• heating not hot enough
• Vaillant storage tank faults
• No display on boiler
• Persistent F75 issues.
• F81 - F91
• F00 - F01
• F27 - F62 - F61
• F56 - F57
• F83 - F84 - F71 - F72
• F75 - F22 -F25
• F28 - F54 - F29
Recent Fault Diagnosis Examples
Real recent diagnostic work carried out on customer systems.
• PCB fault identified during diagnostic testing
• circulation fault traced to pump failure
• wiring fault located and corrected
• sensor fault causing intermittent shutdown​
• Flue leaking causing F54
• Pump seized - F75 = cleaned system + filter
• Boiler shower F25 = blocked canoe filter
• Replacement gas valve = blocked condense
