The client reported that their gas boiler was providing neither heating nor hot water—a complete loss of function that during winter months represents an urgent situation. Unlike faults that produce error codes or obvious symptoms, this system appeared to be running but not delivering heat where needed.
Complete loss of both heating and hot water typically indicates a problem with either the boiler itself (unable to fire or transfer heat), the controls (not calling for heat correctly), or the distribution system (heat being produced but not reaching its destinations).
The Diagnostic Process
Our heating engineer attended site and conducted a systematic inspection of the boiler and heating system. The investigation covered multiple potential failure points:
Boiler Inspection
The boiler was inspected for visible faults, error codes, and operational anomalies. The gas supply appeared normal, suggesting the boiler was receiving fuel and should theoretically be able to fire.
Radiator Assessment
All radiators throughout the property were checked. The engineer found air trapped in the system and bled each radiator to remove it. Air in radiators prevents proper circulation and can cause symptoms similar to boiler failure—the radiators simply don’t get hot even if the boiler is running.
System Pressure
The sealed system pressure was checked and found to be within acceptable parameters. Low pressure is a common cause of boiler lockout, but this was ruled out.
