BoilerFaultCodesVokera 73 Fault Code
The Vokera 73 fault code means: your boiler has detected an unusual temperature reading or a possible blockage that is preventing water from circulating correctly.. It appears on 3 Vokera models in our database.
Technical description: Temperature anomaly
What causes the Vokera 73 fault?
This fault occurs when the boiler detects a rapid rise in temperature because water isn't moving through the system quickly enough. The most common reasons are a failing circulation pump that can't push the water round, or a sensor that has become faulty and is giving the boiler an incorrect reading.
This issue often surfaces in autumn when the heating is turned back on for the first time, as internal pump components can seize up after being idle during the summer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Vokera models that show the 73 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera 73 fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026