Safety: Frequent cycling can reduce boiler life but is not usually an immediate hazard.

Adjust setpoints: Lower the flow temperature on the Herz boiler to lengthen run times.
Check thermostat location: Ensure the room thermostat is not near heat sources or in direct sunlight.
Enable modulation: If available, enable weather compensation or load compensation features in the Herz controller.
Hydraulic changes: A heating engineer may need to add a buffer tank or bypass to increase system volume.

Boiler cycles on and off rapidly without reaching room temperature

Possible Causes