Furnace shows frost protection active / frost alarm, burner may run unexpectedly at low temperature

Safety: Ensure all radiators and pipework are intact; frozen pipes can burst.

• Check actual temperature: Compare room and outdoor temperatures with the values shown on the Hoval display.
• Inspect sensors: If a sensor shows an unrealistically low value, check its location and wiring.
• Adjust settings: In the controller menu, review frost protection setpoints and adjust if necessary according to the manual.
• Thaw frozen sections: If pipes are frozen, thaw slowly using safe methods and repair any leaks before normal operation.