Immergas Victrix fault 45

What it means

The boiler detects a sudden, unexpected increase in the ΔT between the flow probe and the system return probe.

Likely causes

1. Insufficient water circulation in the boiler
2. Pump not configured according to system requirements
3. Faulty return probe
4. No/insufficient water circulation in the boiler
5. Return probe malfunction
6. Lack of water in the appliance
7. Little water circulation in the system
8. Blocked pump
9. Disconnected PWM signal wire (when boiler is requesting ignition but pump stays in stand-by)
10. Disconnection of the PWM control signal between PCB and pump
11. Boiler electronics not requesting pump ignition (normal, condition OK)
12. Boiler electronics requesting pump ignition but pump not responding (faulty condition, probable disconnection of the PWM signal)
13. Blocked pump (Par. 1.29)
14. Drain trap not yet filled with condensate on first start-up, allowing combustion products to escape via condensate drain
15. Long period of inactivity causing pump/rotor seizure

Where to start

1. Make sure there is water circulating in the boiler
2. Check that the pump is configured according to system requirements
3. Check that the return probe works properly