Mistral Condensing Boiler Error Codes
The Mistral Condensing boiler range is normally extremely reliable and powerful.
Occasionally some things can go wrong, that’s why we’ve created our handy at-a-glance table of Mistral error codes below and a guide to Common Mistral Boiler Problems and Repair Advice.
Should you need professional help with your broken boiler, then simply use our enquiry forms, and we will connect you with the best heating engineers local to you.
Initial user checks
You are able to make some checks before calling out a service engineer.
- Check you have enough fuel: check the sight gauge.
- Check the fuel supply valves are open.
- Check the external fire valve hasn’t tripped: press the trip button.
- Is the boiler electrical supply on?
- Is the control panel high limit thermostat tripped? Check and reset if needed.
- Burner control box locked out: check and press the lens.
Mistral Boiler Error Codes
Listed below are some error codes that could appear on your Mistral boiler.
| Fault | Possible Cause |
|---|---|
| Burner does not start / run | Air locks/ Supply lines blocked or tank vent blocked (no fuel getting into tank) |
| Restriction suspected / fuel supply fault | Power supply to the boiler failed/ Burner control box locked out/ Burner motor fault/ Pump seized |
| Burner fault locks out after 15 seconds | Photocell fault/ Restricted oil supply/ Combustion setting out of specification |
| No flame established (burner fault) | Ignition failure/ Oil restrictor/ Nozzle locked |
| Burner fault runs but continually pulsates | Condensate trap blocked/ flue system blocked/ Baffles wrongly positioned on boiler |
| Lock-out | Losing oil in the supply suction line/ Oil level in tank below minimum level |
| Burner running but smokes | Tank topped with wrong fuel/ Air supply restricted/ Dust build up |
| Burner flame shuts down slowly | Balanced flue system leaking/ Combustion leaks/ Suction line drawing air into fuel |
| Burner fails to reach working temperature | Burner output restricted/ Low efficiency/ Control thermostat fault |
| Oil smells | Oil leakage at connection |
| No hot water | Circulating pump seized/ Programmer channel off |
| Flow and water temperature low | Programmer for CH or DHW are off/ Debris build-up/ Low water supply pressure |
| CH and or DHW not working | Programmer channels are off/ Thermostats fault or turned off |
| Thermostat trips off | Fault circulating pump |
| No CH | Spring fault or return valve not moving or operating properly/ Room stat error |
| No DHW | Spring fault/ Jammed in HW mode/ Flow switch blocked or faulty |
| Discharges on pressure relief valve | Pressure vessel has lost charge/ Insufficient expansion volume |
