Verified boiler fault code
Grant burner lock-out Fault Code (Vortex Pro External)
The Grant Vortex Pro External control panel provides a burner lock-out reset button; this is an oil-burner indication rather than a numeric boiler code.
Safety disclaimer
Fault code summary
- Manufacturer
- Grant
- Fault code
- burner lock-out
- Fault type
- Safety lockout, Flame failure
- Severity
- high
- Reset
- The manual identifies a lock-out reset button, but repeated resetting of an unresolved burner lock-out is not safe; use a qualified oil-heating engineer.
- Applicable models
- Vortex Pro External 15-26, Vortex Pro External 26-46, Vortex Pro External 46-70
Quick answer
The Grant Vortex Pro External control panel provides a burner lock-out reset button; this is an oil-burner indication rather than a numeric boiler code.
What does this fault code mean?
The Grant Vortex Pro External control panel provides a burner lock-out reset button; this is an oil-burner indication rather than a numeric boiler code.
Common causes
This information was not provided in the verified manufacturer source.
Symptoms
- Burner lock-out indication
- Burner does not fire
What can the homeowner safely check?
- Check that the boiler's normal power switch is on and record the indicator; do not open the burner or alter oil settings.
Boiler reset information
The manual identifies a lock-out reset button, but repeated resetting of an unresolved burner lock-out is not safe; use a qualified oil-heating engineer.
When should I call an engineer?
Contact a suitably qualified heating engineer when the fault persists, the boiler locks out, or the manufacturer instructions do not resolve it. For gas appliance work in the UK, use a Gas Safe registered engineer.
Engineer diagnosis
- A qualified oil-heating engineer should investigate the burner, oil supply, ignition and combustion safety.
Applicable boiler models
Related fault codes
- overheat thermostat trip — Vortex Pro External
The safety overheat thermostat automatically switches the boiler off if the heat exchanger exceeds 110°C ± 3°C.
Read fault code - pump Run/Fault LED: red — Vortex Pro External
The Wilo-PARA circulating-pump table identifies a constant red Run/Fault LED as the pump being stopped.
Read fault code
Manufacturer documentation
Grant Vortex Pro External Condensing Oil Boiler Range Installation and Servicing Instructions, UK DOC 0121 Rev 2.1Figure 1-1: Vortex Pro External boiler control panel and reset button; the controls include a 'Lock-out' reset button.
Last verified
2026-09-12
Frequently asked questions
What does Grant burner lock-out mean?
The Grant Vortex Pro External control panel provides a burner lock-out reset button; this is an oil-burner indication rather than a numeric boiler code.
Can I reset a Grant burner lock-out fault?
The manual identifies a lock-out reset button, but repeated resetting of an unresolved burner lock-out is not safe; use a qualified oil-heating engineer.