Fix & Repair Engineers were called out to a busy commercial kitchen in Kensington after staff reported issues with a gas hob not staying alight and visible flame impingement on the burners. What initially appeared to be a simple ignition problem turned out to be a combination of a failing thermocouple and blocked injectors affecting flame quality and safety.
Our commercial catering gas engineer attended promptly to diagnose the cause and restore a safe, stable flame pattern across the hob.
The Call – Kensington, London
The client requested a commercial catering gas engineer to attend their Kensington kitchen, reporting:
- A hob burner that would not stay alight
- Flame impingement on the left and right burners
- Concerns that the flame picture did not look normal or safe
With gas appliances, any abnormal flame behaviour can indicate an underlying safety or combustion issue. We prioritised the visit to minimise disruption to service and address any potential risks.
Initial Inspection & Safety Checks
On arrival, our Gas Safe registered engineer:
- Carried out visual checks on the hob, burners and oven section below
- Confirmed the reported fault with one burner failing to hold the flame
- Observed flame impingement and poor flame shape on adjacent burners
- Isolated the appliance and performed the necessary gas safety checks before dismantling
Once the appliance was made safe, a more detailed investigation of the burner components and safety devices was carried out.
Stripping Down the Hob & Oven
To properly assess the condition of the safety controls and burner assembly, the engineer:
- Removed the hob tops to gain access to the burners, injectors and thermocouples
- Checked the burner caps and ports for signs of contamination, debris or distortion
- Inspected the thermocouples and their seating positions in relation to the burner flames
- Opened the oven section to ensure there were no associated issues affecting combustion or flame stability
This strip-down confirmed there were issues both with one of the thermocouples and with the cleanliness of the injectors and burners.
Diagnosis – Failing Thermocouple & Blocked Injectors
Following testing and inspection, the engineer identified two main faults:
- One burner thermocouple was failing – it was not consistently proving the flame, meaning the gas valve would shut off and the burner would not stay alight.
- Blocked or partially restricted injectors and burner ports – contamination and build-up were affecting gas flow and air mix, causing flame impingement and an incorrect flame picture.
The video captured on site clearly shows the difference between:
- The incorrect flame pattern, with flame impingement and poor definition on the left and right burners
- The correct flame picture, with stable inner and outer cones after servicing
These issues, if left unresolved, could lead to poor combustion, inefficient operation and potential safety concerns.
Work Completed
To restore safe and reliable operation, our engineer carried out the following work:
Serviced the failing burner thermocouple:
- Cleaned and correctly re-seated the thermocouple in the flame path
- Tested its operation to confirm it was now correctly holding the flame and keeping the gas valve open when the burner was lit
Serviced and cleared the injectors and burners:
- Removed the burners and injectors for cleaning
- Cleared any blockages and debris affecting gas flow
- Reassembled the burner parts, ensuring correct alignment and fit
Checked the flame pattern across all burners:
- Confirmed a stable, well-defined flame with proper inner and outer cones
- Verified there was no longer any flame impingement on the burner surfaces
All work was completed in line with Gas Safe requirements, with the appliance thoroughly tested before being returned to service.
Outcome & Next Steps for the Client
Following the repair and service:
- The previously faulty burner now stays safely alight, with the thermocouple correctly sensing and holding the flame.
- The flame impingement issue has been resolved, with all burners showing a correct flame picture with balanced inner and outer cones.
- The appliance operates more efficiently and safely, reducing the risk of incomplete combustion or further nuisance faults.
Our engineer also advised the client on the benefits of regular servicing for gas hobs and ranges, especially in busy commercial kitchens where grease, food particles and general contamination can quickly affect burner performance.
Need an Emergency Gas Catering Engineer?
If your commercial gas hob, range or oven is not staying alight, showing signs of flame impingement, or the flame just “doesn’t look right”, it’s essential to have it checked by a Gas Safe registered engineer.
Fix & Repair Engineers provide:
- Rapid response across London and the Home Counties
- Expert diagnosis of burner, injector and thermocouple faults
- Safe, compliant repairs to keep your kitchen running smoothly
If you’re experiencing issues with your commercial gas hob or any other catering equipment, get in touch with Fix & Repair Engineers for a fast, professional gas catering call-out.
With many years on the tools in all aspects of the engineering industry has given me a second to none skill set which enables me to provide a leading professional service to my customers with a wealth of knowledge and highly skilled engineers to successfully cover all your plumbing, heating, AC and catering equipment requirements.
