What the symptom means

The burner starts, a flame appears for a short time, and then the control unit stops operation. This often indicates that the flame is not confirmed correctly.

What to check

  • If the flame forms steadily.
  • If the flame sensor is clean and correctly positioned.
  • If the wiring and grounding are correct.
  • If the control unit receives a proper monitoring signal.

Oil and gas

The logic is the same: the unit must "see" a reliable flame within the allotted time. The exact method of measurement varies by burner.

Example

If the flame is clearly visible but the burner goes into lockout a few seconds later, the check shifts to flame monitoring rather than just fuel supply.

Safety

Combustion and fuel checks should be performed by a qualified technician. Do not bypass flame sensors or safety units.