A5
Miller Flame Rollout or Manual Reset Limit Open

Miller furnace digital display shows A5; blower may run continuously.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Flame rollout due to blocked heat exchanger, Blocked flue, Cracked heat exchanger, Tripped manual-reset rollout switch

How to Fix / Troubleshooting

Critical safety: Do not repeatedly reset rollout switches. Flame rollout can indicate a dangerous condition and carbon monoxide risk.

  • Visual inspection: Look for soot, scorch marks, or melted wiring around the burner area. If present, shut the furnace down and call a professional.
  • Check flue and intake: Ensure the vent system is intact and unobstructed. Repair any disconnected or corroded sections.
  • Reset rollout (if safe): After confirming there is no obvious blockage, press the reset button on the rollout switch. If it trips again, discontinue use and have the furnace inspected.
  • Professional heat exchanger inspection: A licensed technician should inspect for cracks or blockages and recommend heat exchanger or furnace replacement if needed.
Advertisements

Repair Difficulty

Professional Required 5/5

Required Part

Flame Rollout Switch
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements