On some Keeprite models, code 33 may indicate flame rollout switch open; burners shut off quickly after ignition.
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.
Possible Causes
How to Fix / Troubleshooting
Critical safety warning: Flame rollout indicates combustion products leaving the burner area. Turn off gas and power immediately. Do not attempt to repeatedly reset rollout switches.
Steps (visual only):
- Inspect rollout switches: Locate rollout switches near the burners. If manual reset type, note if tripped but do not reset until cause is found.
- Check for visible blockage: Look for debris, rust, or collapsed metal in the burner area or flue connection.
- Do not operate furnace: Leave the furnace off until a licensed technician inspects the heat exchanger, venting, and gas input.
This condition requires professional diagnosis. A cracked heat exchanger or blocked flue is a serious carbon monoxide hazard.
Repair Difficulty
Required Part
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