Rheem R801SA furnace code 33: Rollout limit open
Safety issue — act now
What does code 33 mean on a Rheem R801SA (801S downflow) furnace display? Code 33 means a manual-reset limit control, such as a flame-rollout switch, is open. A technician must identify which device opened and why before the furnace runs again.
This condition involves the gas or combustion side. If you smell gas or a CO alarm sounds: leave, then call your gas utility. Diagnostic info here is reference — combustion repairs are for licensed technicians. All six emergency signs →
The manual says not to jumper or reset the rollout yourself. A qualified installer, service agency or the gas supplier must find why it tripped before any reset.
Possible causes
- Insufficient combustion air reaching the burners TECH
- Blocked flue or restricted heat exchanger passages TECH
- Damaged heat exchanger affecting flame and flue flow TECH
Parts for this code
No model-verified part number is listed here. Have the fault diagnosed and the correct part matched to your furnace before ordering.
Questions about this code
What does code 33 mean on a Rheem R801SA (801S downflow) furnace display?
Code 33 means a manual-reset limit control, such as a flame-rollout switch, is open. A technician must identify which device opened and why before the furnace runs again.
How do I fix Rheem R801SA furnace code 33?
If you smell gas or a CO alarm sounds, leave now without touching switches or the thermostat, and call the gas utility or 911 from outside. Otherwise set the thermostat to OFF, keep the furnace off and do not reset the rollout. Book service.
How much does it cost to fix Rheem R801SA furnace code 33?
Diagnosis centers on combustion air, venting and heat-exchanger condition. Cost depends on what the technician finds; resetting the switch alone is not a repair.
Applies to
R801SA / 801S downflow single-stage 80% furnace with PSC motor
Different Rheem generations use different code maps. If your series isn't listed, don't assume this meaning — check your blower-door label.
Verified against Installation Instructions for Downflow Single Stage Gas Furnaces, p.34
Verified against Rheem 801S Series Installation Instructions — OEM143-14 mirror, p.34
Verified against Rheem 801S Series Installation Instructions — OEM143-14 mirror, p.43
Last verified 2026-10-07 · page updated 2026-10-07 · how we verify
Related Rheem furnace codes
These codes use the same rheem 801s downflow single-stage control (manual 92-24161-143-14) system.