Lennox Error Code 5: Flame Rollout Switch Open
Warning: Your Lennox heating system has detected a potential safety issue and has shut down. Do not attempt to operate until the problem is resolved.
LED Blink Pattern
LED blinks 5 times.
How to Fix Lennox Code 5
- Check if the gas valve is closed. If it is, turn it to the 'pilot' position and try to restart your system.
- Inspect the area around your furnace for any obstructions or debris that could be causing the switch to remain open.
- Contact a professional HVAC technician if the problem persists.
How to Reset Lennox Code 5
- Turn off the furnace power switch, usually located on or near the unit.
- Turn off the circuit breaker for the furnace. Wait 30 seconds.
- Restore power at the breaker and flip the furnace switch back on.
- Set the thermostat to call for heat. If the error code returns after 2-3 ignition attempts, the fault requires repair.
Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.
What Does Lennox Error Code 5 Mean?
The Flame Rollout Switch Open error code (5) on your Lennox heating system indicates that the switch designed to prevent flame rollout is open, causing the system to shut down. This could be due to a faulty switch, improper gas pressure, or a problem with the ignition system. It's important to address this issue promptly to prevent potential safety hazards and damage to your system.
Common Causes
- Faulty flame rollout switch
- Improper gas pressure
- Problem with the ignition system
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| System shows error code 5 | Inspect the flame rollout switch for any signs of damage or wear | Switch should be closed and in good working condition |
| Switch appears functional | Measure gas pressure at the furnace inlet using a manifold gauge set | Gas pressure should be within the manufacturer's specified range (usually 7-11 inches W.C.) |
Applicable Lennox Models
- Lennox Healthy Climate(dual_fuel)
- Dave Lennox Signature Collection(gas)
- EL296(electric)
- EL296V(electric)
- ELP(electric)
- Elite Series(electric)
- G61(gas)
- Health Saver Series(electric)
- ML195(dual_fuel)
- ML199(gas)
- NCB(electric)
- NPE(electric)
- Pace Series(electric)
- SLO(gas)
- SLP(electric)
- SLP98(gas)
- SLP98V(gas)
- Slimline Series(electric)
Replacement Parts
| Part | OEM Number | Est. Cost | Where to Buy |
|---|---|---|---|
| Flame Rollout Switch | 30-100-0000 | — | Find Part |
Related Codes on Same Models
Other codes that affect the same Lennox model families as 5.
| Code | Description | Severity |
|---|---|---|
| 1 | Ignition Failure | Warning |
| 2 | Pressure Switch Stuck Closed | Warning |
| 3 | Pressure Switch Stuck Open | Warning |
| 4 | High Limit Switch Open | Warning |
| 6 | Pressure Switch System Lockout | Warning |
| 7 | Ignition Lockout | Warning |
| 8 | Control Board Error | Warning |
| 9 | Line Voltage Polarity Incorrect | Warning |
| E250 | Lennox Code E250 - Indoor Blower Communication Error | Warning |