Lennox Error Code 6: Pressure Switch System Lockout
Warning: Your Lennox HVAC system has a pressure switch system lockout, which means it's not running to prevent damage. Call a professional soon.
How to Fix Lennox Code 6
- Step 1: Check and replace your air filter if it's dirty
- Step 2: If the system still won't run, call a professional HVAC technician
How to Reset Lennox Code 6
- 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.
What does 6 mean?
The Lennox 6 error code indicates that the system's pressure switch has detected an abnormal pressure condition, causing the system to shut down. This could be due to a clogged filter, a refrigerant leak, or a faulty pressure switch. It's important to address this issue promptly to prevent further damage to your HVAC system.
Affected Models
- SLP98V
- SLP98
- EL296V
- EL296
- SLP
- SLP
- ELP
- ELP
- NCB
- NPE
- Elite Series
- Elite Series
- Dave Lennox Signature Collection
- Dave Lennox Signature Collection
- ML195
- SLO
- EL296
- SLP98V
- EL296V
- G61
- ELP
- NCB
- NPE
- NPE
- ML195
- ML199
- Elite Series
- Dave Lennox Signature Collection
- Lennox Healthy Climate
- Elite Series
- Elite Series
- Slimline Series
- Slimline Series
- Health Saver Series
- Pace Series
Replacement Parts
| Part | OEM Number | Est. Cost |
|---|---|---|
| Pressure Switch | 42-0227-00 | — |
Related Codes on Same Models
| 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 |
| 5 | Flame Rollout Switch Open | 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 |