Rheem Code 38
Furnace Lockout
What Rheem Code 38 Means
Furnace Lockout – Furnace won't start after repeated ignition attempts
Common Causes
- Safety lockout activated by control board
- Repeated ignition failures
- Faulty ignition sequence
- Flame detection circuit failure
- Control board programming reset
First-Check: Step-by-Step Troubleshooting
- Wait 1 hour for automatic reset
- Check for any error codes repeating
- Verify gas and electrical supply
- Inspect entire ignition system
- Reset control board if equipped
- Call technician for lockout persistence
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