| Odor, soot and smoky fire | 1. Insufficient combustion air |
| 2. Lack of proper draft |
| 3. Cracked/plugged heat exchanger |
| 4. Burner not adjusted properly with combustion kit |
| 5. Improper setting of barometric draft control |
| 6. Oil leaks |
| 7. Wrong nozzle size, or nozzle worn or partially clogged |
| 8. Improper setting of electrodes |
| 9. Plugged oil filter |
| 10. Fuel pump cutoff valve not cutting off |
| 11. Nozzle or electrodes improperly positioned |
| 12. Leakage on return side of air distribution system |
| 13. After drip, reflected heat, or impingement of flame |
| 14. Improper or distorted end cone |
| 15. Air leakage into oil pump supply line |
| 16. Burner blower air inlet restricted or burner blower wheel dirty |
| 17. Restricted flue |
| Delayed ignition | 1. Cracked, dirty or loose electrodes |
| 2. Electrodes not properly adjusted |
| 3. Incorrect nozzle |
| 4. Improper primary air adjustment |
| 5. Faulty ignition transformer |
| 6. Water in fuel oil |
| 7. Incorrect pump pressure |
| 8. Furnace not properly set-up |
| 9. Air leakage into oil supply line |
| Burner will not operate | 1. Open switch |
| 2. Open fuse or circuit breaker |
| 3. Burner motor overload open |
| 4. Thermostat improperly set |
| 5. Burner primary control safety open |
| Burner motor runs but does not (ire | 1. Oil supply insufficient |
| 2. Faulty oil pump |
| 3. Broken oil pump drive coupling |
| 4. Coke deposits on electrodes |
| 5. Air in oil supply line |
| 6. Restricted oil supply line |
| 7. Clogged nozzle |
| 8. Restricted oil line filter |
| 9. Leak in oil line |
| 10. Failed ignition transformer |
| 11. Electrodes not properly set |
| 12. Dirty fire detector |
| Pulsations | 1. Improper nozzle |
| 2. Inadequate draft |
| 3. Air in oil line |
| 4. Clogged flue |
| 5. Furnace not properly set-up |
| 6. Partially clogged pump strainer or oil line filter |
| 7. Nozzle plugged |
| 8. Nozzle too far forward in air tube |
| 9. Barometric damper set wide open |
| Cad cell not functioning | 1. Requires direct view of flame |
| 2. External light effecting cell operation |
| 3. Remove cad cell and check with an ohmmeter: |
| a. With cad cell covered, the resistance should be over 100K ohms |
| b. With cad cell exposed to room light, the resistance should be under 1.5 K ohms |
| Low CO.’ | 1. High draft through furnace |
| 2. Improper primary air adjustment |
| 3. Damaged combustion chamber |
| 4. Faulty nozzle |
| 5. Incorrect oil pressure |
| 6. Draft regulator improperly set |
| 7. Incorrect fuel/air mixture |
| High stack temperatures | 1. Damaged combustion chamber |
| 2. Furnace not set-up with combustion kit |
| 3. Undersized return air |
| 4. Overfired furnace |
| 5. Dirty heat exchanger |
| 6. High draft, barometric damper not properly set |
| 7. Excessive temperature rise |
| 8. Air shutter adjustment open too much. |
| High smoke reading | 1. Lack of combustion air |
| 2. Inadequate overfire draft |
| 3. Incorrect oil pressure |
| 4. Dirty burner blower wheel |
| 5. Incorrect nozzle |
| 6. Faulty oil pump |
| Burner motor runs but does not fire | 7. Dirty oil |
| 8. Burner motor not obtaining full speed |
| 9. Damaged combustion chamber |
| 10. Flame impingement |
| 11. Incorrect fuel/air mixture |
| Poor draft – overfire and stack | 1. Improperly sized chimney or not enough chimney height |
| 2. Holes or cracks in chimney |
| 3. Restricted chimney |
| 4. Too many 90 degree elbows in vent pipe |
| 5. Outside chimney too cool |
| 6. Cool flue gases |
| 7. Barometric damper not properly set, sticking or in wrong location |
| 8. Oil furnace and fireplace chimney interconnected |
| 9. Heat exchanger passages plugged |
| 10. Overfired furnace |
| 11. Improper air shutter adjustment |
| Noisy Operation | 1. Bad coupling alignment |
| 2. Air in oil supply line (use only good flare fittings) |
| 3. Tank hum on two-pipe system and inside tank |