All mechanical devices occasionally malfunction or operate below a commonly accepted level of efficiency. Coal stokers are no exception to this rule. Table 3-1 lists the conditions that indicate faulty operation:
Table 3-1 Troubleshooting Coal Stokers
| Symptom and Possible Cause | Possible Remedy |
| Abnormal noises. | |
| (a) Loose pulleys or belt. | (a) Tighten or replace. |
| (b) Dry motor bearings. | (b) Oil the bearings. |
| (c) Worn gears. | (c) Oil or replace. |
| (d) Gears lack oil. | (d) Oil the gears. |
| Motor will not start. | |
| (a) Hard clinkers over or on retort. | (a) Remove the clinkers. |
| (b) Foreign matter caught in the feed screw. | (b) Remove the foreign matter. |
| (c) Packing of coal in the retort caused by the end of the feed screw being worn. | (c) Remove packed coal from the retort and replace feed screw. |
| Stoker operates continuously. | |
| (a) Controls out of adjustment. | (a) Contact manufacturer for a service call. |
| (b) Dirty fire. | (b) Rebuild or clean fire. |
| (c) Fire out. | (c) Rebuild fire. |
| (d) Dirty furnace or boiler. | (d) Clean furnace or boiler. |
| Furnace filled with unburned coal. | |
| (a) Clinkers clogging the retort. | (a) Remove the clinkers. |
| (b) Coal feed set too high. | (b) Reduce coal feed setting. |
| (c) Insufficient air getting to the fire. | (c) Open manual damper. If this does not help, check air ports for clogging. Also, check the windbox. If it is full of siftings, they should be removed. |
| (d) Windbox filled with siftings. | (d) Empty windbox. |
| Stoker will not run. | |
| (a) Limit control has shut off furnace or boiler due to overheating. | (a) Allow limit control time to cool off. |
| (b) Low-water cutoff has shut down the boiler. | (b) Check water level in boiler and correct. |
| (b) Low-water cutoff has shut down the boiler. | (b) Check water level in boiler and correct. |
| (c) Gear case has been exposed to water. | (c) Do not try to operate the stoker. Drain and flush out the gear case immediately and refill with oil. |
| (d) Blown fuse. | (d) Replace fuse. |
| (e) Tripped circuit breaker. | (e) Reset circuit breaker. |
| Smoke backed into hopper. | |
| (a) Hopper empty or low in coal | (a) Fill the hopper to the proper level. |
| (b) Clinker obstructing the retort. | (b) Remove clinker. |
| (c) Clogged smoke back connection. | (c) Remove obstruction. |
| (d) Fire burning down in the retort. | (d) Check air supply (fire may be getting too much) or rate of coal feed (may be too low). |
| Fire is out. | |
| (a) Empty hopper. | (a) Refill to proper level. |
| (b) Clinkers obstructing the retort. | (b) Remove clinkers. |
| (c) Switch may be off. | (c) Place in on position. |
| (d) Blown fuse. | (d) Replace fuse. |
| (e) Tripped circuit breaker. | (e) Reset circuit breaker. |
| (f) Failure in electric controls. | (f) Contact manufacturer for a service call. |
