Troubleshooting Coal Stokers

{0 Comments}

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.

Leave a Comment

Your email address will not be published.