Fall is approaching, and it's time to prepare boilers for start-up after the
summer! The following lists (although not all-inclusive) can serve as a guide
for those responsible for start-up operations.
Remember: The entire system must be carefully checked and operating
procedures reviewed before the boiler is placed in operation. Boiler operators
and other responsible personnel, such as supervisors, must be up to date on
current codes and procedures.
All manufacturers of boilers and
fuel-burning systems supply operating manuals with their equipment.
Unfortunately, many boiler rooms do not have manuals and operating instructions
available. Most of these documents have either been lost or misplaced. It is the
responsibility of the supervisor to obtain these publications and see that they
are read, understood, followed, and available in the boiler room.
Maintenance During Summer Lay-Up
The summer shutdown
period is a good time to accomplish necessary boiler and fuel-burning system
preventive maintenance. A suggested checklist of such maintenance follows:
- Drain and flush the boiler, open all handholes and manholes, clean and
remove soot and scale from the firesides. Examine the boiler for damage and
- Have the boiler inspected by an authorized inspector, as required.
- Install new gaskets, replace all handhole and manhole covers, refill boiler,
and perform a hydrostatic test, if required.
- Institute a suitable boiler water treatment program to reduce scale buildup
- Have the fuel-burning equipment cleaned and adjusted by a competent service
technician. Verify operation of all operating and limit controls, interlocks,
and gages. Have the technician disassemble the low-water cutoff and
water-feeding devices, then clean, recondition, and reassemble them. Have the
technician leak test all fuel safety shutoff valves.
- Lubricate all mechanical equipment such as fans and pumps. Verify motor
- Check all boiler piping for leaks and missing insulation.
- Make sure provisions are made for establishing and keeping a boiler log.
Immediately prior to boiler start-up:
- Check that all ventilation and combustion air openings and louvers are clean
and free of debris.
- Verify boiler water level.
- Make certain all stack dampers are open.
- Examine the boiler furnace for foreign material.
- Check furnace and flue passes for fuel accumulation.
- Make sure manual fuel valves are open.
After completing start-up checks, close
the operating switch and commence the normal starting sequence. The following
list suggests a typical starting sequence:
- Ensure operating controls are closed.
- Ensure interlocks (safety controls) are closed.
- Start fans and purge the boiler.
- Ensure purge requirements are met.
- Energize igniter.
- Prove ignition flame within 10 seconds.
- Energize main fuel valve(s).
- Establish and monitor main flame.
- De-energize ignition, main flame proven.
- Release firing rate (combustion) control to demand.
- Ensure normal operation.
This starting sequence should be carefully observed to make sure all steps
are normal. Readings on flame signal strength meters (if fitted) should be
observed and recorded in the boiler log.
Normal shutdown should be initiated by opening the manual burner switch.
After the post-purge has been completed, check the furnace for flame cutoff and
make sure there is no residual flame. Have fuel safety shutoff valves repaired
or replaced if required.