Section Iv Service Instructions; Boiler Shutdown And Cool Down Procedures; Cleaning Boiler Heating Surfaces - Burnham 4FHL-63A Installation And Operating Instructions Manual

SECTION IV — SERVICE INSTRUCTIONS
See item 10 under Operating Instruction if it becomes
necessary to add water to the boiler more frequently
than once a month.
Se reporter à l'article 10 dans la section Instructions
de fonctionnement si le remplissage de la chaudière
devient nécessaire plus d'une fois par mois.
1. GENERAL
Inspection should be conducted annually. Service
as frequently as specified in paragraphs below. Before
service or maintenance is performed complete boiler
shutdown/cooldown procedure.
2. BOILER SHUT DOWN AND COOLDOWN
PROCEDURE
NOTE: This procedure is generally required in
preparation for corrective or preventative maintenance
in the unit. This procedure must be supervised by an
individual who is thoroughly qualified in operation and
maintenance of the equipment at hand. This is written
with Steam Boilers in mind, but the principles are
applicable to Hot Water Boilers as well.
A. Decrease plant load as much as possible.
B. Turn boiler switch off. If control power from
burner is used to support accessories, leave
on until boiler system has cooled down.
C. Shut and lock manual gas and oil valves as
applicable.
D. In single boiler installations, some small steam
loads can remain on to assist in a controlled
cooldown of the boiler (i.e., deaerator). In multiple
boiler installations, shut down the non-return
valve and the back up valve. Lock them shut.
E. Allow the boiler feed pump to remain active. As
the boiler cools down, the water level is reduced
by demand or shrinkage. It is best to be aware of
the boiler level at all times.
F. When boiler pressure has decreased to 5 to
10 psi on the pressure gauge, open the boiler
manual vent valve on the top of the boiler. This
is to act as a sentinel against the increase in
pressure and to prevent the boiler from going into
a vacuum. Lock the valve open.
NOTE: Depending on the size of the boiler, the large
mass of heating surfaces that are still hot can cause the
boiler water temperature to increase, even if the gauge
pressure is "0". It is better to allow the entire system to
cool gradually, never force cool the boiler as damage
can also be inflicted due to "thermal shock."
20
G. When boiler and water are below 120°F, shut off
power to the unit and lock out the circuit
breakers.
H. If required, open front and rear doors for
observation of fireside surfaces.
I. Drain boiler down as far as required. (Usually
completely.) Make sure the vent valve on the top
of the boiler remains open. Open and lock the
float control low water cutoff drain valves. These
will serve as additional vents.
J. Shut and lock the boiler feed valves, and any
blowdown valves that can be affected by other
boilers in the same facility (i.e., bottom blow down
valves can tie into a common blowdown
separator in a multiple boiler installation).
K. If necessary to remove handhole and/or manhole
plates for water side inspection or maintenance,
use extreme caution. Loosen the nuts securing
the arch enough to allow the plate to drop
approximately 1/8 inch when tapped loose with
a mallet. Once again, ensure the pressure in the
boiler is "0" before loosening the plate. Remove
the plate the remainder of the way. Wear gloves
and eye protection at all times.
3. CLEAN THE BOILER HEATING SURFACES
AND FLUE
At least once each year, preferably at the end of the
heating season.
A. Clean the Vent System
Vent system should be checked annually for:
1. Obstructions.
2. Accumulations of soot.
3. Deterioration of vent pipe or vent accessories
due to condensation or other reasons.
4. Proper support no sags, particularly in
horizontal runs.
5. Tightness of joints.
Remove all accumulations of soot with a wire
brush and vacuum. Remove all obstructions. Replace
deteriorated parts and support properly. Seal all joints.
B. Clean the Boiler Heating Surfaces
At the end of the heating season, clean boiler
heating surfaces thoroughly. Access to boiler
firetubes may be gained by removing the front
and rear smokeboxes or smokebox doors.
Where applicable, remove the turbulators, paying
close attention to which tubes have turbulators.