3)Allow the boiler to cool to room temperature and drain the boiler. Remove the
a)Temporarily install a
b)Make sure that this valve is closed and that the water level is at the normal water line.
c)If a king valve is present in the steam main takeoff, close it. Alternatively, temporarily replace enough of the vents on the mains and/or radiators with plugs so that
d)Fire the boiler and allow it to steam until
e)Turn off the burner and immediately fully open the
f)Allow the boiler to blow down until either the water runs clear or the water level reaches the bottom of the gauge glass.
g)Allow all parts of the boiler to cool to room temperature. Drain the boiler completely and remove the
h)If significant mud or scale is still present in the bottom of the boiler, repeat steps (b) through (g) until all mud or scale is removed.
i)Once all mud or scale is removed, replace the
NOTE
A large accumulation of mud or scale in the bottom of the heat exchanger is usually a sign of excessive feedwater
•Make sure that all vents are in working order. Vents should not permit any passage of steam or water.
•Check all steam and return piping for leaks. Be aware that buried return piping can leak and go undetected during normal operation.
4)Clean the boiler flue passages as follows:
a)Remove vent connector and piping.
b)Remove barometric draft regulator.
c)Remove top jacket panel to gain access to boiler flue collector.
d)Unscrew four wing nuts and remove canopy retaining carriage bolts, lift off the canopy and ceramic fiber sealing strips.
e)Unplug the burner, disconnect the oil lines (if the pump is hard piped), and remove the two 5/16” bolts securing the burner door. Open the burner swing door.
f)Thoroughly brush boiler flueways from the top and diagonally between casting pin rows. Be careful when brushing the rear passage not to damage the rear target wall insulation.
g)Vacuum soot and debris from combustion chamber.
h)Check condition of rear target wall insulation, combustion chamber liner, and burner door insulation; replace if required.
i)Check burner head for signs of deterioration. Clean the head of any deposits.
j)Close burner door, reinstall 5/16” bolts, reconnect fuel oil and electrical lines.
k)Installation of boiler canopy, jacket top panel barometric draft regulator and breeching piping is done in reverse order of removal. Make sure canopy is sealed tight to the casting; replace ceramic fiber sealing strips as needed. All vent piping joints must be flue gas leak free and secured with sheet metal screws.