replace cable.
8)Reinstall burners, being careful to put the pilot main burner in its original location.
9)Inspect all boiler wiring for loose connections or deterioration.
10)Inspect the vent system:
•Make sure that the vent system is free of obstructions.
•Make sure that all vent system supports are intact.
•Inspect joints for signs of condensate or flue gas leakage.
•Inspect venting components for corrosion or other deterioration. Replace any defective vent components.
11)Inspect the boiler and system for leaks.
12)Inspect the low water
•For Hydrolevel CG400A low water
•For McDonnell & Miller #67 low water
13)Allow the boiler to cool to room temperature. Remove the drain valve and 2 x 3/4 bushing on the left side of the boiler. Use a flashlight to inspect the bottom row of pushnipples for accumulated scale or mud. If a significant amount is present, use the following procedure to clean the inside of the heat exchanger:
a)Temporarily install a 1 1/4 inch or larger full port ball valve in place of the boiler drain. Temporarily pipe the outlet of this valve to a location where hot water and steam can be safely discharged.
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 burners 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
14)Place the boiler back in operation using the procedure outlined in
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.
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