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Electrode Boiler
9.3-Monthly maintenance
1.Shut the boiler down and turn off the power supply. Check all electrical connections for tightness.
Be particularly careful during the first few months of service. Check contacts for discoloration,
corrosion, or pitting.
2.Make an instantaneous check of the safety valves. Allow them to slam shut to ensure good seating.
3.Check the elements of the standby heater with a megohmmeter. Test the lead wire to ground. A read-
ing of 25000 ohms or more is satisfactory. Below 25000 ohms indicates a defective element, which
should be replaced at the next scheduled boiler annual inspection.
Standby heater replacement
A.Sketch the wiring hookup of the element head and busses. Identify each wire.
B.Disconnect the wire and remove the element flange bolts. A tapped hole is provided to assist in
breaking the gasket free.
C.Pull the flange and element bundle straight out. Handle the element gently.
D.Remove the faulty element from bundle. Replace with a new element and ferrule.
E.Re-insert element bundle and install with a new gasket and seal. Torque the bolts to 115ft-lb. Re-
wire the elements and busses according to sketch made at beginning
4.The air supply filters (if present) on the feedwater controller and back pressure regulating valve
should be removed and cleaned on a regular basis. Experience will determine the maintenance
interval. It is recommended to periodically remove any condensate in the bowl of the regulator.
5.Check the conductivity cell. Abnormal conductivity readings usually indicate that the cell needs
cleaning or replatinization. If there are any foreign substances on the cell (oil, grease, rust, sediment,
etc.) it must be cleaned. Do not scrape or clean mechanically, as this may remove the coating. The
cell should be dipped into a solution of 10% hydrochloric acid in water and left to soak for five to ten
minutes, as needed. Afterwards, rinse thoroughly in running tap water.
6.Check the entire piping system for leaks.
7.Check the boiler auxiliary equipment.
9.4-Annual maintenance
1.Shut the boiler down, drain the water from the system, and clean out all accumulated scale buildup,
corrosion, and sludge from the pressure vessel.
2.Check for electrode deterioration and erosion of the electrodes, counter electrodes, and stripper of
the regulating shield.
3.Check for erosion of nozzles. Check the nozzle stock for erosion and remove any scale buildup.
4.Check the general mechanical condition of the boiler assembly, paying particular attention to the
reg- ulating shield operating equipment.
5.Check all pressure gauges for accuracy.
6.Remove the circulating pump(s) and inspect for wear of the shaft bearings and pump impeller.
7.Have an approved safety valve service agency check the safety valves for wear and correct settings.
8.Inspect the blowdown valves for seat erosion.
9.Clean the hydraulic pump reservoir, air filter, and suction strainer.
750-272
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