Evoqua Wallace&Tiernan 50-200 Series, Manual

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WT.050.200.001.UA.IM.0814
50-200 EVAPORATOR FOR CHLORINE
38
EVOQUA W3T98237
An annual inspection of the cathodic protection anodes will, under normal
conditions, show that the anodes are almost expended. Replace the four mag-
nesium anodes. After the first replacement, they should be replaced annually.
Before new anodes are installed, it is recommended that the water be drained
from the system and an inspection of the tank and cylinder be made. Sludge
formed by the corrosion of the anodes should be flushed from the hot water
tank and discharged through the water overflow line.
If the cathodic protection system has been operated in the recommended
range, little or no corrosion will be found. Add fresh water after the new an-
odes have been installed. The cathodic current can be increased by adding
1/4 pound of sodium sulfate, U23934, or decreased by adjusting the poten-
tiometer on the evaporator control panel. If a current above 250 milliamps
is maintained the anodes will deteriorate quickly and the anode debris will
be too large to be washed out of the water tank drain.
4.7.1 Anode Removal
The anodes can be replaced during the annual inspection. The Evaporator
should be shut down by following section 4.12, “In Place" Cleaning of the
Evaporator Cylinder, to and including step a(3). Continue by performing the
following: Refer to dwg. 50.200.060.010.
a. Grasp the anode knob (111) and lift the anode (114) above the top of the
water tank.
b. When the anode (114) is exposed hold it with pliers so it can not spin and
unscrew the knob (111).
c. Lift off the wire lugs and washer (112).
d. Withdraw the old anode (114) completely and discard.
e. Repeat this process for the other three anodes (114).
4.7.2 Anode Installation (Refer to dwg. 50.200.060.010)
a. Place a new anode (114) into the grommet (110) on the top of the water
tank, taking care not to let the anode drop below the top of the water tank.
b. Put the washer (112) and the wire lugs onto the knobs (111) threaded
post and screw the knob (111) into the anode (114).
c. Grasp knob (111) and lower anode so it is supported by the grommet (110).
d. Repeat step c for the other three anodes.