Evoqua Wallace&Tiernan 50-200 Series, Manual

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WT.050.200.001.UA.IM.0814
50-200 EVAPORATOR FOR CHLORINE
36
EVOQUA W3T98237
c. Remove the pressure switch-diaphragm capsule assembly from the pressure
relief system at the point where the diaphragm capsule bottom connec-
tion and the expansion tank reducing bushing meet. Do not remove the
reducing bushing from the expansion tank, as this is a permanent joint.
d. Using the Resistance Mode, connect a volt/ohmmeter across the “C” (Com-
mon) and “NO” (Normally Open) terminals.
e. Connect the pressure switch-diaphragm capsule assembly to a controlled
pressure source. Install a calibrated pressure gauge in the line to the source.
f. Raise and lower the pressure to determine if the switch is functioning
properly and at what pressure the switch closes.
g. The pressure switch should be able to close repeatedly on a rising pressure
at 15 to 20 psi. If it does not, adjust the response point by turning counter-
clockwise the knurled nut on the switch located below the microswitch.
Repeat step f and this step to confirm proper actuating pressure.
h. Reconnect the alarm wiring and the conduit to the switch and replace the
front cover.
i. Energize the alarm portion of the electrical circuit.
4.5 Automatic Water Level Control and Low Level Switches
Water level is sensed by four stainless steel probes (one common, one low
level, and two differential service) mounted in the probe housing block on the
top of the tank. Two independent switches are actuated by these probes. The
differential service probes actuate the Automatic Water Level Control Switch
filling the evaporator hot water tank 2/3 to 3/4 of the height of the sightglass
and will refill the tank when the water level has dropped to about two inches or
more below this position. The Low Water Level switch will operate just before
the water level drops below the sightglass. The probe lengths are pre-cut and
no adjusting is required.
Periodically clean the sightglass tube in the water level indicator on the front
panel so that the water level can be easily seen. The tube is easily accessible
after removing the plastic indicator cover.
WARNING: TO AVOID SEVERE PERSONAL INJURY FROM BURNS DUE TO
THE HOT WATER IN THE SIGHTGLASS TUBE, TURN THE POWER OFF AND
DRAIN THE TANK ENOUGH SO THAT NO WATER IS VISIBLE IN THE SIGHT-
GLASS. ALLOW THE SIGHTGLASS TO COOL BEFORE HANDLING.
!