JOHNSON CONTROLS
24
FORM 160.67-O2
ISSUE DATE: 10/9/2020
SECTION 2 - PRE-STARTUP AND SYSTEM OPERATING PROCEDURES
Test the operation of the standby pump the same as de-
scribed above.
If the chiller is equipped with an optional
standby pump,
in the automatic mode, the
hotwell pumps will be switched-over (at
each chiller start) to share operational
time. If the lead pump fails to start or
fails while the chiller is operating, toggle
to standby pump will be done automati-
cally. If both pumps fail, the chiller will
not be allowed to start and will shutdown
if operating.
The lead hotwell pump will be started
automatically 50 seconds after a start is
initiated if condenser cooling liquid flow
is verified.
PREPARE THE STEAM CONDENSER
VACUUM PUMPS
Depending on the length of time the pump
has been idle or in storage, it may be
charged with a rust inhibited 50% ethyl-
ene glycol solution. This must be properly
drained prior to operating the pump.
Prior to operating the pump, the housing should be
drained of any storage solution. Remove the screw
plug on the pump cover and allow the liquid to run out.
When draining, rotate the motor occasionally in the op-
posite direction to the running direction (see direction
arrow on the casing) by hand at the external fan until
no more liquid runs out.
Reinstall the drain plug and remove the vacuum gauge
to prime the pump housing with approximately 3.25
quarts (3 liters) of water via the vacuum gauge port.
Do not start the pump if the pump cham-
ber is full, since this could result in the
breakage of a blade or the impeller drive
shaft. If the pump motor fails to start
within 5 seconds after the contactor is
energized, the sealing water solenoid is de-
energized to stop the flow of water into the
chamber. After a pump motor failure, it is
recommended that some water be drained
from the chamber to ensure a safe restart.
Open the main isolation valve at the edge of the base
frame and all valves in the sealing water line of the
selected pump and the standby pump (if supplied).
Ensure that the Vacuum Pump Motor Protector Over-
load switches are in the OFF position.
BUMP test the vacuum pump and standby pump (if
supplied) motors for proper rotation. The easiest way
to do this is to first put the selected pump in the manual
mode. While viewing the VACUUM SCREEN on the
OptiView™ Control Center, use the vacuum pump,
Pump Mode key to put the selected pump in the Manu-
al mode. In the Manual Mode, if the pump motor does
not start within 5 seconds after the pump start is initi
-
ated an alarm is sounded. Since the standby pump will
not start (Overload switch is OFF), the Mode key will
revert back to Auto after 5 seconds and the Pump Run
Output will go off. When a pump start is initiated, the
sealing water solenoid valve is energized and when the
flow switch closes, the Run Output LED is illuminat-
ed. Place the selected vacuum pump motor protector
overload switch in the Power Panel in the ON posi-
tion (within 10 seconds) and immediately back to the
OFF position after the pump starts. The vacuum pump
should rotate as indicated by the arrow on the pump. If
pump runs backwards, interchange two wires.
Even though it is not necessary to prime
the vacuum pumps, they must not be run
dry after the initial startup. Normally the
flow switch will prevent this from hap
-
pening. However, the drain line from the
separator should be checked after the
initial startup and periodically thereafter
to verify that the sealing water is present.
If no water is coming out of the vacuum
pump separator when the pump is operat-
ing, stop the pump immediately!
Place the vacuum pump motor protector overload
switch in the power panel in the ON position. While
viewing the VACUUM SCREEN on the OptiView™
Control Center, use the vacuum pump, Pump Mode
key to manually start the selected pump. When a pump
start is initiated, the sealing water solenoid valve is en-
ergized. As soon as the flow switch contacts close, the
pump motor is started. In the Manual mode, if seal-
ing water flow is not established within 10 seconds af-
ter the pump start is initiated, an alarm is sounded the
mode key reverts back to Auto, and the Run Output
goes OFF. Adjust the sealing water flow to the pump
using the hand valve (downstream of the solenoid
valve) to obtain a slight vacuum reading on the gauge
down stream of the valve. When the desired vacuum