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JOHNSON CONTROLS
FORM 201.21-NM1 (1223)
LD10605
PROGRAM
KEY
PROGRAM KEY
PROGRAM KEY OPERATION
Various operating parameters are programmable by the
user. These are modied by pressing the PROGRAM
key and then the (ENTER) key to enter Program
Mode. A listing of the limits of the programmable values
is found below. Note that the Imperial units are exact
values, while Metric units are only approximate.
The ▲ and ▼ (ARROW) keys are used to scroll through
the user programmable values. A value may be changed
by keying in the new value and pressing the (ENTER)
key to store the new value in memory. The cursor will be
displayed on the screen when a number key is pressed.
The rst line of each message will indicate the chiller
default (DEF) value), lowest acceptable programmable
value (LO), and highest acceptable programmable value
(HI). The user programmable value is programmed on
in the second line of the message.
When the PROGRAM Key is rst pressed, the fol-
lowing display will appear indicating the user is in the
program mode:
Pressing the (ENTER) key again will display the rst
programmable selection.
Suction Pressure Cutout
PROGRAM MODE XXXX
PRESS ENTER KEY TO CONTINUE
The suction pressure cutout is protects the chiller from
a low refrigerant condition. It also helps protect from a
freeze-up due to low or no chilled liquid ow. However,
it is only a back-up for a ow switch and cannot protect
against an evaporator freeze under many conditions.
This cutout is programmable and should generally be
programmed for 24PSIG (1.65 Barg) for chilled water
cooling.
The cutout is programmable between 24.0 – 36.0 PSIG
(1.65 – 2.48 Barg) in the Water Cooling mode and 5.0
– 36.0 (0.34 – 2.28 Barg) in the Glycol Cooling mode.
The default value for both modes will be 24.0 (1.65
Barg) PSIG.
PROGRAM ◄DEF XXXXX LO XXXXX HI XXXXX
SUCTION PRESSURE CUTOUT = XXX.X PSIG
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