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SECTION 33 - SYSTEM CALIBRATION, SERVICE SETPOINTS, AND RESET PROCEDURES
FORM 160.54-M1
ISSUE DATE: 10/25/2019
JOHNSON CONTROLS
JCI COMPANY CONFIDENTIAL
33
evaporator. If ENABLED with the procedure below,
this temperature is displayed on the CONDENSER
Screen as the “Drop Leg Temperature”. It is subtracted
from the Condenser Saturation Temperature to produce
“Sub Cooling Temperature”, also displayed on the
CONDENSER Screen. If the chiller is equipped with
the Drop Leg Refrigerant Temperature sensor, the val-
ues are displayed on the CONDENSER Screen only if
ENABLED with the following procedure:
1. At the keypad, log in at SERVICE access level
using access code 1 3 8 0.
2. Select CONDENSER Screen.
3. Press DROP LEG key.
4.
Use ◄ and ► keys to select Enable or Disable.
5. Press ENTER (
) key.
SMART FREEZE PROTECTION
of this manual. When turned
on, it allows the Leaving Chilled Liquid Temperature
setpoint to be as low as 36°F for water cooling appli-
cations. Along with this feature is a correspondingly
lower Low Water Temperature Cycling Shutdown
threshold and LOW EVAPORATOR PRESSURE
safety shutdown threshold. The Smart Freeze Protec-
tion feature can be turned ON or OFF using the follow-
ing procedure:
1. Shutdown the chiller and wait for completion of
COASTDOWN.
2. At the keypad, log in at SERVICE access level
using access code 1 3 8 0.
3. Select EVAPORATOR Screen.
4. Press SMART FREEZE key.
5.
Use ◄ and ► keys to select ON or OFF.
6. Press ENTER (
) key.
EVAPORATOR REFRIGERANT TEMPERATURE
If the chiller is equipped with an Evaporator Refriger-
ant Temperature sensor, the feature must be enabled with
the procedure below. If not equipped with this sensor, it
must be disabled. If enabled, this temperature is displayed
on the EVAPORATOR Screen, and is also used in the
SMART FREEZE PROTECTION LOW EVAPORA-
TOR PRESSURE safety shutdown threshold calculation,
SECTION 24 - SMART FREEZE PRO-
Use the following procedure to Enable or Disable this
feature:
1. At the keypad, log in at SERVICE access level
using access code 1 3 8 0.
2. Select EVAPORATOR Screen.
3. Press REFRIGERANT key.
4.
Use ◄
and
►
keys to select Enabled or Disabled.
5. Press
ENTER
(
) key.
HOT GAS BYPASS CONTROL
A complete description of the optional Hot gas bypass
Control and the setpoints that affect this control are
provided in
of this
manual. The setpoints are listed below. If the chiller is
equipped with this feature, it must be ENABLED and
the setpoints programmed using the procedure below.
Otherwise, it must be DISABLED. The Hot gas valve
can be manually controlled using the procedure below.
The total lifetime Surge Count can be cleared. Howev-
er, this should NOT be arbitrarily performed! Since the
Pre-Rotation Vanes (PRV) position is used in the Hot
gas control, the PRV position feedback potentiometer
must be calibrated with the procedure below.
Enable/Disable
If the chiller is equipped with the optional Hot gas
bypass Control, operation must be ENABLED. Oth-
erwise, it must be DISABLED. Use the following pro-
cedure:
1. Shutdown chiller and place COMPRESSOR
Start/stop Switch in the Stop-Reset (O) position.
2. At the keypad, log in at SERVICE access level,
using password 1 3 8 0.
3. Select SETPOINTS Screen. From SETPOINTS
Screen, select SETUP Screen. From SETUP
Screen, select OPERATIONS Screen.
4.
Use ◄ and ► keys to select Enable or Disable.
5. Press ENTER (
) key.
Setpoints
The following are the setpoints and range of program-
mable values. The DEFAULT value is shown in paren-
theses. The Default value is the recommended value
and should provide proper operation in most applica-
tions. However, the setpoint can be programmed to oth-
