7.25 Valve Override Controls; Table 7-1 Valve Override Control Displays - Carrier PrimeLINE 69NT40-561-200 Operation And Service Manual

7.25 VALVE OVERRIDE CONTROLS

Controller function code Cd41 is a configurable code that allows timed operation of the automatic valves for trou-
bleshooting. Test sequences are provided in
solenoid valve in the standard and economized operating configurations. DUV Capacity Modulation% Setting
(PCnt) and Electronic Expansion Valve (EEV) allows opening of the digital unloader valve and electronic expansion
valve, respectively, to various percentages. If the unit is equipped with an LIV, the Liquid Valve Setting allows the
LIV to be automatically controlled, or manually opened and closed.
The Override Timer (tIM) selection is also provided to enter a time period of up to five minutes, during which the over-
ride(s) are active. If the timer is active, valve override selections will take place immediately. If the timer is not active,
changes will not take place for a few seconds after the timer is started. When the timer times out, the override function
is automatically terminated and the valves return to normal machinery control. To operate the override:
1. Press the CODE SELECT key then press an Arrow key until Cd41 is displayed in the left window. The right
window will display a controller communications code.
2. Press the ENTER key. The left display will show a test name alternating with the test setting or time remaining.
Use an Arrow key to scroll to the desired test. Press the ENTER key, SELCt will appear in the left display.
3. Use an Arrow key to scroll to the desired setting, and then press the ENTER key. Selections available for
each of the tests are provided in
4. If the timer is not operating, follow the above procedure to display the timer. Use an Arrow key to scroll to the
desired time interval and press ENTER to start the timer.
5. The above described sequence may be repeated during the timer cycle to change to another override.
LEFT DISPLAY
Cd 41/SELCt
T-362
Table 7–1. Capacity mode (CAP) allows alignment of the economizer
Table 7–1.
Table 7–1 Valve Override Control Displays
CONTROLLER COMMUNICATION
CODES (RIGHT DISPLAY)
tIM
(Override Timer)
PCnt
(% Setting - DUV Capacity Modulation)
EEV
(% Setting - Electronic Expansion Valve)
CAP
(Capacity Mode)
SETTING CODES (RIGHT DISPLAY)
0 00 (0 minutes/0 Seconds)
In 30 second increments to
5 00 (5 minutes/ 0 seconds)
(Normal Machinery Control)
(Normal Machinery Control)
ECOn (Economizer = Open)
7–28
AUtO
0
3
6
10
25
50
100
AUtO
CLOSE (Closed)
0
3
6
10
25
50
100
AUtO (Normal Control)
Std
UnLd
(Economizer = Closed)