Carrier 69NT40-561-019, Operation And Service Manual

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7–21 T-359
7. Leak check and evacuate low side of unit as applicable. Refer to Section 7.3.4 .
8. Open service valves.
7.16 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
Table 7–1 . Capacity mode (CAP) allows alignment of the economizer
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
override(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, override
function is automatically terminated and the valves return to normal machinery control. To operate the override, do
the following:
a. 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.
b. Press the ENTER key. The left display will show a test name alternating with the test setting or time remain-
ing. Use an ARROW key to scroll to the desired test. Press the ENTER key and SELCt will appear in the left
display.
c. 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 Table 7–1 .
d. 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.
e. The above described sequence may be repeated during the timer cycle to change to another override.
Table 7–1 Valve Override Control Displays
Left Display
Controller Communications Codes
(Right Display)
Setting Codes
(Right Display)
Cd 41/SELCt
tIM
(Override Timer)
0 00 (0 minutes/0 Seconds)
In 30 second increments to
5 00 (5 minutes/ 0 seconds)
PCnt
(% Setting - DUV Capacity Modulation)
AUtO
(Normal Machinery Control)
0
3
6
10
25
50
100
EEV
(% Setting - Electronic Expansion Valve)
AUtO
(Normal Machinery Control)
CLOSE (Closed)
0
3
6
10
25
50
100
CAP
(Capacity Mode)
AUtO (Normal Control)
Std UnLd (Economizer = Closed)
ECOn (Economizer = Open)