34
YORK INTERNATIONAL
If the
refrigerant level sensor
output ever goes to
greater than 4.4VDC,
WARNING–REFRIGERANT LEVEL OUT OF RANGE
is displayed and the level control actuator is driven open
until the level is within range. When within range, the
warning message is automatically cleared and automatic
operation returns.
The refrigerant level control is optional. Therefore, the pro-
gram operation described here must be ENABLED on
those units so equipped and DISABLED on all other
units using the PROGRAMMING procedure below.
MANUAL OPERATION
Manual operation of the variable orifice is allowed in SER-
VICE mode if
manual level control
is selected using
the
programming
procedure below. The PRE-ROTA-
TION VANES manual control keys are used to perform
the open, close, hold and auto function for the variable
orifice when
manual level control
is selected. Either
manual level control or manual control or manual vane
control can be selected using the procedure below. When
manual level control
is selected, the pre-rotation vanes
keys cannot be used to control the vanes. After the ser-
vice technician has completed any
manual level con-
trol
operation, the control center should be returned to
manual level control
using the procedure below.
To determine if manual level control or manual vane con-
trol has been selected, press the display data key.
MANUAL LEVEL CONTROL ALLOWED
or
MANUAL VANE OPERATION ALLOWED
is displayed as one of the scrolled messages.
If manual level control is selected and the control is se-
lected and the control center is operating in SERVICE
mode,
SYSTEM RUN—AUTO LEVEL CONTROL
is displayed unless an OPEN command is given, then
SYSTEM RUN—LEVEL VALVE OPENING
is displayed.
SYSTEM RUN—LEVEL VALVE CLOSING
is displayed when a close command is given.
FIXED POSITION OPERATION
It might be necessary to operate the chiller with the vari-
able orifice in a fixed position. This could be necessary
until a replacement component arrives, if there is a failure
of a refrigerant level control component.
To operate the orifice in a fixed position, enable
manual
level control
using the PROGRAMMING procedure
below. Then, in service operating mode, use the OPEN
and CLOSE vanes keys as described above under
manual operation
to drive the orifice to the desired po-
sition. When the desired position is achieved, press the
HOLD key. This maintains the orifice at the desired po-
sition. Return to
local
or
remote
mode. The open and
close outputs to the orifice are now disabled and it will
remain stationary.
To return to automatic operation, enter
service
mode and
press the AUTO key. Then return to
local
or
remote
mode as desired.
NOTE: For programming setpoints refer to YORK ser-
vice manual, 160.60-M1. Programming is to
be done only by a qualified YORK service
mechanic.
SELECTION OF MANUAL SPEED OR MANUAL VANE
CONTROL (VANE/SPEED TOGGLE KEY)
1. You must be in
SERVICE
mode.
2. Enter Access Code (
9 6 7 5
).
3. Press
ENTER
.
4. Press
PROGRAM
.
5. Press
VANE/SPEED TOGGLE
key.
6. Select 0 = for Vane Position
1 = for Engine Speed
2 = for Level
7. Press
ENTER
after selecting 0, 1, or 2.
8. Press
INCR
or
DECR
keys as desired.
Below is a procedure which will allow you to look at your
changes (vane, engine, speed, level) while standing in
front of the panel. Your changes will be viewed on the
YORK Micro Panel display.
1. You must be in
SERVICE
mode.
2. Enter access code
9 6 7 5
.
3. Press
ENTER
.
4. Press
PROGRAM
PROGRAM MODE, SELECT SETPOINT
5. Press
VANE SPEED TOGGLE
key.
MAN. CONTROL
÷
__ (0=VANE, 1=ENGINE, 2=LEVEL)
6. Select: 0 = Vane Position
1 = Engine Speed
2 = Level
7. Press
ENTER
after selecting 0, 1, or 2.
PROGRAM MODE, SELECT SETPOINT
