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FORM 160.87-OM1
ISSUE DATE: 8/24/2018
JOHNSON CONTROLS
36
SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION
REFRIGERANT LEVEL CONTROL SCREEN
LD22046
FIGURE 11 - REFRIGERANT LEVEL CONTROL SCREEN
OVERVIEW
This screen displays a cutaway view of the chiller con-
denser, along with the liquid refrigerant level sensor
and the flow control valve. All setpoints relating to
the liquid level control are maintained on this screen.
Through animation, the variable orifice position is dis-
played. In addition, the refrigerant flow control valve
(variable orifice) can be manually operated.
Requires a login access level of SERVICE.
DISPLAY ONLY
Condenser Refrigerant Level
Displays the present position of the liquid level. The
refrigerant level is animated in the cutaway view of
the condenser. The actual level of the refrigerant in the
tank does not match the percentage displayed in the
Level Control Valve Command box. The actual levels
versus the displayed percentages are as follows:
TABLE 2 - CONDENSER LEVEL POSITION
ACTUAL LEVEL
CONTROL VALVE
COMMAND %
0% to 15% 50%
16% to 31% 60%
32% to 47% 70%
48% to 63% 80%
64% to 79% 90%
79% 100%
Subcooler Effectiveness
The Subcooler Effectiveness is evaluated with the fol-
lowing calculation and compared to a high and low
limit. (Cond Sat Temp-Drop Leg Ref Temp)/(Cond Sat
Temp-Entering Cond Liq Temp). This value is typi-
cally near 0.8 at design conditions.
Level Control State
Indicates one of the following states the level control
routine is in: Manual, Inactive, Startup Hold, Setpoint
Ramp, PID Control, Hold.
Startup Delay Remaining
The level valve is held at the starting position until
15 seconds after start to allow the system to stabilize.
Then the valve position is controlled by the PID loop.