Carefully make all regular preliminary and running system checks. Perform a Control Test
before start-up. If the compres sor oil level appears abnorma lly high, the oil may have a bsorbed
refrigerant. Make sur e t hat the oil temperatur e is above 140 F (60 C) or cool er refrigerant
temperature plus 50° F (27° C).
Cold Weather Operation
When the entering condenser water drops very low, the operator should automatically cycle
the cooling tower fans of f to keep the temperatur e up. Piping may also be ar r an ged to bypass
the cooling tower. The PIC c on trols have a low limit tower fan relay (PR3) th at can be used to
assist in this control.
Manual Guide Vane Operation
Manual operation of the guide vanes in order to che ck control operatio n or control of the
guide vanes in an eme rgency operation is possible by o verriding the targ et guide vane pos ition.
Access the Status01 table on the LID and highlight

TARGET GUIDE VANE POSITION

. To
control the position, enter a percentage of gu ide vane opening that is des i red. Zero percent is
fully closed, 100% is fully open. To re lease the gui de vanes to AU TOMATIC mode, press the
RELEASE softkey.
Note: Manual control will incre ase the guide vanes an d override the pulld own rate during start-
up. Motor current above t he electrical deman d setting, capacit y ov er r id es, and chilled
water below control po int will override the man ual target and close th e guide vanes. For
descriptions of capacity overrides and set points, see the Controls section.