York MAXE OPTIVIEW YK, Service Instructions Manual

Page: 97 / 180

FORM 160.54-M1(503)
97
YORK INTERNATIONAL
OIL HEATER OPERATION
On chillers equipped with the oil pump VSD, the oil
heat er is controlled by the Microboard via I/O Board
The connection to the I/O Board is determined by the
chiller style and compressor type as follows:
•
TB1-34 - Style D and E chillers with “G”, “H” or
“J” compressors
•
TB1-64 - Style E chillers with “P” compressors and
all Style F and later chillers.
When the oil pump is not operating, the heater is turned
on and off to maintain a target value of 50ºF above the
Condenser Saturation Temperature. If the calculated tar-
get value is > 160ºF, the target value de faults to 160ºF.
If the calculated target value is < 110ºF, it defaults to
110ºF. When the temperature de creas es to 4ºF below
the target value, the heater is turned on; it is turned off
at 3ºF above the target.
To prevent overheating the oil in the event of an
OptiView Control Center failure, thermostat 1HTR
opens at 180ºF.
FIG. 53 – OIL PUMP VARIABLE SPEED DRIVE (VSD)
28782A
OIL PUMP VSD
15