FORM 160.55-O1 (920)
103
YORK INTERNATIONAL
flush the heat-exchanger by reversing the two rubber
hoses which supply condenser water to-from the
heat-exchanger. If the rust cannot be back-flushed,
the heat-exchanger might have to be replaced.
•
Low Condenser Flow
– The VSD system requires
8 feet of pressure drop across the heat exchanger
to maintain adequate GPM. If the pressure drop is
less than 8 feet, it will be necessary to correct the
flow problem or add a booster pump as is applied
on retrofit chillers.
“
VSD – INVALID CURRENT SCALE
SELECTION
”
Since the part number of the VSD Logic Board is the
same on all horsepower sizes, the position of Program
Jumpers tells the Logic Board the size of the VSD
employed. This allows the VSD to properly scale the
output current. If the Jumper configuration is invalid, a
shutdown is performed and this message is generated.
“
VSD – LOW PHASE A INVERTER HEATSINK
TEMPERATURE
”
(Style D VSD)
A Heatsink temperature sensor indicating a temperature
<37°F will cause the chiller to shut down and display
this message. In most cases, the problem will be an open
thermistor or broken wiring to the thermistor. The nor-
mal thermistor resistance is 10K ohms at 77°F.
“
VSD – LOW PHASE B INVERTER HEATSINK
TEMPERATURE
”
(Style D VSD)
See “Low Phase A Inverter Heatsink Temperature”
message above.
“
VSD – LOW PHASE C INVERTER HEATSINK
TEMPERATURE
”
(Style D VSD
See “Low Phase A Inverter Heatsink Temperature”
message above.
“VSD – LOW CONVERTER HEATSINK
TEMPERATURE”
If VSD part number is 371-02767-XXX (60 Hz) or
371-03700-XXX (50 Hz), a heatsink temperature sensor
indicating a temperature of <37ºF will cause the chiller
to shutdown and display this message. In most cases,
the problem will be an open thermistor or broken wir-
ing to the thermistor. The normal thermistor resistance
is 10K ohms at 77ºF.
“VSD – LOW PHASE A INVERTER BASEPLATE
TEMPERATURE”
(VSD part number 371-03789-xxx (503HP 60Hz; 419HP
50Hz (Flash Memory Card version C.MLM.02.04.xxx
and later)
The chiller has shutdown because the baseplate tem-
perature has decreased to <37 ºF.
“VSD – LOW PHASE B INVERTER BASEPLATE
TEMPERATURE”
(VSD part number 371-03789-xxx (503HP 60Hz; 419HP
50Hz (Flash Memory Card version C.MLM.02.04.xxx
and later)
The chiller has shutdown because the baseplate tem-
perature has decreased to <37 ºF.
“VSD – LOW PHASE C INVERTER BASEPLATE
TEMPERATURE”
(VSD part number 371-03789-xxx (503HP 60Hz; 419HP
50Hz (Flash Memory Card version C.MLM.02.04.xxx
and later)
The chiller has shutdown because the baseplate tem-
perature has decreased to <37 ºF.
“VSD – LOW INVERTER BASEPLATE TEM-
PERATURE”
(Applicable to VSD with part number 371-02767-
XXX (60 Hz) or 371-03700-XXX (50 Hz))
(Requires Flash Memory Card version C.MLM.-
02.02A.xxx and later)
A baseplate temperature sensor indicating a temperature
of <37ºF will cause the chiller to shut down and display
this message. In most cases, the problem will be an open
thermistor or broken wiring to the thermistor. The nor-
mal thermistor resistance is 5K ohms at 77ºF.
“
VSD – PRECHARGE – LOW DC BUS
VOLTAGE
”
During Pre-charge, the DC link must be equal to or
greater than 50VDC (41VDC for 50 Hz) within ½ second
and 500VDC within 15 seconds after the Pre-charge re-
lay is energized. If this condition is not met, a shutdown
is performed and this message is generated.
“
VSD – LOGIC BOARD PROCESSOR
”
This shutdown is generated if a communications prob-
lem occurs between the two microprocessors on the
VSD Logic Board.
2