York YK-EP Operation And Maintenance Manual page 73

Table 60: Programmable
Button Access level
Stall Wait
Service
Time
Open Pulse Service
High Limit Service
Low Limit Service
Table 61: Navigation
Button Access level
Home Service
Economizer
Service
VGD
YK-EP Style B Centrifugal Chiller
Description
(0.5 to 15 minutes, Default 10 minutes)
After the VGD control detects a stall and enters Stall Wait State. It
will wait for 10 minutes before going into the probing (Open) mode.
(1 to 5 seconds, Default 2 seconds)
In the Probing State, VGD opens in pulse. The pulse length is 10
seconds. The VGD will open for 2 seconds and hold during the rest
of the pulse period (8 seconds). This pulse repeats the 10 second
pulse over and over again until the stall voltage is higher than the
high limit.
(0.35 to 1.20V, Default 0.8V)
If stall voltage is higher than high limit of 0.8V, the VGD control
enters the stall react state that closes the VGD. It will keep closing
the VGD until stall volt is lower than the low limit 0.5V.
(0.30 to 0.79V, Default 0.50V)
When stall voltage is lower than low limit, the VGD control enters the
Wait state.
Description
Returns user to HOME Screen.
Pressing this button will return to the Economizer VGD screen.
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