On the display
ACC Surge Detected appears on the panel as an LED, not as a lockout message. It is one of the VGD screen indications and appears on the VGD screen, the variable geometry diffuser screen and the surge map screen. The LED illuminates momentarily — it lights only while the surge event is present and then goes out on its own. It exists only on chillers equipped with a VSD or MV VSD: document SI0252 states that the LED is added to the VGD screen when the Motor Drive Type setpoint is set to VSD and the Motor Communications Protocol setpoint is set to MODBUS. Document 160.54-O1 ties the LED to software version C.OPT.01.19.307 and later on one screen and to C.OPT.01.23.307 and later on the variable geometry diffuser screen.
What it means
The LED signals that a surge was detected by the ACC function in the Microboard while the drive was running at less than maximum frequency. It is therefore the below-maximum-speed surge indication: it only reports surge events that occur while the drive operates below maximum frequency. The manuals list it among display-only fields, and SI0252's fault table attaches no action to it. The screen that carries the LED notes that there are no programmable setpoints on it. The related ACC Surge Count field displays the total number of surges detected while the drive is running at less than maximum frequency, so repeated momentary indications can be compared against that running total.
Work on this equipment should only be done by properly trained personnel who are qualified to work on this type of equipment.
Why it appears
Running at less than full speed
— SI0252's fault table gives this as the cause of the indication; the LED only illuminates for surges detected while the drive operates below maximum frequency.
Setpoints and thresholds
- The LED is only displayed if the chiller is equipped with a VSD or MV VSD (160.76-O2, 160.54-O1, 160.95-O2).
- Per SI0252, the LED is added when the Motor Drive Type setpoint is set to VSD and the Motor Communications Protocol setpoint is set to MODBUS.
- 160.54-O1 ties the LED to software version C.OPT.01.19.307 and later (VSD in Modbus Protocol Configuration only, or MV VSD) and, on the variable geometry diffuser screen, to C.OPT.01.23.307 and later.
- The screen carrying the LED has no programmable setpoints (160.76-O2).
- Modbus data points (160.76-O2): ACC Surge Detected = 8236, ACC Surge Count = 2849.
Questions engineers ask
What does ACC Surge Detected mean on a York YK chiller?
It is a display-only LED indicating that a surge was detected by the ACC function in the Microboard while the drive was running at less than maximum frequency. It illuminates only momentarily during the event.
Why don't I see ACC Surge Detected on my chiller?
It is only displayed on chillers equipped with a VSD or MV VSD. Per SI0252, the LED is added when the Motor Drive Type setpoint is set to VSD and the Motor Communications Protocol setpoint is set to MODBUS.
Does ACC Surge Detected shut the chiller down?
No action is attached to the LED in SI0252's fault table, and the manuals list it among display-only fields; no shutdown or reset behaviour is described for this indication.
What is the Modbus address for ACC Surge Detected?
160.76-O2 lists ACC Surge Detected at Modbus data point 8236, with ACC Surge Count at 2849.
Messages next to this one
Source
Written from the manufacturer's manuals for the YORK YK; every number and designation on this page is checked against them before publication. The row of the manual this message comes from:
All YORK YK messages: fault codes · YORK YK documentation · YORK manuals