| Document type | Service Information Letter |
|---|---|
| Document number | SI0466 |
| Equipment | YLAA Scroll Chiller |
| Brand | YORK |
| File size | 1.5 MB |
Fault codes in this document
ABB AYK550 VFD Drive Not Responding Fault
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| Drive not responding | Fault appearing on the screen for the ABB AYK550 Variable Frequency Drive (VFD) installed on Air-Cooled Chillers (YLAA, YVAA, YVFA). | This fault may be due to the heatsink fan being jammed or failure within the VFD. If the drive still shows the fault after the heatsink fan check, the drive has other damage and must be replaced. | Prior to condemning the VFD, confirm the heatsink fan has not failed. The heatsink fan is located on the back side of the VFD enclosure behind the rain hood assembly. Make sure unit is deenergized and locked out prior to performing steps following JCI procedures for working on electrical equipment. Loosen and remove the six screws holding the rain hood in place (retain screws and foam seal for reassembly) and remove the rain hood assembly. At the top of the VFD, pull the lever on the plastic fan grill guard so the grill guard and fan rotate and lift out of the VFD (do not remove too far, as the wire is attached inside the VFD). Follow the fan wire and disconnect it where it connects into the VFD. Energize the unit and follow procedures within the chiller controls panel to power the VFD. If the drive powers up normally, showing voltage, amperage, and Hz on the screen, then the fan has failed and requires replacement — do not continue to run the VFD with the cooling fan disconnected as the VFD will overheat and fault. Review the nameplate label on the side of the ABB VFD for part number and voltage to determine the correct replacement fan: 026-52721-000 for R1 & R2 575V frame VFD, 026-52722-000 for R2 & R3 frame VFD, or 026-52723-000 for R4 frame VFD. Remove the faulty cooling fan from the fan grill guard (do not damage retaining clips), connect wiring to the new cooling fan, install grill guard with fan into the VFD, and install the rain hood with the six previously removed screws, verifying the foam seal is in good condition and properly compressed. If the drive still shows the "Drive not responding" fault, the drive has other damage and must be replaced. | 1 |
Every row above cites the page of this document it came from, and each one is re-read against that page by an automatic check before publication.
Manufacturer document, published here as reference material for equipment we supply. The original lives at docs.johnsoncontrols.com. The rights holder may ask us to take it down — we will.