| Document type | Service Information Letter |
|---|---|
| Document number | SI0256 |
| Equipment | YMC2 Magnetic Bearing Centrifugal Chiller |
| Brand | YORK |
| File size | 0.3 MB |
Fault codes in this document
Expansion I/O – Serial Communication Fault
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| Serial Communication Fault | Loss of serial communications with the Expansion I/O LTC I/O Board. In this software version the fault includes a timeout (previously it did not). | Communications from the LTC I/O Board are NOT received for 3 consecutive attempts with a 2 second timeout between attempts; the fault occurs if communications is NOT established within 6 seconds of the first attempt. | The fault is released automatically when a valid response is received from the LTC I/O Board. | 1 |
Condenser and Evaporator Flow Faults
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| CONDENSER – FLOW SWITCH OPEN | Cycling fault. In this software version this Standard Soft Shutdown fault has been changed to a Fast Soft Shutdown. | Set when the Condenser Flow Switch is open for 5 seconds when either the Chiller State is Running or the Chiller State is Soft Shutdown. | The fault will be released when the Condenser Flow Switch closes, or when the Run Permissive is False and the Chiller State is Stopped. | 2 |
| CHILLED LIQUID – FLOW SWITCH OPEN | Cycling fault. In this software version this Standard Soft Shutdown fault has been changed to a Fast Soft Shutdown. | Set when the Chilled Liquid Flow Switch is open for 5 seconds when any of the following are true: the Chiller State is Running; the Chiller State is Soft Shutdown; the Chiller State is MBC Startup and the time in the MBC Startup State is greater than 45 seconds. | The fault will be released when the Chilled Liquid Flow Switch closes, or when the Run Permissive is False and the Chiller State is Stopped. | 2 |
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.