Summary:
The Copeland Scroll Digital Compressor Controller is applied as part of Trane Creative Solutions digital scroll compressor modification. This control is the interface between the compressor and the Trane controller (typically an MP or UC programmable controller) and provides control, protection and diagnostics for the compressor. When a fault is detected, the controller employs a diagnostic LED to help assist technicians with troubleshooting compressor faults.
The most common fault related to this application is flash code 3, compressor protector trip. The goal of this article is to assist technicians with understanding of possible causes of the fault.
See the Application Engineering Bulletin link below for an in-depth overview of possible fault codes, as well as functions and features not covered in this article.
Resolution:
NOTICE: Before cycling power, check for fault codes on the digital scroll controller and the compressor protection module (located in the compressor junction box)! Whenever power is cycled off and on, the current flash code and all internal counters are reset.
Flash Code 3 - Compressor Protector Trip
This indicates the Trane controller is requesting for the compressor to run, but the compressor is off and no current detected.
Possible Cause: Compressor protection module tripped, compressor discharge line high limit, high/low pressure cutouts, circuit breaker trip, open contactor coil, and loose wire/connection.
See the supplied control diagrams as well as as-built documents for more information on compressor safety circuit wiring.
For RAUJ products, see RAUJ - Reset Relay Troubleshooting (R410A).
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.