Issue:
Ed : Chilled Water Flow Interlock Diagnostic
Resolution:
- The UCM logic is powered by the 1T2 and 1T12 transformers.
- An additional 115V power supply is required on terminal strip 1TB2-4 and 1TB2-11.
- This power can be provided by either an optional control power transformer supplied by the factory or a 115 volt power supply provided in the field.
- This voltage supplies power to the A7, A8, and A9 boards for relay switching.
- If there is no voltage present while the UCM is powered, the diagnostic or display mentioned above may appear on the display.
- Please ensure that the flow proving device (flow switch) is connected to module 1U1A7 on TB1-4.
Notes:
Refer to troubleshooting bulletin CGAD-SB-2B for additional information
Other Question/Problem/Cause Statements:
- ED, Chilled water flow interlock diagnostic.
- ED or A100 displayed or alternating at start up
- Flashing ED and A100
- Getting an Ed Chilled water flow interlock diagnostic.
Facts:
- Water-Cooled Chiller (PBL) (CGWD, CGWE, CGAD, CGAE, CCAD, CCAE)
- AIR-COOLED CHILLERS
- Wiring has been checked and is ok.
- Jumper has been put across the flow switch and chiller still gets a diagnostic.
- Jumper has been put across 1TB4-4 & 5 on the A7 module (chilled water flow switch input) and chiller still shows diagnostic.
Document Identifier: DOC-81923
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.