Issue:
Johnson Controls (JCI) VFD drive fault problem and the VFD must be bypassed directly to the fan motor.
Resolution:
RTAC Low/Wide Ambient Chillers
- The drive fan can be run directly off the contactor by connecting the fan motor directly to the drive 3-phase connections.
- This will generate a VFD drive fault diagnostic that can be bypassed as shown in the next paragraphs. This can be accomplished for both drives on both circuits if the owner chooses to run the circuit without the frequency drive or if the frequency drive is defective.
- For two compressor RTAC chillers, the 1U3 Dual Inverter Interface LLID needs to be jumpered across J2-2 & J2-3 for circuit one or J2-5 and J2-6 for circuit two. When this is done the drive fault will not be reported and the circuit will be allowed to run without the VFD wired in.
- For 3 and 4 compressor RTAC chillers, install jumpers as described above in Panel 1 on the 1U3. For panel 2, install jumpers on the same terminals on the 2U3 Dual Inverter Interface.
Other Question/Problem/Cause Statements:
- Getting a VFD drive fault problem and the VFD has been bypassed directly to the fan motor.
- How do I bypass my Drive?
- How do I wire the fault code input after removing the drive on one circuit?
- Can I run one circuit on a VFD and not on the other?
- VFD drive fault error.
Facts:
- RTAC
- Air-Cooled Chiller (Pueblo) (RTAC)
Document Identifier: DOC-96531
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.