Application Note: Carrier Split System Control with the CCU

Current Standard Solution:

75F is able to control compatible single-zone or multi-zone Carrier split systems by using the KSAIC0301230 24V interface kit for ductless and hybrid solutions.  

Scenario:

There are multiple Carrier split systems retrofitted in a building with an existing 75F system. 

How does it work:

The profile on the CCU is set to VVT-C stagged RTU and set up for single-stage operation 1- Cool 1-Heat 1-Fan. The control mote (CM) is then wired to the 24v interface module. The indoor and outdoor units are also wired to the 24v interface module. If wired correctly, the interface module will display 00- Interface successfully powered up and system in standby. When the CCU calls for conditioning the interface module will display  01-Cooling Operation, 02- Heating Operation, and 03- Fan Only Operation. 

Wiring and Configuration :

Note: Please reference the indoor/outdoor unit compatibility chart to verify the KSAIC0301230 24v interface is compatible with your equipment.

https://www.shareddocs.com/hvac/docs/1011/Public/0C/CAR-DLSS-04CC.pdf

https://www.shareddocs.com/hvac/docs/1010/Public/01/01-DLS-043-01.pdf

Please pay close attention to the installation manual for the fan coil unit, outdoor unit, and 24v Interface.

24v Interface Installation Manual  https://ca-manufacturer-documents.s3.amazonaws.com/CarrierDocs/IM-KSAIC03-08.pdf

The communications wiring S1(P) S2(Q) for the indoor and outdoor units to the 24v interface module must be two conductor-stranded 16ga shielded. The connection is polarity sensitive, both shields (bare wire) are twisted together at the interface module and grounded at the indoor and outdoor units. Dip switches SW1-1 and SW1-2 at the interface are set in the ON position all the other dip switches are set to the OFF position. See the wiring detail and configuration below.

CCU Configuration:

Result:

Using a  CCU to control a Carrier split system also allows you to use a ClimaVision VVT zoning application. (Only on ducted fan coils compatible with the KSAIC0301230 24v interface)

Integration with a CCU is a straightforward easily deployable solution suitable for installations where split systems are used instead of a conventional RTU.