Document revision history
   
 
 
 
RTU Open v3    CARRIER CORPORATION ©2019  
Installation and Start-up Guide    All rights reserved 
  107 
 
 
Important changes to this document are listed below. Minor changes such as typographical or formatting errors are not 
listed. 
 
 
Troubleshooting > To get the serial 
number 
As of 2019, serial numbers are laser-etched on the circuit 
board 
Appendix A > Service Configuration 
Fixed error in System Fire / Smoke description  
 
Corrected DCV Max Vent Damper Pos percent 
Removed limit on Setpoint Adjustment Range 
Appendix A > Service Configuration 
VFD Speed Test - correction. Only Service Test muast be set to 
Enable. Previously, it stated that both Service Test and Fan Test 
What is the RTU Open controller? 
J1 Input 5 (SMK) wire color corrected from gray to blue. 
Wiring devices to the RTU Open's 
Rnet port 
Removed star configuration from the first paragraph. 
What is the RTU Open controller? 
In the drawing, corrected wire color for J1 Input-5 to blue from 
dark gray 
Added surge CAUTION to Protection specification. 
 
To wire the Wireless Adapter for 
wireless sensors 
Added warning that the Wireless Adapter must be mounted on 
the inside of the building 
Removed SPT sensors from space temperature sensors. 
Wiring inputs and outputs 
Removed SPT sensor from Input wiring table, added TruVu™ ET 
Display, and referred user to the device's Installation and Start-
up Guide. 
 
Wiring devices to the RTU Open's 
Rnet port 
Combined overview and wiring on the zone sensors and 
touchscreen devices. Added TruVu™ ET Display. 
Reworded Rnet port specification and added power supplied by 
Rnet port. 
Reworded Protection specification and added first paragraph.  
Added information that the unit must be shut down before 
running Service Test and how to verify that. 
 
Economizer 
Added information on Fault Detection & Diagnostics 
 
Corrected total number of supported wireless sensors to 5. 
Added the load impedance when AO channels are used in a 
voltage output type application. 
Sequence of Operation  - Cooling 
Correction - OAT added to cooling algorithm re:economizer 
Document revision history