Installation Manual
Rinnai Tankless Rack System (TRS) Installation Manual     53 
 Connect Water Heaters 
12 
 OUT 
IN  
OUT  
Cascade 
Cable 
With use of cascade cable(s) (oponal accessory purchased separately) up to 24 water heaters can be electronically 
connected. This connecon will rotate water heater operaon order to ensure equal usage among the enre system 
and enables all water heaters connected to modulate operaon and funcon as one hot water source.  
Cascade Cable Required: 
•  Cable length: 26  (8 m) 
 OR 
•  Cable Length: 10  (3 m) 
•  One cable required for each 
water heater. 
•  Includes 1 cable and 2 cascade jumpers. 
Primary
Secondary 1
For proper operaon, do not combine dierent models 
with cascade communicaon. 
1.  Connect one end of the Cascade Cable to the “Cascade 
OUT” accessory port on the PCB. 
2.  Connect the other end of the cascade cable to the 
“Cascade IN” accessory port on the PCB of the next 
water heater. 
3.  Repeat steps 1 and 2 for each subsequent water 
heater in the system. 
4.  Connect the “Cascade Jumper” (Included with the 
cascade cable) to the open accessory ports. 
5.  Proceed to “Programing Cascade Communicaon” on 
the following page. 
Primary 
PCB 
Secondary 1 
PCB 
Secondary 2
-23 
Secondary 2 
PCB 
IN  
Cascade 
Jumper 
Cascade 
Jumper 
Accessory 
Port 
Location 
Cascade IN 
Cascade OUT 
Cascade Cable Assembly 










