Installation Manual
2  Rinnai Tankless Rack System (TRS) Installation Manual
READ AND SAVE 
THESE INSTRUCTIONS 
Thank you for purchasing a Rinnai Tankless Rack 
System (TRS). This manual provides instrucons on 
installing a TRS. For specic quesons on the Rinnai 
Tankless Water Heaters, refer to the “Rinnai Tankless 
Water Heater Installaon and Operaon Manual” 
supplied with each water heater in the rack system. 
Read this manual completely before installing the TRS.  
To The Installer 
•  It is recommended that a trained and qualied 
professional who has aended a Rinnai 
installaon training class complete the installaon. 
Improper installaon may void the warranty.  
•  The trained and qualied professional should have 
skills such as: 
−  Gas line sizing 
−  Connecng gas lines, water lines, valves, and 
electricity 
−  Knowledge of applicable naonal, state, and 
local codes 
−  Installing venng through a wall or roof 
−  Training in installaon of tankless water 
heaters. Training on Rinnai Tankless Water 
Heaters is accessible at 
www.trainingevents.rinnai.us. 
•  Read all instrucons in this manual before 
installing the TRS. The TRS must be installed 
according to the exact instrucons in this manual.  
•  In addion to this manual, you will also need the 
“Rinnai Tankless Water Heater Installaon and 
Operaon Manual” for specic water heater 
installaon informaon, such as clearances, 
venng opons and parameter sengs. A copy is 
provided with each tankless water heater in the 
rack system.  
•  Proper installaon is the responsibility of the 
installer.  
•  When installaon is complete, leave this manual 
with the rack system or give the manual directly to 
the consumer. 
To The Consumer 
•  As when using any appliance generang heat, 
there are certain safety precauons you should 
follow. See the “Safety Precauons” secon in this 
manual for detailed safety precauons.  
•  It is recommended that a trained and qualied 
professional who has aended a Rinnai 
installaon training class complete your 
installaon.  
•  Keep this manual for future reference.  
 Welcome 
1 
If You Need Service 
Contact Rinnai Commercial Water Heang Services 
800-621-9419 
commercialservices@rinnai.us 
CONTENTS 
1 Welcome  2 
2 About  3 
3 Safety  3 
4 Conguraons  5 
5 Specicaons  8 
6 Installaon  30 
7 Venng  36 
8 Plumbing  38 
9 Gas Supply  42 
10 Power Supply  43 
11 Conguring TRW02ST and TRW03ST 
Rack Models 
46 
12 Connect Water Heaters  53 
13 Installaon Checklist  55 
14 Appendices  57 
 TRW Replacement Parts  57 
 TRW HE Series Replacement Parts  58 
 TRC Replacement Parts  59 
 TRS Replacement Parts  60 
15 Limited Warranty  62 
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