Water Heater Installation Manual
28 Page
-Common-venng system-
The Indoor model can be vented together using the same exhaust and intake venting except 140H model.
• The 240HX3/340HX3/540HX3 models do not have Easy-Link or Multi-Unit capability.
• Up to 8 water heaters can be common-vented together.
• A non-return valve (100113130) must be used for each water heater that is part of the system.
• The water heaters must all be direct-vented.
• The common-venting system shall be in accordance with the National Fuel Gas Code,
ANSI Z223.1/NFPA 54 (Current Editions), local codes, and the venting manufacturer’s instructions.
• For common-venting pieces and components, the manufacturer recommends
Centrotherm's vent line.
Installaon
Installaon Manual
Intake
wall
Exhaust
Roof
Condensate drain port
Non-Return Valve
Exhaust
Intake
wall
Roof
Non-Return Valve
Condensate drain port
Allowable Indoor models for common-venting
240HX3, 340HX3, 540HX3, 240H, 340H, 540H, 540P, CT-199
NOTICE
For details on the installation of a
common-vent system, please refer
to "Common Venting Tankless Gas
Water Heaters." It is a manual
which is available on the water
heater manufacturer's website.
Only the models listed in the table above can be common-vented together. Other
models cannot be common-vented.
Failure to observe these warnings could lead to carbon monoxide poisoning or death.
WARNING
Exhaust
wall
Roof
Non-Return Valve
Condensate drain port
Intake
X3™ CARTRIDGE NOT SHOWN.