Rinnai Tankless Water Heater Installation and Operation Manual
51
Schedule 40 PVC/CPVC Common Vent Guidelines
Header
Vent
Figure 50: PVC/CPVC Common Vent
Installation
DO NOT
•
Do not mix vent pipe, fittings or joining
methods from different vent manufactur
-
ers.
•
DO NOT attempt to repair damaged
vent. Damaged vent components must
be replaced.
•
DO NOT use short radius elbows in the
common vent system.
Acceptable
Acceptable
Not
Acceptable
90° Elbows,
Long Sweep
90° Elbows,
Short Sweep
90° Elbows,
Close Turn
Table 23
WARNING
PVC solvents (primer and glue) can be extremely flammable. Vapors may
cause a flash fire or explosion resulting in property damage, personal injury
or death.
•
Keep solvents away from heat, sparks, flames and all other sources of ignition.
•
Do not solder, cut or weld until all vapors have dissipated.
•
PVC solvents are heavier than air causing them to settle at low points of the system.
•
Before Using PVC solvent
–
Disconnect power to the water heater.
–
Remove the front cover of the water heater.
–
Ensure areas around the water heater and PVC venting are all well ventilated.
–
Allow all vapors to dissipate before applying power to the system or introducing any other
source of ignition.
When installing PVC/CPVC Common Vent, follow these guidelines:
•
Avoid sharp bends or tees in the vent system.
These vent components create additional re
-
strictions that could reduce performance of the
water heaters.
•
PVC combustion air and exhaust should termi
-
nate with elbow or tee pointing down. This will
stop unwanted moisture from entering the vent
system.
•
Fire rated penetrations shall be firestopped.
Contact your vent supplier or local firestop man
-
ufacturer for appropriate firestop methods.
•
Examine all vent components for damage prior
to installation.
•
PVC/CPVC vent systems must be free to
expand and contract. Refer to the vent manu
-
facturer’s installation instructions for appropriate
support methods.
•
PVC/CPVC venting must include unrestricted
vent movement through walls, ceilings, and roof
penetrations.
•
Use only PVC/CPVC primer and cement ap
-
proved for use by the vent manufacturer.
•
Refer to vent manufacturer’s installation instruc
-
tions for proper joint assembly procedures and
products.
•
PVC/CPVC common venting should include a
condensate drain and trap between the header
and vent length. Condensate trap must include
a loop that can hold 6 in. (15 cm) of water.
Refer to the Rinnai Common Vent Installation
manual for more information.
