Rheem RTGH-C95DVLN Installation Instructions Manual page 13

Common Venting for Direct-Vent Water Heater
Only commercial tankless water heaters (RTGH-
C95DVLN and RTGH-CM95DVLN) with common vent
gas chip are allowed to utilize the InnoFlue® common
venting system. The common vent gas chip is shipped
with these applicable models. These commercial
tankless models without the common vent gas chip,
or any other tankless models are prohibited to utilize
Rheem approved common venting system.
DANGER:
Failure to properly vent the water heater to the outdoors
as outlined in this Venting section will result in death or
serious personal injury. To avoid the risk of fire, explosion,
or asphyxiation from carbon monoxide, NEVER operate the
water heater unless it is properly vented and has adequate
air supply for proper operation as outlined in this Venting
section. This water heater must have air supply connected
and terminated to the outdoors.
WARNING:
Refer to page 16 for required clearances to combustible
materials. Improper clearances can cause explosion or fire
resulting in death, personal injury, and/or product damage.
CAUTIONS:
• Check to make sure flue gases DO NOT recirculate into the
air intake terminal when using direct venting. If the water
heater is having service issues, flue recirculation may be a
contributing factor.
• Even when the minimum vent terminal separation
distances are followed, recirculation may still occur
depending upon the location outside the building, the
distance from other buildings, proximity to corners,
weather conditions, wind patterns, and snow depth.
• Periodically check to make sure that flue recirculation
is not occurring. Signs of flue gas recirculation include
frosted or frozen intake terminals and condensate in the
intake terminal and venting system.
• Correction to flue recirculation may involve angling the
intake away from the exhaust terminal and increasing the
distance between them. Check to be sure the intake and
exhaust terminals are not obstructed, especially during
periods of below-freezing weather.
Venting Requirements
The installation of venting must comply with national
codes, local codes, and the vent manufacturer's
instructions.
The vent exhaust and air intake must terminate outside
as described in these instructions. DO NOT terminate
exhaust pipe or air intake pipe in a chimney. It must be
vented separately from all other appliances.
NOTICE:
The unit with common vent can be vented using only the
following approved vent pipe material.
Use only 8 inch diameter InnoFlue® common vent
INSTALLATION INSTRUCTIONS
pipe. Use 3 or 4 inch diameter InnoFlue® vent pipe to
connect a tankless water heater with the common vent
trunk. Refer to local codes for restrictions on the use
of InnoFlue® PP pipe and fittings. All exhaust venting
materials for product installed in Canada must meet
ULC-S636.
The use of cellular core PVC (ASTM F891), cellular
core CPVC, or Radel® (polyphenolsulfone) in non-
metallic venting systems is prohibited and that
covering non-metallic vent pipe and fittings with
thermal insulation is prohibited.
Common venting system shall be in accordance with
the National Fuel Gas Code, ANSI Z223.1/NFPA 54
and/or the CSA B149.1, Natural Gas and Propane
installation Code (Current Editions), local codes, and
the manufacturer's instructions. This Common vent is
permitted for commercial installation only.
Acceptable materials:
InnoFlue® PP
The fittings, other than the VENT TERMINAL,
should be equivalent to the following:
InnoFlue® PP
DO NOT USE any flexible vent.
Recommended Vent Lengths
Before starting the vent installation, careful planning
should be given to the routing and termination of the
vent pipes. The length of the vent pipes (air intake and
exhaust) should be kept to a minimum. Also, see pages
18-20 and 29-31 for vent terminal placement. Refer to
the maximum and minimum vent length charts for the
pipe sizes that can be used and the total equivalent
length of pipe that can be used. DO NOT exceed
equivalent length of pipe in maximum vent length chart.
Maximum Vent Length (air intake and exhaust) each:
Number of
water heaters
2
3
4
5
6
7
8
9
10
Equivalent Vent Length:
87 Degree
Elbow
45 Degree
Elbow
8" Common
Vent
100' (30 m)
100' (30 m)
100' (30 m)
100' (30 m)
82' (25 m)
55' (17 m)
43' (13 m)
N/A
N/A
8" Common
Vent
5.0' (1.5 m)
2.5' (0.8 m)
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