28
Rinnai Tankless Water Heater Installation and Operation Manual
Figure 22
Figure 23
Number of
90° elbows
Long (99-A)
(Default)
Short (99-b)
0
21-41 ft
(6.4-12.5 m)
0-20 ft
(0-6 m)
1
16-35 ft
(4.9-10.7 m)
0-15 ft
(0-4.6 m)
2
9-29 ft
(2.7-8.8 m)
0-9 ft
(0-2.8 m)
3
23 ft (7.0 m)
4
17 ft (5.2 m)
5
11 ft (3.4 m)
6
5 ft (1.5 m)
See "Parameter Settings Table" in section 4.10
for more information.
4.5.5 Maximum Vent Length
(indoor models only)
Horizontal Termination without using the
Condensate Collector
If the condensate collector is not used, the
supplied cap must remain installed to prevent
exhaust gases and condensate from entering
the building. The cap is supplied on the
appliance. When the condensate connector
is not used, slope the venting 1/4 in. per
foot away from appliance according to vent
manufacturer’s installation instructions.
WARNING
* The condensate collector must be used in
horizontal terminations if a vertical rise in the
vent system exceeds 5ft.
Maximum
Height*
Regions of cold climate will create more
condensate in the vent system. The condensate
collector should be used in cold climates.
If more than one elbow is used in the vertical
section the condensate collector must be used.
Slope the venting 1/4 in. per foot toward the
appliance according to the vent manufacturers
installation instructions. Dispose of condensate
per local codes.
Horizontal Termination using the Condensate
Collector
Condensation
3 in. (75 mm)
minimum
Figure 21
Table 11
4.5.6 Venting Installation
(indoor models only)
Install the venting termination according to the
diagrams and instructions below.
Default vent length is set for 21-41equivalent ft of
venting. If equivalent vent length is 20 ft or less,
parameter 10 must be changed to "b"
1. Determine the number of 90 degree elbows
in the vent system. (Two 45 degree elbows
count as one 90 degree elbow.)
2. Refer to the table to find the maximum vent
length based on the number of elbows.
