Rinnai V3237FFU - Manual (Page 31)

31
Rinnai Corporation V3237 Models
INSTALLER’S INSTALLATION CONSIDERATIONS
Venting
Air Intake and Exhaust Vent Pipe Length
To determine the maximum allowable air intake or exhaust vent pipe length reference Table 1 using
the following guidelines:
1. Determine the number of elbows in the intake air system. The corresponding number from the
table indicates the maximum length of intake air pipe.
2. Determine the number of elbows in the exhaust system. The corresponding number from the table
indicates the maximum length of the exhaust air pipe.
For high altitude installations contact Rinnai at 1-800-621-9419.
Condensate
Condensate formation can occur in Category III direct vent appliances. Space provisions must be
made to properly drain and dispose of the condensate. Refer to Figure 1.
•
Short horizontal vent runs (without a condensate drain) must slope to the vent termination 1/4” per
foot.
• Vertical terminations or long horizontal terminations must incorporate a condensate drain and trap
as close as possible to the appliance.
• The condensate drain trap must contain a minimum of 3” of water.
• Dispose of condensate per local codes.
Horizontal Venting Vertical Venting
FIGURE 1
Note: Some vent suppliers offer optional in-line condensate traps.
0 1 2 3 4 5 6
41 (1) 35 (2) 29 (3) 23 17 11 5
Table 1 Maximum Vent Length (feet) (Intake or Exhaust)
Number of 90°Elbows
(2) If the length is less than 16 ' then move dip switch no. 1 (SW1) to ON
(3) If the length is less than 10 ' then move dip switch no. 1 (SW1) to ON
Two 45° elbows are considered equivalent to one 90° elbow.
Include termination elbows when using this table.
(1) If the length is less than 22 ' then move dip switch no. 1 (SW1) to ON
Each 1 foot of semi rigid flex duct used in the air intake length is equivalent to one 90 degree elbow.