Intellihot iN401, Operation & Installation Manual

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iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections 24
May 2019 - Revision 00
7.5 Combustion Air Requirements
When using the single exhaust gas outlet pipe or power vent
method, the following table outlines the required opening
sizes for the combustion and ventilation air coming into the
room and the required CFM requirements per water heater:
Required Combustion & Ventilation Air Opening Sizes (sq. in) Per Heater Per Boiler Room:
Model Input Air Type
Required
CFM
Air is drawn directly from outside into the
mechanical room
Air is drawn
from another
interior space
inside the
building
through two
openings*, direct
or vertical
through one
opening**
through two
horizontal ducts
iN401 399,999
Combustion Air 72 100
125
200 400
Ventilation Air 72 100 200 400
iN501 499,999
Combustion Air 90 125
125
250 500
Ventilation Air 90 125 250 500
*Where two openings are used, one must be within 12 inches of the floor and the other opening must be within 12 inches of the ceiling of the mechanical
room.
**Where one opening is required, it must be located within 12 inches of the ceiling.
SAFETY
INSTRUCTIONS
Do not operate the unit in an area that will draw in outside
air contaminated with high levels of dust, sawdust,
aerosols such as paint, or other airborne contaminants.
If necessary, purchase and install appropriate air screens
and follow a regular cleaning program to ensure an
adequate supply of clean, outside combustion air.
7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length
The iN401 and iN501 come factory installed with 4 inch
polypropylene (PP) venting. The following chart outlines the
maximum length of venting allowable for each model.
A vent system’s length is calculated by adding the length
of all straight runs used (both horizontal and vertical) and
then adding the equivalent lengths of each turn (90° or 45°
elbow) used in the system.
SAFETY
INSTRUCTIONS
A vent system’s length must not exceed the maximum
length outlined in the chart below.
Maximum Pipe Length in Feet
Number
of Units Venting
Type
Diameter, Model, and Length in Feet
4” Diameter 6” Diameter 8” Diameter
iN401 iN501 iN401 iN501 iN401 iN501
1
1 pipe - PV 250 180 250 250 250 250
2 pipe - DV 125 90 125 125 125 125
2
1 pipe - PV 82 50 250 250 250 250
2 pipe - DV 41 25 125 125 125 125
3
1 pipe - PV 40 250 176 250 250
2 pipe - DV 20 125 88 125 125
4
1 pipe - PV 250 250
2 pipe - DV 125 125
PV = Power Vent
DV = Direct Vent
Note:
Reduce the maximum equivalent length above by 5 feet per 90° elbow used and by 2 feet per 45° elbow used. Do not exceed the
above set limits.