8. Seal around the openings where the vent piping passes
through the roof or side wall.
CAUTION; Vent piping must be insulated with 1/2"
Armaflex insulation if it will be subjected to freezing
temperatures such as routing through unheated ar-
eas or through an unused chimney.
This type installation requires two properly sized pipes. One
brings combustion air from a properly ventilated attic space and
a second pipe from the furnace vent connection (top right of
unit) exits to the outdoors.
COMBUSTION AIR INTAKE
Refer to Table 5 on page 12 for intake pipe sizing, allowable
length and elbow usage. Follow all notes, procedures and
required materials in the Two-Pipe Sealed Combustion section
(Method 1) when installing the combustion air pipe within the
unit and into the ventilated attic space.
COMBUSTION AIR TERMINATION
Refer to Figure 28 for required termination method and configura-
tion for the intake pipe. For attic termination, use two 90 elbows
with the open end in a downward position. Be sure to maintain 12"
clearance above any insulation, flooring or other material.
WARNING: Be sure to instruct the owner not to block
this intake pipe.
COMBUSTION AIR REQUIREMENTS
The ventilated attic space from which the combustion air is
taken must comply with the requirements shown on pages
14-16 in this instruction or in Section 5.3, Air for Combustion
and Ventilation of the National Fuel Gas Code, ANSI Z223.1
(current edition).
VENT PIPE
Refer to Table 7 on page 16 for vent pipe sizing, allowable length
and elbow usage. Follow all notes, installation procedures and
required materials in the One-Pipe System (Method 2), page
14 to install the vent pipe from the unit to the outdoors.
VENT TERMINATION
The vent pipe termination must be installed within the allowable
locations shown in Figure 24 and Section 7.8 in the National
Fuel Gas Code, ANSI Z223.1 (current edition). Follow all local
agency and utility requirements if more restrictive than those
shown. Vent termination must be as shown in Figures 25-27.
CONDENSATE PIPING
The condensate drain connection is packed in the furnace for field
installation. It consists of a formed hose with a 1/2" NPT male
connection. A 1/2" FM x 3/4" PVC slip coupling is provided.
This drain hose may be installed to allow left or right side
condensate drain connection. Refer to Figure 29. Cut the hose
to allow for proper fit for left or right exit.
To install the drain hose assembly, remove the 7/8" knockout in
the side panel. Remove the conduit nut from the 1/2" male
fitting. Push the male fitting through the hole and reinstall the
nut. The use of the 3/4" PVC coupling is optional.
Conversion of Horizontal Applications
Remove the condensate and its mounting bracket from the unit
side panel. Remove all drain hoses.
Reinstall the trap/bracket on the side panel which will be on the
bottom when teh unit is located horizontally. Use the original
mounting screws.
See Figure 30 for hose locations and Table 8 for hose cut
lengths. All hoses are identified as shown in Figure 30.
NOTE: Vent pipe must be sloped 1/4" per foot to allow conden-
sate to flow back to the furnace.
METHOD THREE: TWO
PIPE
SYSTEM
USING
COMBUSTION AIR FROM
A
VENTILATED
ATTIC
SPACE
In Canada, refer to CAN/CGA-B149.1 or .2 Installation Code
(latest edition - Venting Systems and Air Supply)
1 2 " M I N I M U M B E T W E E N
B O T T O M O F E L B O W A N D
A N Y M A T E R I A L
1 2 "
M I N I M U M
FIGURE 28 - ATTIC COMBUSTION AIR TERMINATION
In Canada, refer to CAN/CGA-B149.1 or .2 Installation Code
(latest edition - Venting Systems and Air Supply)
C O N D E N S A T E
T R A P T U B I N G
DOWNFLOW MODELS
FIGURE 29 - CONDENSATE DRAIN CONNECTION
LH DRAIN
RH DRAIN
UPFLOW MODELS
650.75-N4U
18
Unitary Products Group
