Form I-XE/CRGB/RPB, Page 12
Top
Bottom
12
(305mm)
2 (51mm)
3/8
(10mm)
Vent Cap
Vent Opening
Furnace Top
Vent Cap
Extension
Control Compartment
Access Panel
FIGURE 9B - Vent
Cap Installation
FIGURE 9A - Vent Cap
Extension, P/N 20524
8B. Venting - Gravity-Vented, Outdoor Model
Series CRGB
The appropriate size of gravity vent cap is supplied with the furnace.
The
gravity vent cap requires field installation.
WARNING: This gravity-vented furnace should be
located on a roof or slab with at least 30-foot (9M)
radius between the center of the vent cap and
obstructions such as walls, parapets or cupolas. See
Hazard Levels, page 2.
8A. Gravity-Vented Models XE/HXE (cont'd)
Venting Requirements - Indoor Models (cont'd)
(b)
Use double-wall, Type B vent pipe which is recommended for the
reduction or elimination of condensate problems. Where extreme condi-
tions are present and condensate is anticipated, install a trap for collect-
ing condensate.
8.
The vent connection may be made into a suitable permanent chimney
or into a gas vent. The effective area of the vent con-nector, gas vent, or
chimney when connected to a single appliance shall not be less than the
area of the appliance drafthood outlet or in accordance with approved
venting methods. The effective area of the gas vent or chimney when
connected to more than one appliance shall not be less than the area of
the largest vent connector plus 50% of the areas of additional vent
connectors or in accordance with approved venting methods.
Minimum permissible height of the vertical vent is five feet (1.5M)
providing no horizontal vent pipe connector is used. If a horizontal
vent connector is necessary, consult
TABLES 1 or 2
or the National
Fuel Gas Code or the Canadian Installation Code for Gas Burning
Appliances, for the maximum permissible length of a horizontal pipe
run (vent connector) for a given vertical height of gas vent.
The gas vent or chimney should extend at least three feet (.9M) above
the highest point where it passes through a roof of a building and at
least two feet (.6M) higher than any portion of a building or obstruc-
tion within a horizontal distance of ten feet (3M). A suitable weather
cap should be installed on the end of the vent pipe to prevent rain or
snow from entering the open end.
9.
If the heater is installed in a space served by a large exhaust fan, be sure
that the exhaust fan does not affect the operation of the heater or the
satisfactory venting of its products of combustion.
If a negative pressure exists, as evidenced by a downdraft, a factory-
designed mechanical motor driven venter (Option CA) should be in-
stalled. In severe negative pressure conditions, makeup air equipment
may be necessary.
Optional Power Venting (Option CA)
To install a gravity-vented furnace in an area where horizontal venting is
required or where negative building pressure inhibits gravity venting, in-
stall an optional power venter (Option CA). Use only a power venter
provided by the furnace manufacturer and carefully follow the instruc-
tions included in the optional venter package. Use the venter adapter
supplied to connect the power venter to the heater.
Do not install the
power venter without the venter adapter.
With an Option CA power venter installed, the furnace may be vented
either horizontally or vertically. Do not exceed the maximum vent lengths
shown in the table below. Minimum vent length is 5 ft (1.5M).
Vent Cap Installation Instructions:
IMPORTANT REQUIREMENT
For proper operation of the gravity vent cap, position the
holes so that the solid side panel of the cap will face the
control compartment access panel side of the furnace. See
FIGURE 9B.
1) Furnaces that do not require a Vent Cap Extension
(H)CRGB Sizes 75- 300,
align holes and attach the vent cap to the
furnace flue collar with sheetmetal screws.
(See Important Require-
ment above.)
2) Furnaces that require a Vent Cap Extension (packed inside
the vent cap) - See FIGURES 9A and 9B
(H)CRGB Sizes 350 and 400
require a 12" extension to raise the
vent cap above the top of the furnace.
a) Remove the extension from the inside of the cap.
b) Attach the extension to the furnace flue collar --
1) With 3/8" centerline clearance holes at the bottom, wrap
extension
around
flue collar on the top of the furnace.
2) Align holes in the extension with holes in the flue collar.
3) Secure with #10 1/2" sheetmetal screws.
c) Attach the vent cap to
the extension --
1) Position vent cap
into
top of extension.
(See Important
Requirement
above)
2) Align holes and push
cap into extension.
3) Secure with 1/2"
sheetmetal screws.
Optional 4-foot (1.2M) Stack Extension for
Outdoor, Gravity Vent Models (Option ZZ)
Outdoor, gravity-vented furnaces that are factory-built with Option
ZZ are designed to release flue gases four feet (1.2M) above the top
of the furnace. A field-provided 4-ft (1.2M) vent extension must be
installed between the top of the furnace and the bottom of the vent
cap. (See
FIGURE 9C
). Furnaces with Option ZZ (factory-installed
restrictor plus field-provided 4-ft stack) may be installed adjacent to
fresh air inlet(s) when local code requires that release of flue gases be
above an adjacent fresh air inlet that is not part of the furnace.
75, 100, 125, 150 175
200
225
250
300
350
400
ft
100
75
50
35
30
15
M
30
23
15
11
9
4.6
ft
100** 100** 100
92
M
30**
30**
30
4"
6"
Maximum* Vent Length (ft or M) for Furnace with Optional
Power Venter (Option CA)
Vent Pipe
Diameter
*
Reduce the vent pipe lengths as follows for each item: 45° Elbow - 7ft
(2.1M); 90° Elbow - 15ft (4.6M); Reznor
®
or Breidert Vent Cap - 10ft (3M).
**
If the venter outlet is 4", connect a taper-type "enlarger" to the vent
outlet when installing 6" vent pipe.
Model
Size
Vent Cap
Size
Extension Required
75, 100
6"
125, 175
8"
No
225, 250, 300
10"
350, 400
12"
Yes (packed inside cap)
(H)CRGB
