SAFETY CONSIDERATIONS
Installing and servicing heating equipment can be hazardous due to gas and electrical components. Only trained and qualified personnel should
install, repair, or service heating equipment.
Untrained personnel can perform basic maintenance functions such as cleaning and replacing air filters. All other operations must be performed
by trained service personnel. When working on heating equipment, observe precautions in the literature, on tags, and on labels attached to or
shipped with the unit and other safety precautions that may apply.
Follow all safety codes. In the United States, follow all safety codes including the National Fuel Gas Code (NFGC) NFPA No. 54-1992/ANSI
Z223.1-1992. In Canada, refer to the current edition of the National Standard of Canada CAN/CGA-B149.1- and .2-M91 Natural Gas and Propane
Installation Codes (NSCNGPIC). Wear safety glasses and work gloves. Have fire extinguisher available during start-up and adjustment procedures
and service calls.
Recognize safety information. This is the safety-alert symbol
. When you see this symbol on the unit and in instructions or manuals, be alert
to the potential for personal injury.
Understand the signal word DANGER, WARNING, or CAUTION. These words are used with the safety-alert symbol. DANGER identifies the
most serious hazards which will result in severe personal injury or death. WARNING signifies a hazard that could result in personal injury or death.
CAUTION is used to identify unsafe practices which would result in minor personal injury or product and property damage. NOTE is used to
highlight suggestions that will result in enhanced installation, reliability, or operation.
These instructions cover minimum requirements and conform to existing national standards and safety codes. In some instances, these instructions
exceed certain local codes and ordinances, especially those that may not have kept up with changing residential construction practices. We require
these instructions as a minimum for a safe installation.
INTRODUCTION
The model GB3AAV Series C Furnaces are available in sizes 50,000 through 135,000 Btuh input capacities.
The design of the downflow/horizontal gas-fired furnace is A.G.A./C.G.A. certified for natural and propane gas and for installation on
noncombustible flooring. The furnace may be installed on combustible flooring when installed with the accessory downflow subbase. This furnace
is for installation in alcoves, attics, crawlspaces, basements, closets, or utility rooms. The design of this furnace line is not A.G.A./C.G.A. certified
for installation in mobile homes, recreation vehicles, or outdoors.
Before installing the furnace, refer to the current edition of the NFGC. Canadian installations must be installed in accordance NSCNGPIC and all
authorities having jurisdiction. For further information, the NFGC is available from National Fire Protection Association Inc. Batterymarch Park,
Quincy, MA 02269, American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209, or from Literature Distribution.
Table 1—Clearances From Combustible Materials (In.)
UNIT SIZE
050 AND 070
095-135
DOWNFLOW (In Alcove or Closet)
Sides
Single-Wall Vent
1
0
Type B-1 Double-Wall Vent
0
0
Back
0
0
Top
1
1
Front
Single-Wall Vent
6†
6†
Type B-1 Double-Wall Vent
3†
3†
Vent
Single-Wall Vent
6
6
Type B-1 Double-Wall Vent
1
1
HORIZONTAL (Attic, Alcove, or Crawlspace)
Sides *
1
0
Back
0
0
Top
Single-Wall Vent
1
1
Type B-1 Double-Wall Vent
1
1
Front‡
Single-Wall Vent
6†
6†
Type B-1 Double-Wall Vent
3†
3†
Vent
Single-Wall Vent
6
6
Type B-1 Double-Wall Vent
1
1
HORIZONTAL (In Closet)
Sides *
1
1
Back
0
0
Top
Single-Wall Vent
2
2
Type B-1 Double-Wall Vent
2
2
Front
Single-Wall Vent
6
6
Type B-1 Double-Wall Vent
3
3
Vent
Single-Wall Vent
6
6
Type B-1 Double-Wall Vent
1
1
* Indicates supply or return sides when furnace is in the horizontal position.
† Clearance shown is for outlet end. The inlet end must maintain 6-in. minimum clearance from the vent to combustible materials when using single-wall vent.
‡ Minimum 18-in. front clearance required for alcove.
NOTES:
1. Provide 30-in. front clearance for servicing. An open door in front of the furnace can meet this requirement.
2. A minimum clearance of 3 in. must be provided in front of the furnace for combustion air and proper operation.
3. Line contact is permitted as shown in Fig. 7.
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