Bryant 373LAV Service And Maintenance Procedures Manual

SAFETY CONSIDERATIONS
NOTE: Read the entire instruction manual before performing any
service or maintenance.
This symbol indicates a change since the last issue.
These procedures are for size 45,000 through 155,000 Btuh input
units.
Index
SAFETY CONSIDERATIONS..................................................1-2
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
PROCEDURE ...........................................................................2
CARE AND MAINTENANCE................................................2-11
Air Filter Arrangement..........................................................2-3
Blower Motor and Wheel......................................................3-4
Cleaning Heat Exchanger......................................................4-5
Electrical Controls and Wiring .............................................5-6
Troubleshooting ...................................................................6-11
Unit Wiring Diagram................................................................8
Service Label ............................................................................9
Troubleshooting Guide ......................................................10-11
SAFETY CONSIDERATIONS
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified person-
nel 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.
54-1996/ANSI Z223.1-1996 and the Installation Standards, Warm
Air Heating and Air Conditioning Systems (NFPA 90B)
ANSI/NFPA 90B. In Canada, refer to the current edition of the
National Standard of Canada CAN/CGA-B149.1- and .2-M95
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 furnace and in instructions or
manuals, be alert to the potential for personal injury.
Understand the signal words DANGER, WARNING, and CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies a hazard which
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 which will result in enhanced installation, reliability,
or operation.
service and
maintenance procedures
GAS-FIRED
INDUCED-COMBUSTION FURNACES
Page
.
-1-
Cancels: SP04-44
Fig. 1-Model 373LAV Horizontal
®
ama
A PP R O VED
R
REGISTERED QUALITY SYSTEM
A94085
Fig. 3-Model 383KAV
Upflow
373LAV
383KAV
Series G
SP04-53
9-98
A94087
A94086
Fig. 2-Model 373LAV
Downflow