Service And Maintenance Procedures; Introduction; Electrical Controls And Wiring - Carrier 58SU0A Installation, Start-Up, Operating And Service And Maintenance Instructions

Table 11 – Gas Valve Outlet Pressure for Gas Heat Values at
Altitude − 60,000
(Tabulated Data Based on 60,000 BTUH Input for 0-ft (0m) to
2000-ft (610-m) above sea level)
AVG. GAS
HEAT VALUE
ALTITUDE
AT ALTITUDE
RANGE
ft (m) (Btu/cu ft)
900
0 925
(0) 950
975
to 1000
1025
2000 1050
(610) 1075
1100
Table 12 – Gas Valve Outlet Pressure for Gas Heat Values at
Altitude − 80,000
(Tabulated Data Based on 80,000 BTUH Input, for 0-ft (0-m) to
2000-ft (610-m) above sea level)
AVG. GAS
HEAT VALUE
ALTITUDE
AT ALTITUDE
RANGE
ft (m) (Btu/cu ft)
900
0 925
(0) 950
975
to 1000
1025
2000 1050
(610) 1075
1100
SERVICE AND MAINTENANCE
PROCEDURES
Untrained personnel can perform basic maintenance functions
such as cleaning and replacing air filters. All other operations
must be performed by trained service personnel. A qualified
service person should inspect the furnace once a year.
WARNING
!
FIRE, INJURY, OR DEATH HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
The ability to properly perform maintenance on this
equipment requires certain knowledge, mechanical skills,
tools, and equipment. If you do not possess these, do not
attempt to perform any maintenance on this equipment
other than those procedures recommended in the User's
Manual.
SPECIFIC GRAVITY OF
NATURAL GAS
0.58 0.60 0.62 0.64
Gas Valve Outlet Pressure
(in. W.C.)
2.8 2.9 3.0 3.1
2.6 2.7 2.8 2.9
2.5 2.6 2.7 2.8
2.4 2.5 2.5 2.6
2.3 2.3 2.4 2.5
2.1 2.2 2.3 2.4
2.0 2.1 2.2 2.3
1.9 2.0 2.1 2.2
1.9 1.9 2.0 2.1
SPECIFIC GRAVITY OF
NATURAL GAS
0.58 0.60 0.62 0.64
Gas Valve Outlet Pressure
(in. W.C.)
2.7 2.8 2.9 2.9
2.5 2.6 2.7 2.8
2.4 2.5 2.6 2.6
2.3 2.3 2.4 2.5
2.2 2.2 2.3 2.4
2.0 2.1 2.2 2.3
1.9 2.0 2.1 2.2
1.9 1.9 2.0 2.1
1.8 1.8 1.9 2.0
WARNING
!
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag.
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
CAUTION
!
ELECTRICAL OPERATION HAZARD
Failure to follow this caution may result in improper
furnace operation or failure of furnace.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous
operation.

INTRODUCTION

GENERAL
These instructions are written as if the furnace is installed in an
upflow application. An upflow furnace application is where the
blower is located below the combustion and controls section of
the furnace, and conditioned air is discharged upward. Since this
furnace can be installed in any of the 4 positions shown in Fig. 4,
you must revise your orientation to component location
accordingly.

ELECTRICAL CONTROLS AND WIRING

WARNING
!
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
There may be more than one electrical supply to the
furnace. Check accessories and cooling unit for additional
electrical supplies that must be shut off during furnace
servicing. Lock out and tag switch with a suitable warning
label.
The electrical ground and polarity for 115−v wiring must be
properly maintained. Refer to Fig. 24 for field wiring information
and to Fig. 38 for furnace wiring information.
NOTE: If the polarity is not correct, the STATUS LED on the
control will flash rapidly RED and prevent the furnace from
heating. The control system also requires an earth ground for
proper operation of the control and flame−sensing electrode.
The 24−v circuit contains an automotive−type, 3−amp. fuse
located on the control. (See Fig. 38) Any shorts of the 24−v
wiring during installation, service, or maintenance will cause this
fuse to blow. If fuse replacement is required, use ONLY a 3−amp.
fuse. The control LED will display a three flash AMBER code
when fuse needs to be replaced.
Proper instrumentation is required to service electrical controls.
The control in this furnace is equipped with a multi−colored
Status Code LED (Light−Emitting Diode) to aid in installation,
servicing, and troubleshooting. The furnace control LED is either
ON continuously, rapid flashing, or displaying a flash code in one
of three colors (Red, Green, or Amber).
30
There may be more than one