Start-Up Procedures - Carrier 58TUA Installation, Start-Up, And Operating Instructions Manual

(1.) The thermostat closes the R-G circuit for low heat and
starts the furnace blower motor BLWM on heat pump
low-heat speed (identical to low-cooling speed). Clos-
ing the R-Y/Y2 circuit to the furnace provides blower
motor BLWM heat pump high-heat speed.
NOTE: The furnace control CPU controls blower motor BLWM
speed by sensing only G (for heat pump low-heat speed) and Y2
(for heat pump high-heat speed).
(2.) The EAC terminals EAC-1 and EAC-2 are energized
with 115v when the blower motor BLWM is operating
on either heating speed.
(3.) When the thermostat is satisfied, the furnace blower
motor BLWM continues operating on the heating
speed for an additional 90 sec.
(4.) Opening only the R-Y/Y2 circuit reduces the blower
motor BLWM speed to heat pump low-heat speed.
6. Defrost
a. When the furnace control R to W/W1-and-Y/Y2 circuits
are closed, the furnace control CPU continues blower
motor BLWM operation at the heat pump heating speed
until the end of the prepurge period, then shuts off until the
end of the HSI ignitor-on period (22 sec).
b. When installed with a heat pump, the furnace control CPU
automatically holds the blower off time to 22 sec during the
HSI ignitor on period. After 17 sec of the HSI ignitor-on
period, a trial for ignition sequence occurs as described
above for gas heating. After flame is proved and without a
blower on delay, the blower motor BLWM will operate on
high-gas-heat speed during defrost. For both single-speed
and 2-speed heat pumps, defrost mode is in high-gas heat
only.
c. When furnace control R-W/W1 circuit is opened, the
furnace control CPU begins the normal inducer post purge
period and the blower motor BLWM remains on for the
blower off delay period. If the R-G circuit remains closed,
the blower motor BLWM reverts to continuous operation.

START-UP PROCEDURES

1. Component test—The furnace features a component test
system to help diagnose a system problem in the case of a
component failure. To initiate the component test procedure,
ensure that there are no thermostat inputs to the control and all
time delays have expired. Short the TWIN/TEST terminal to
ground or Com for 1 to 4 sec. (See Fig. 10.)
NOTE: The component test feature will not operate if the control
is receiving any thermostat signals or until all time delays have
expired.
The component test sequence is as follows:
a. The furnace control checks itself, operates the inducer
motor on low speed for 7 sec and on high speed for 7 sec,
then stops.
b. The hot surface ignitor is energized for 15 sec, then
de-energized.
c. The blower motor operates on low-gas-heat/heat pump
low-heat/low-cool/continuous fan speed for 7 sec, then
stops.
d. The blower motor operates on high-gas heat for 7 sec, then
stops.
e. The blower motor operates on heat pump high-heat/high-
cool speed for 7 sec, then stops.
The gas valve and humidifier terminal HUM are not energized
for safety reasons.
EAC - ELECTRONIC
AIR CLEANER
(115-VAC 1 AMP MAX)
7 8
4 5
1 2
Fig. 10—Control Center
BLOWER-
OFF
DELAY
LOW
HEAT
(ADAPTIVE
ALOGRITHM)
ONLY
HIGH
HEAT
Fig. 11—Setup Switches on Control Center
(Factory Settings)
NOTE: The EAC terminals are energized when the blower is
energized.
2. After all connections have been made, purge gas lines and
check for leaks.
Never purge a line into a combustion chamber. Never use
matches, candles, flame, or other sources of ignition for the
purpose of checking leakage. Use a soap-and-water solution
to check for leakage. A failure to follow this warning can
cause a fire, explosion, personal injury, or death.
3. To operate furnace, follow procedures on operating instruc-
tions label attached to furnace.
12
3-AMP
9
FUSE
6
3
LED -
DIAGNOSTIC
LIGHT
10 11 12
7 8 9
4 5 6
TWIN / TEST
1 2 3
TERMINAL
MASTER SLAVE
1
HUM -
HUMIDIFIER
(24-VAC 0.5
AMP MAX)
24-VOLT
THERMOSTAT
TERMINALS
FURNACE AND
BLOWER OFF DELAY
SETUP SWITCHES
ON OFF
4
3
2
1
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