Carrier 58MVB Series Installation, Start-Up, And Operating Instructions Manual Download Page 44

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4. Use Fig. 54 or wiring schematic to determine proper setup

position of CF switches. (See Fig. 36 and 48.)

5. Replace main furnace door and blower access panel.

SETUP SWITCHES (SW1)

The furnace control has 8 setup switches that may be set to meet
the application requirements. Position these setup switches for the
appropriate requirement.

1. Remove main furnace door and blower access panel.

2. Locate setup switches on furnace control. (See Fig. 37.)

3. See Table 13 for setup switch description. (See Fig. 36 and

48.)

4. Replace main furnace door and blower access panel.

NOTE:

If a bypass humidifier is used, setup switch SW1-3 (Low

HEAT Rise Adjust) should be in ON position. This compensates
for the increased temperature in return air resulting from bypass.

NOTE:

If modulating dampers are used, blower motor automati-

cally compensates for modulating dampers.

Step 3—Prime Condensate Trap With Water

UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent unit
operation or performance satisfaction.
Condensate trap must be PRIMED or proper draining may not
occur. The condensate trap has 2 internal chambers which can
ONLY be primed by pouring water into the inducer drain side
of condensate trap.

1. Remove upper inducer housing drain connection cap. (See

Fig. 49.)

2. Connect field-supplied 1/2-in. ID tube to upper inducer

housing drain connection.

3. Insert field-supplied funnel into tube.

4. Pour 1 quart of water into funnel/tube. Water should run

through inducer housing, overfill condensate trap, and flow
into open field drain. (See Fig. 50.)

5. Remove funnel and tube from inducer housing and replace

drain connection cap and clamp.

Step 4—Purge Gas Lines

If not previously done, purge the lines after all connections have
been made and check for leaks.

FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in a fire, explosion,
personal injury, or death.
Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection of
leaks to check all connections.

Step 5—Sequence of Operation

UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent unit
operation.
Furnace control must be grounded for proper operation, or
control

will

lock

out.

Control

grounded

through

green/yellow wire routed to gas valve and burner box screw.

Using schematic diagram, follow sequence of operation through
different modes. (See Fig. 36.) Read and follow wiring diagram
carefully.

NOTE:

If a power interruption occurs during a call for heat

(W/W1 or W/W1-and-W2), the control will start a 90-second
blower-only ON period two seconds after power is restored, if the
thermostat is still calling for gas heating. The amber LED light will
flash code 12 during the 90-second period, after which the LED
will be ON continuous, as long as no faults are detected. After the
90-second period, the furnace will respond to the thermostat
normally.

The blower door must be installed for power to be conducted
through the blower door interlock switch ILK to the furnace
control CPU, transformer TRAN, inducer motor IDM, blower
motor BLWM, hot-surface igniter HSI, and gas valve GV.

SINGLE-STAGE THERMOSTAT AND TWO-STAGE
HEATING (ADAPTIVE MODE)

See Fig. 32 or 58 for thermostat connections

Table 13—Furnace Setup Switch Description

SETUP

SWITCH NO.

SWITCH

NAME

NORMAL

POSITION

DESCRIPTION

OF USE

SW1-1