Bryant 548F - Manual (Page 13)

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B. Field Control Wiring
Install a Bryant-approved accessory thermostat assembly
according to installation instructions included with the
accessory. Locate thermostat assembly on a solid wall in the
conditioned space to sense average temperature in accor-
dance with thermostat installation instructions.
NOTE: If using Bryant electronic thermostat, set thermostat
configuration for “non-heat pump operation.” The use of the
O terminal is not required to energize the reversing valve in
this family of products.
Route thermostat cable or equivalent single leads of colored
wire from subbase terminals to low-voltage connections on
unit (shown in Fig. 7) as described in Steps 1 through 3
below.
NOTE: For wire runs up to 50 ft, use no. 18 AWG (American
Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft,
use no. 16 AWG insulated wire (35 C minimum). For over
75 ft, use no. 14 AWG insulated wire (35 C minimum). All
wire larger than no. 18 AWG cannot be directly connected to
the thermostat and will require a junction box and splice at
the thermostat.
1. Connect thermostat wires to screw terminals of low
voltage connection board.
2. Pass the control wires through the hole provided in
the corner post.
3. Feed wire through the raceway built into the corner
post to the 24-v barrier located on the left side of the
control box. See Fig. 8. The raceway provides the UL-
required clearance between the high- and low-voltage
wiring.
C. Defrost Board
The defrost board timer is set for a 30 minute defrost cycle
from the factory. To adjust to a 50 or 90 minute cycle, remove
the wire connected to the 30 minute quick connect on the
defrost board. See Fig. 9. Connect lead to the 50 or 90 minute
quick connect on the defrost board, depending on the appli-
cation.
D. Heat Anticipator Settings
Set first-stage heat anticipator setting at 0.8 and set second-
stage heat anticipator setting at 0.3.
VI. STEP 6 — ADJUST FACTORY-INSTALLED OPTIONS
A. Disconnect Switch
The optional disconnect switch is non-fused. The switch has
the capability of being locked in place for safety purposes.
The disconnect switch is only available for limited applica-
tions. See electrical data tables on pages 8-12 for disconnect
switch usage.
B. Optional Durablade Economizer
The optional economizer hood assembly is packaged and
shipped in the filter section. Damper blades and control
boards are installed at the factory and the economizer is
shipped in the vertical discharge position.
NOTE: Horizontal discharge block-off plate is shipped with
the air hood package. If unit is to be used for vertical dis-
charge application, discard this plate.
LEGEND
Fig. 7 — Low-Voltage Connections With or
Without Economizer or Two-Position Damper
AHA — Adjustable Heat Anticipator
CC — Cooling Compensator
Field Wiring
Factory Wiring
*Used with economizer.
†Used with 2-stage electric
heater.
†
Fig. 8 — Field Control Wiring Raceway
Fig. 9 — Defrost Board