Bryant Legacy 549J 12 Series, Руководство по установке

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Shorting the jumpers for a period of 5 to 20 seconds bypasses
the remaining continuous run period and places the unit in a
Forced Defrost mode. If the controlling DFT is closed when
this mode is initiated, the unit will complete a normal defrost
period that will terminate when the controlling DFT opens or
the 10 minute defrost cycle limit is reached. If the controlling
DFT is open when this mode is initiated, the Defrost cycle will
run for 30 seconds. Both modes end at the end of the Defrost
cycle.
Fig. 37 — DIP Switch Settings - Defrost Board
UNIT WITHOUT THRU-BASE CONNECTION KIT
Pass the thermostat control wires through the bushing on the
unit end panel. Route the wire through the snap-in wire tie and
up to the web bushing near the control box. Route the wire
through the bushing and into the bottom left side of the control
box after removing one of the two knockouts in the corner of
the box. Using a connector at the control box to protect the
wire as it passes into the control box. Pull the wires over to the
terminal strip at the upper left corner of the Central Terminal
Board (CTB). Use the connector at the control box and the
wire tie to ensure that the thermostat wire is tight and will not
be damaged by contact with the condenser coil. See Fig. 38.
NOTE: If thru-the-bottom connections accessory is used, refer to
the accessory installation instructions for information on routing
power and control wiring.
Fig. 38 — Thermostat Wire Routing
HEAT ANTICIPATOR SETTINGS
Set heat anticipator settings at 0.14 amp for the first stage and
0.14 amp for second-stage heating, when available.
ELECTRIC HEATERS
The 549J units may be equipped with field-installed accessory
electric heaters. The heaters are modular in design, with heater
frames holding open coil resistance wires strung through ce -
ramic insulators, line-break limit switches and a control con -
tactor. One or two heater modules may be used in a unit.
Heater modules are installed in the compartment below the in -
door (supply) fan outlet. Access is through the indoor access
panel. Heater modules slide into the compartment on tracks
along the bottom of the heater opening. See Fig. 39.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Not all available heater modules and single point boxes
may be used in every unit. Use only those heater modules
that are UL listed for use in a specific size unit. Refer to the
label on the unit cabinet for the list of approved heaters and
single point boxes.