Bryant Legacy 547K 14, Installation Instructions Manual

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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.
ELECTRIC HEATERS
The 547K*14 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 ceramic insulators, line-break limit switches and a
control contactor.
Heater modules are installed in the compartment below the in -
door (supply) fan outlet. Access is through the electric heat
access panel. See Fig. 36-38.
Not all available heater modules 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.
Refer to the Small Roof Top Units Accessory Electric Heater
and Single Point Box installation instructions for further
details.
Fig. 36 — Access Panel Location
Fig. 37 — Component Location
Fig. 38 — Heater Module Installation
Control Box
Non-Fused
Disconnect*
* Factory-Installed Option.
Convenience
Outlet*
Single
Point Box
Center
Post
Control Wire
Terminal Block Heater
(Cover Removed)
Heater Mounting
Bracket
Manual Reset
Limit Switch
Vane Axial
Indoor Fan System
Heater Module