Trane 2TWR1 Installer's Manual page 5

3. FRC_DFT = Forced Defrost (Short TEST_COMMON to
this pin for two (2) seconds to initiate a forced defrost.
Remove the short after defrost initiates.)
DEFROST CONTROL CHECKOUT
Normal operation requires:
a. LED on board flashing 1 time/second.
b. 24V AC between R & B
c. 24V AC between Y & B with unit operating
d. Defrost initiation when FRC_DFT pin is shorted to
TEST_COMMON pin.
If a defrost control problem is suspected, refer to the service
information in control box.
▲
WARNING
!
Do NOT connect 24 VAC to T1 (ODS-A) terminal. ODS-A
thermistor WILL BE BLOWN.
H. COMPRESSOR START UP
After all electrical wiring is complete, SET THE THERMO-
STAT SYSTEM SWITCH IN THE OFF POSITION SO
COMPRESSOR WILL NOT RUN, and apply power by closing
the system main disconnect switch. This will activate the
compressor sump heat (where used). Do not change the
Thermostat System Switch until power has been applied for
one (1) hour. Following this procedure will prevent potential
compressor overload trip at the initial start-up.
Notes:
1. Be sure power supply agrees with equipment nameplate.
2. Power wiring and grounding of equipment must comply with local codes.
3. Low voltage wiring to be No. 18 AWG minimum conductor.
4. ODT-B must be set lower than ODT-A.
5. If outdoor thermostats (ODT) are not used, connect W1 to W2 and W3.
6. N/A to programmable thermostat.
18-BC51D2-3
TYPICAL FIELD HOOK-UP DIAGRAMS
Installer's Guide
I. OPERATIONAL AND CHECKOUT
PROCEDURES
Final phases of this installation are the unit Operational and
Checkout Procedures which are found in this instruction on
page 8. To obtain proper performance, all units must be
operated and charge adjustments made in accordance with
procedures found in the Service Facts.
J. ELECTRIC HEATERS
Electric heaters, if used, are to be installed in the air han-
dling device according to the instructions accompanying the
air handler and the heaters.
K. START CONTROL
Some models have quick start components which are factory
installed. For models that do not have factory installed start
components, provisions are made for a field installed start kit
accessory. When adding an accessory, follow the instructions
provided with the kit.
L. OUTDOOR THERMOSTAT
An outdoor thermostat TAYSTAT250B may be field installed.
For data, see wiring diagram attached to unit and instruction
sheet packaged with outdoor thermostat.
M. SEACOAST SALT SHIELD
Units installed within one mile of salt water including
seacoasts and inland waterways, require the addition of
BAYSEAC001 (Seacoast Kit) at the time of installation.
IMPORTANT:
See Limited Warranty information in Use and Care Manual.
LEGEND
FACTORY WIRING
FIELD WIRING
5