Friedrich OES Series, Installation & Operation Manual

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10 11
920-138-02 (3-04) 920-138-02 (3-04)
THERMOSTAT WIRING
Attach thermostat wires to low-voltage terminal block on left side of control box in locations indicated in Figure 3.
Table 2 - Thermostat Wire Size
Transformer
V / VA
FLA
18 gauge
16 gauge
14 gauge
12 gauge 60
100
160
250
2.3 24/50
� CAUTION: Recheck wiring color code schedule to be certain
proper terminals are connected before applying power. Improper
wiring or installation may damage thermostat.
� WARNING: Failure to adhere to minimum wire sizes, maximum
overcurrent protection, disconnect, and grounding requirements
can cause personal injury, electric shock, or a fire hazard. All
wiring MUST comply with requirements of state and local codes
and ordinances and the national electric code.
�
WARNING: Electrical shock hazard. Turn OFF power to
heat pump before performing any maintenance or removing panels.
Failure to do so can result in personal injury and/or death.
Figure 10 – Thermostat Wiring
G R Y B W2 E C
Fan Compressor Auxiliary Common
Heat
24V Reversing Emergency
Valve Heat
G R Y B W2 E C or X
Unit Terminal
Thermostat Terminal
Wire Gauge
Maximum
distance in
Feet
�
DANGER: Electrical shock hazard. Turn OFF electric
power at the fuse box or service panel before making any
electrical connections and ensure a proper ground connection
is made before connecting line voltage. Failure to do so can
result in property damage, personal injury and/or death.
Grounding
�
CAUTION: The unit must be electrically wired and
grounded in accordance with all state and local codes,
national electric code, and NFPA 70. Unit and controls will
NOT operate unless properly grounded. A ground lug is
provided for ground connection. Use only approved copper
wire and connectors from unit to service panel. Ground lug
and line voltage connection terminals are located behind the
circuit breaker panel of the control box. Complete the ground
wire connection. After completing ground wire connection,
complete line voltage connections.
Low Voltage Wiring
All equipment is provided with 230/208 Volt, dual primary
voltage transformers. The factory setting is to wire them on
the 230V tap. If they need to be rewired to the 208V tap,
reconnect from the 230 to the 208V tap. The acceptable
operating voltage range for the 230 and 208V taps are shown
below. (The voltage should be measured at the field power
connection point in the unit and while the unit is operating at
full load (maximum amperage operating condition.))
NOTE: The operating voltage range for 230V is 253-216. For
the 208, it is 220-197.
High Voltage Wiring
1. Ensure that the power supply matches the correct
voltage, phase and ampacity for the selected model.
(See Tables 3 and 4)
2. The field wiring used must be sized to carry the units
maximum circuit ampacity.
3. In order to operate a nominal 230/208V unit at 208V
the transformer line tap should be changed from 240V
to 208V following the wiring label diagram in the unit.
4. Connect wires to the input side of the internal breaker
and install the ground wire on the ground lug.
LINE VOLTAGE ELECTRICAL WIRING
NOTE: B and E terminals are
used only on OHS models
Caution: Do not use thermostat wire with less than the recommended number of conductors.
!