Carrier 50TFQ008-012 specifications Adjust Factory-InstalledOptions

FIELD CONTROL WIRING — Install a Carrier-approved accessory thermostat assembly according to the installation instructions included with the accessory. Locate the thermostat assembly on a solid wall in the conditioned space to sense aver- age temperature in accordance with the thermostat installation instructions.

NOTE: If using a Carrier electronic thermostat, set the thermo- stat configuration for “non-heat pump operation.” This family of products does not require an O terminal to energize the reversing valve.

Route the thermostat cable or equivalent single leads of colored wire from the subbase terminals to the low-voltage connections on the unit (shown in Fig. 8A and 8B) as described in Steps 1 through 4 below.

NOTE: For wire runs up to 50 ft, use no. 18 AWG (American Wire Gage) insulated wire (35 C minimum). For 51 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.If the unit is mounted on the roof curb and the accessory thru-the-curb service plate connection is used, route wire through the connection plate.

2.Pass control wires through the hole provided on the unit (see connection D in Connection Sizes table in Fig. 6).

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. 9. The raceway provides the UL required clear- ance between the high-voltage and low-voltage wiring.

4.Connect the thermostat wires to the screw terminals of the low-voltage connector (see Fig. 8A and 8B).

NOTE: If the unit is mounted on a roof curb and electrical power will be run up “thru-the-bottom,” use accessory kit number CRBTMPWR002A01. This kit, available from your local distributor, ensures a watertight seal. Refer to the acces- sory installation instructions for information on power wiring. Refer to Fig. 6 for drilling holes in basepan.

DEFROST BOARD — The defrost board timer cycle is set to 30 minutes. To change the cycle time, turn off power to the unit and install lockout tag. Remove the wire from defrost board connected to the 30 minute quick-connect. See Fig. 10. Connect the wire to the 50 or 90 minute quick-connects on the defrost board, depending on the desired defrost time.

HEAT ANTICIPATOR SETTINGS — For units with electric heat, set heat anticipator settings as shown in Table 4.

Step 6 — Adjust Factory-Installed Options

DISCONNECT SWITCH — The optional disconnect switch is non-fused. The switch can be locked in place for safety purposes.

	CONTROL	THERMOSTAT CONTROL
CONNECTION		CONNECTION
	BOARD		BOARD
R	24 VAC	R	R
G	RMTOCC	Y1	Y1
	CMPSAFE	Y2	Y2
Y2	FSD	W1	W1
W1	SFS	W2	W2
	NOT USED	G	G
C	C	C	C
X	X	X

Fig. 8B — Low Voltage Connections (Units with PremierLink™ Controls)

DISCONNECT

BOARD

COOL STAGE 1	Y1/W2
FAN	G
HEAT STAGE 1	W/W1
COOL STAGE 2	Y/Y2
HEAT STAGE 2	O/W2
24 VAC HOT	R
24 VAC COM	C
N/A
OUTDOOR AIR	S1
SENSOR	S2

R

G

Y1

Y2

W1

W2

C

IPD/X

WIRE CONNECTIONS TO LOW-VOLTAGE SECTION (CONNECTION BOARD)

DISCONNECT SWITCH (OPTIONAL)

RACEWAY

COMPRESSOR

NO. 2

CONVENIENCE OUTLET

THERMOSTAT DIPSWITCH SETTINGS

ON

OFF

A B C D

LEGEND

Field Wiring

NOTE: Underlined letter indicates active thermostat output when configured for A/C operation.

Fig. 8A — Low-Voltage Connections With or Without Economizer or Two-Position Damper

HOLE IN

END

PANEL

COMPRESSOR NO. 1

Fig. 9 — Typical Field Control Wiring Raceway

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