Trane NO Series, Installation Instructions Manual

11

Pre-Electrical Checklist

√

  Verify the voltage, frequency, and phase of the supply source 

match the specifications on the unit rating plate.

√

 Verify that the service provided by the utility is sufficient to 

handle the additional load imposed by this equipment. See 

Table 2 (page 11)

 and 

Table 9 (page 25)

 (or the unit 

rating label) for proper high voltage wiring requirements.

√

 Verify factory wiring is in accordance with the unit wiring 

diagram. See 

Figure 12 (page 24)

. Make sure the 

connections didn’t loosen during shipping or installation.

Grounding

 WARNING:

The unit cabinet must have an uninterrupted or 

unbroken electrical ground to minimize personal 

injury if an electrical fault should occur. Do not use 

gas piping as an electrical ground!

This unit must be electrically grounded in accordance with 

local codes or, in the absence of local codes, with the National 

Electrical Code (ANSI/NFPA 70) or the CSA C22.1 Electrical 

Code. Grounding of the unit is accomplished by using the 

grounding lug provided in the control box.

Line Voltage

• The line voltage to the unit should be supplied from a 

dedicated branch circuit containing the correct fuse or circuit 

breaker for the unit.

• 

An electrical disconnect must be located within sight 

of and readily accessible to the unit

. This switch shall be 

capable of electrically de-energizing the outdoor unit. See 

unit data label for proper incoming field wiring. Any other 

wiring methods must be acceptable to authority having 

jurisdiction.

•  Use only copper wire for the line voltage power supply to 

this unit as shown in 

Table 2

. Use proper code agency listed 

conduit and a conduit connector for connecting the supply 

wires to the unit. Use of rain tight conduit is recommended.

•  Provide power supply for the unit in accordance with the 

unit wiring diagram and the unit rating plate.

•  Overcurrent protection must be provided at the branch circuit 

distribution panel and sized as shown on the unit rating 

label and according to applicable local codes. See 

Table 9

(or the unit rating plate) for minimum circuit ampacity and 

maximum overcurrent protection limits.

•  A wiring diagram is located on the inside cover of the control 

access panel of the outdoor unit. The installer should become 

familiar with the wiring diagram before making any electrical 

connections to the outdoor unit. See 

Figure 12

.

• Units are shipped from the factory wired for 230 volt 

transformer operation.

• Connect the line-voltage leads to the terminals on the 

contactor inside the control compartment.

Thermostat / Low Voltage Connections

•  This unit is designed to operate from a 24 VAC Class II 

control circuit. A single stage cooling / single stage heating 

thermostat should be used with this unit. A 2-stage cooling / 

2-stage heating thermostat is recommended for economizer 

operation. See 

Figure 6 (page 11)

 for typical thermostat 

connection.

• The control circuit wiring must comply with the current 

provisions of the NEC (ANSI/NFPA 70) and with applicable 

local codes having jurisdiction. Thermostat connections 

should be made in accordance with the instructions supplied 

with the thermostat and the indoor equipment.

•  The low voltage wires must be properly connected. Route 

24V control wires through the sealing grommet near the 

power entrance.

•  Several thermostat options are available depending on the 

accessories installed with the unit. Select a thermostat that 

operates in conjunction with the installed accessories.

•  The thermostat should be mounted about 5 feet above the 

floor on an inside wall. DO NOT install the thermostat on 

an outside wall or any other location where its operation 

may be adversely affected by radiant heat from fireplaces, 

sunlight, or lighting fixtures, and convective heat from warm 

air registers or electrical appliances. Refer to the thermostat 

manufacturer’s instruction sheet for detailed mounting 

information.

Checking Heat Anticipator Settings

•  Add the current draw of the system heating components.

OR

• Measure the current flow on the thermostat 

R

-

W

 circuit 

after the circulating blower motor has started. Set the heat 

anticipator according to the thermostat manufacturer’s 

instructions for heat anticipator settings.

COPPER WIRE SIZE — AWG

(1% VOLTAGE DROP)

SUPPLY WIRE LENGTH-FEET

SUPPLY CIRCUIT

AMPACITY

200

150

100

50

6

8

10

14

15

4

6

8

12

20

4

6

8

10

25

4

4

6

10

30

3

4

6

8

35

3

4

6

8

40

2

3

4

6

45

2

3

4

6

50

2

3

4

6

55

1

2

3

4

60

NOTE:

 Wire Size based on N.E.C. for 60° type copper conductors.

Table 2. Copper Wire Size

Figure 6. Typical Thermostat Connection 

(Field Supplied) for 1-Stage Cool / 1-Stage Heat

C

Y1

R

G

W1

R

C

Y

G

W1

Y2

TERMINAL BLOCK

FURNACE

BOARD

Optional, Refer to

Thermostat Instructions

INDOOR THERMOSTAT

SUB-BASE (TYPICAL)

A1