Electrical
ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION
Electrostatic discharge can affect elec- tronic components. Take precautions to neutralize electrostatic charge by touching your hand and tools to metal prior to handling the control.
The unit is equipped with a field make−up box on the left hand side of the cabinet. The make−up box may be moved to the right side of the furnace to facilitate installation. If the
make−up box is moved to the right side, clip the wire ties that bundle the wires together. The excess wire must be pulled into the blower compartment. Secure the excess
wire to the existing harness to protect it from damage.
INTERIOR MAKE−UP BOX INSTALLATION
Left side
BOX
FIGURE 28
INTERIOR MAKE−UP BOX INSTALLATION
Right Side
BOX
FIGURE 29
Refer to figure 33 for unit field wiring. See figures 30 and 31 for icomfort Touch® thermostat wiring in communicating applications. Table 11 shows DIP switch and on−board link settings for non−communicating thermostat applications. Typical wiring schematic is shown in figure 32.
1 − The power supply wiring must meet Class I restric- tions. Protected by either a fuse or circuit breaker, se- lect circuit protection and wire size according to unit nameplate.
NOTE − Unit nameplate states maximum current draw. Maximum over−current protection allowed is shown in table 10.
TABLE 10
SL280UH Model | Maximum Over−Current | |
Protection (Amps) | ||
| ||
|
| |
070V36A, 09036B | 15 | |
|
| |
090V48B, 090V60C, 110V60C, | 20 | |
135V60D | ||
| ||
|
|
2 − Holes are on both sides of the furnace cabinet to facili- tate wiring.
3 − Install a separate (properly sized) disconnect switch near the furnace so that power can be turned off for servicing.
4 − Before connecting the thermostat or the power wiring, check to make sure the wires will be long enough for servicing at a later date. Remove the blower access panel to check the length of the wire.
5 − Complete the wiring connections to the equipment. Use the provided unit wiring diagram and the field wir- ing diagrams shown in table 11 and figure 33. Use 18−gauge wire or larger that is suitable for Class II ra- ting for thermostat connections.
6 − Electrically ground the unit according to local codes or, in the absence of local codes, according to the current National Electric Code (ANSI/NFPA No. 70). A green ground wire is provided in the field make−up box.
NOTE − The SL280UHV furnace contains electronic components that are polarity sensitive. Make sure that the furnace is wired correctly and is properly grounded.
7 − One line voltageade terminal is provided on the furnace integrated control. Any electronic air cleaner or other accessory rated up to one amp can be connected to this terminal with the neutral leg of the cir- cuit being connected to the one of the provided neutral terminals. See figure 34 for control configuration. This terminal is energized when the indoor blower is operat- ing.
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