Carrier ZW, ZN030-105, Z6, 48ZT, Z8075-105, 48ZG Smoke Control Modes, Field Control Thermostat Wiring

d. Secure shield wire to CCN screw terminal SHIELD on the COMM board.

IMPORTANT: A shorted CCN bus cable will prevent some routines from running and may prevent unit from starting. If abnormal conditions occur, unplug the connec- tor. If conditions return to normal, check CCN connector, and run new cable if necessary. A short in one section of the bus can cause problems with all system elements on the bus.

RJ14 PLUG WIRING — Units on the CCN can be monitored from the space at the sensor through the RJ14 connector, if desired. To wire the RJ14 connector into the CCN (Fig. 80):

IMPORTANT: The cable selected for the RJ14 connector wiring MUST be identical to the CCN communication bus wire used for the entire network.

1.Cut the CCN wire and strip ends of the red (+), white (ground), and black (–) conductors. (If another wire color scheme is used, strip ends of appropriate wires.)

2.Secure the red (+) wire to CCN screw terminal + on the COMM board.

3.Secure the white (ground) wire to CCN screw terminal C on the COMM board.

4.Secure the black (–) wire to CCN screw terminal – on the COMM board.

5.Secure shield wire to CCN screw terminal SHIELD on the COMM board.

6.Connect the other end of the communication bus cable to the CCN communication bus.

Smoke Control Modes — Rooftop units can be used for aid in building smoke control in the event of a building fire. The available functions include: Fire Shutdown, Pressuriza- tion, Evacuation, and Smoke Purge. These functions are enhanced when multiple rooftop units are used to zone a build- ing. See Table 21 and Fig. 78 and 79.

FIRE SHUTDOWN — Fire Shutdown mode terminates all unit operation (cooling, heating, supply fan, and power exhaust). This mode prevents recirculation of contaminated air back into the space. The mode will not allow admission into the space of unsuitable outside air. See Fig. 78 for wiring.

PRESSURIZATION — Pressurization mode is intended to keep smoke out of a zone. The factory-installed optional econ- omizer is required for this function. Pressurization is accom- plished by the following:

•opening the economizer (option)

•running the supply fan (optional inlet guide vanes open or optional VFD at normal duct static pressure set point)

•closing the power exhaust dampers (if installed as option or accessory)

•shutting off the power exhaust fans (if installed as option or accessory)

This allows the space to be overpressurized relative to adja- cent zones and prevents or slows entry of smoke into this space from adjacent zones. See Fig. 79 for wiring.

EVACUATION — Evacuation mode removes smoke or un- desirable air from interior spaces without reintroducing unsuit- able air. The factory-installed optional economizer with option/ accessory power exhaust is required for this function. Evacua- tion is accomplished by the following:

•turning the supply fan off

•opening the economizer (option required)

•running the exhaust fans (option or accessory required)

•opening the exhaust dampers. See Fig. 79 for wiring.

SMOKE PURGE — Smoke Purge mode removes smoke from the interior spaces and replaces it with fresh outside air. The factory-installed optional economizer with option/ accessory power exhaust are required for this function. Smoke purge is accomplished by the following:

•turning supply fan on

•opening the economizer (option required)

•running the exhaust fans (option or accessory required)

•opening the exhaust dampers See Fig. 79 for wiring.

SMOKE CONTROL INSTALLATION — Implementation of the various smoke control modes on these units requires the in- staller to modify the unit wiring to add contacts (via either manual switches or relays) that will selectively interrupt and override standard factory control sequences. See Table 21 and Fig. 78 and 79 for more information.

Table 21 — Smoke Control Modes

		MODE
FUNCTION	Fire	Pressur-	Evacuation*	Smoke
	Shutdown	ization		Purge*
Supply Fan	Off	On	Off	On
IGV/VFD†	—	Open/On	—	Open/On
Economizer	Closed	Open	Open	Open
Return Air	Open	Closed	Closed	Closed
Damper
Exhaust	Off	Off	On	On
Fans
Exhaust	Closed	Closed	Open	Open
Damper
LEGEND
IGV — Inlet Guide Vane
PIC — Product Integrated Control
VAV — Variable Air Volume
VFD — Variable Frequency Drive

*Power exhaust option required for this mode. †Applicable to VAV and PIC units with appropriate options.

FIELD SUPPLIED THERMOSTAT

R	RC	Y1	Y2	W1	W2	G
		Y1	Y2	W1	W2	G
R
1		6	5	4	3	2
			TB203

Fig. 67 — Field Control Thermostat Wiring

T55- SPTT56- SPT

T1 T2 TH C SN

	1	3	5	7	9	11	13	15
UNIT
TB202
	2	4	6	8	10	12	14	16

Fig. 68 — T55 or T56 Wiring

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