Carrier 48ZG, ZN030-105, ZW, Z6, 48ZT, Z8075-105 installation instructions Controls Installation

Table 19 — SGC Thermistor Designations

	PIN	FUNCTION AND LOCATION
THERMISTOR	CONNECTION		PART NO.
		Thermistors
	POINT
SAT1		Supply-Air Thermistor (SAT) — Inserted into supply section
	J8 – 1,2 (SGC)	underneath the gas heat section (factory-provided,
		field-installed)
SAT2		Supply-Air Thermistor (SAT) — Inserted into supply section
	J8 – 3,4 (SGC)	underneath the gas heat section (factory-provided,
		field-installed)	HH79NZ033
SAT3		Supply-Air Thermistor (SAT) — Inserted into supply section
	J8 – 5,6 (SGC)	underneath the gas heat section (factory-provided,
		field-installed)
LIMTTEMP	J8 – 15,16 (SGC)	Limit Switch Thermistor (LIMTTEMP) — Inserted next the
		lower limit switch (factory-installed)
SGC — Staged Gas Controller

Install Unit Accessories — For applications requiring accessories, the following packages are available:

All units:

•barometric relief

•space temperature sensor

•CO2 sensor

•space temperature sensor with CO2

•airflow switch

•filter switch

•smoke detector

All 48ZG,ZT,Z6 units:

•modulating power exhaust

•pressure operated unloaders

All 48ZN,ZW,Z8 units:

•modulating power exhaust

•VFD remote display

Refer to the individual accessory installation instructions in each accessory package for information on installing accessories.

CONTROLS INSTALLATION

Constant Volume (CV) Units — The 48ZG,ZT,Z6 units may be used in applications with additional control features, options, or accessories. Refer to the appropriate accessory installation instructions for more information on installing that accessory. Control options and accessories available for CV units are:

•thermostats

•enthalpy sensor

•enthalpy switch

•relative humidity sensor

•CEM (controls expansion module)

•Navigator™ hand-held display

CONTROL WIRING — The unit can be controlled with a Carrier-approved accessory electro-mechanical or electronic thermostat that has two stages of cooling, two stages of heating control, and an output for fan control. The thermostat may also include time of day scheduling or use scheduling routines built into the ComfortLink™ controls.

Install the thermostat according to the installation instruc- tions shipped with the accessory thermostat. Locate thermostat assembly on a solid interior wall to sense average temperature.

Route thermostat cable or equivalent leads of colored wire from subbase terminals through conduit into the low voltage connections in the main control box. For thermostat TB203 connections, see Fig. 67.

NOTE: For wire runs up to 50 ft, use no. 18 AWG (American Wire Gage) 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 at the thermostat and will require a junction box and splice at the thermostat.

Variable Air Volume (VAV) Units — The 48ZN, ZW, Z8 units may be used in applications with additional con- trol features, options, or accessories. Refer to the appropriate accessory installation instructions for more information on in- stalling that accessory. Refer to the Controls and Troubleshoot- ing manual for more information concerning installation and configuration of options and accessories. Control options and accessories available for VAV units are:

•enthalpy sensor

•enthalpy switch

•relative humidity sensor

•CEM (controls expansion module)

•Navigator hand-held display

•VFD remote display

VAV CONTROL WIRING — The recommended types of control wiring are shown below:

MANUFACTURER	PART NO.
	Regular Wiring	Plenum Wiring
Alpha	1895	—
American	A21451	A48301
Belden	8205	884421
Columbia	D6451	—
Manhattan	M13402	M64430
Quabik	6130	—

SENSORS — Sensors should be wired using single twisted pairs of 20 AWG (American Wire Gage) conductor cable rated for the application, except for the T-56 accessory sensor which requires 3-conductor cable.

NOTE: Humidity and CO2 sensors must be powered from isolated 24-v power supplies.

HUMIDITY CONTROL AND HOT WATER AND STEAM VALVES — These devices require 20 AWG twisted pair conductor cables rated for the application for the 4 to 20 mA signal.

SPACE TEMPERATURE SENSOR (T-55) — The space tem- perature sensor (P/N 33ZCT55SPT) is shipped standard with every unit, and is located in the main control box. Space tem- perature sensor wires are to be connected to terminals in the unit main control box.

CAUTION

Jumper MUST be in place between pins 1 and 3, 3 and 4 or inaccurate readings could result.

To connect the space temperature sensor, see Fig. 68.

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