Honeywell PC8900A Manual page 20

CAUTION
Disconnect the power supply before connecting
wiring to prevent electrical shock or equipment
damage.
All wiring must comply with all applicable electrical codes,
ordinances and regulations.
1. Loosen the PC8900A terminal screws and insert one
wire beneath each terminal (1, 2, 3, 4). Four wires are
required at the PC8900A to assure operation. Note the
color of the wire that is attached to each terminal
number to later match the colors with the terminals on
the W8900A-C Remote Module. See Fig. 10 and 24 for
wiring technique and wiring diagram.
2. Tighten screw terminals securely.
3. Push the excess wire back into the hole. Plug the hole
with nonhardening caulk, putty or insulation to prevent
drafts from affecting PC8900A operation.
IMPORTANT
In replacement applications, more than four wires can be
available. In these applications, tape off the unused wires at
the PC8900A location and the W8900A-C location.
Mounting the C7189A Remote Sensor
(if needed)
Location Guidelines
• Choose a location where the C7189A is safe from
tampering.
• Locate the C7189A on an inside wall, about 5 ft (1.5m)
above the floor. The C7189A can also be mounted
vertically on a standard 2 x 4 in. (51 x 102 mm) outlet box.
• The wire distance between the C7189A and W8900A-C
should not exceed 200 ft.
• Install the C7189A in an area with good air circulation at
average temperature. Avoid the following locations
because they can introduce errors in sensor
measurements (see Fig. 25):
— Hot or cold areas caused by concealed pipes or ducts.
— Drafts from windows, doors, fireplaces or other heat/
cool sources.
— Convection or radiant heat from the sun or electrical
equipment.
— Unheated areas on the other side of the wall location.
— Dead air areas behind doors, furniture, curtains or in
corners and alcoves.
Mounting
1. Mark the mounting location on the wall for the C7189A
Remote Indoor Sensor or junction box.
NOTE: Order 202689A Coverplate when C7189A
cannot cover wall marks from old thermostat.
68-0173—3
2. Run cable from the W8900A-C Remote Module to a
hole at the selected wall location. Pull approximately
three inches of wire through the opening. Color-coded,
18-gauge thermostat wire is recommended.
1 NOTE WHICH COLOR WIRE IS ATTACHED TO EACH TERMINAL.
2
FOUR WIRES ARE REQUIRED FOR PROPER OPERATION.
IF FEWER THAN FOUR ARE AVAILABLE, ADDITIONAL WIRES
MUST BE RUN TO PC8900 LOCATION. IF MORE THAN FOUR
ARE AVAILABLE, TAPE OFF UNUSED WIRES.
3
IF SHIELDED CABLE IS REQUIRED, GROUND TO GND
TERMINAL ON W8900.
4 IN REPLACEMENT APPLICATIONS, PC8900 REPLACES OLD
THERMOSTATS, HUMIDISTATS, VENTILATION CONTROLS,
AND AIR CLEANER INDICATORS. BE SURE TO REMOVE
OLD DEVICES AND TAPE OFF UNUSED WIRES.
Fig. 24. Wiring diagram for PC8900A Control Panel to
W8900A-C Remote Module.
20
W8900
1
2
1
3
2
4
GND
4
3
1 2
1 2 3 4
M7519