Honeywell W180 User Manual page 19

3. Determine if power is available at the W180A Con-
troller location. The W180A Controller is powered by a
separate dedicated 24 Vac transformer. When suitable power
is not available where the W180A Controller will be lo-
cated, add the appropriate power connections. A maximum
of three S321A Touchpads can be powered through the
W180A Controller.
CAUTION
To prevent damage to the W180A Controller, do
not connect either side of the 24 Vac transformer
secondary to earth ground.
4. Determine the equipment locations. For single fam-
ily residential buildings, a separate drawing for the HVAC
system might not be available. If a separate HVAC drawing
is not available, draw the duct and damper layout on the
architectural plans. If any of the temperature control zones
of a particular forced air HVAC system are controlled by
motorized dampers, all zones on that particular HVAC
system must be controlled by dampers. Observe the follow-
ing when determining equipment locations:
— W180A Controller: Locate the W180A Controller in
a central location that will minimize the length of
wire runs.
— Touchpad: Mount the Touchpads in any room conve-
nient for the user. However, mounting in bathrooms
and other high humidity areas is not advised. The
power supply provided with the W180A Controller
supports a maximum of three Touchpads. If more
Touchpads are required, additional power supplies
must be provided. Mount the Touchpad 5 ft 4 in.
[1.6m] above the floor or as specified by the cus-
tomer for easy viewing.
— Dampers and valves (observe the following):
• Locate dampers where they can be easily ac-
cessed after installation.
• Locate the dampers close to the HVAC unit.
• If the HVAC equipment supplies more than one
zone, because all zones served by the equipment
have at least one damper or valve.
• To assure proper operation, properly size dampers
for the air duct. If the damper is forced into an
undersized air duct, the excess pressure can jam
the damper blades and cause improper operation.
• Do not install dampers in heating systems where
spray or atomizing type humidifiers are installed
in the furnace plenum or air supply duct. Exces-
sive lime or mineral deposits accumulate on damper
blades and cause improper operation. For
humidification, use evaporative or return air type
humidifiers.
— Indoor temperature sensors. (One temperature sensor
is required for each control zone; three types of
indoor temperature sensors can be used with the
system: C7130, C7180, and T7660.) Locate indoor
temperature sensors:
• On an interior wall.
• Near the return air flow.
• Out of the sun.
• Away from supply registers.
• Away from hot or cold sources.
• About 60 inches above the floor.
• Free from obstructions.
— Outdoor temperature sensor. An outdoor temperature
sensor is required whenever alternate fuel equipment
is going to be controlled or if outdoor temperature
lockout is desired. A typical location would be under
the roof overhang on the least sunny side of the
building. Locate the outdoor temperature sensor:
• Out of the sun (consider the seasonal position of
the sun).
• Away from exhausts that may affect the tempera-
ture reading.
— Humidity sensor:
• Exposed to freely circulating air.
• Duct mount indoors, or outdoors protected from
rain, snow, and direct sunlight.
• In areas with 500 ft/min minimum air flow.
— Alternate fuel equipment. For mounting location re-
quirements, see the literature for the equipment.
5. Determine the wiring. Fig. 14 and Table 9 detail the
various wires that are allowed. Figs. 15 through 20 show
typical device wiring.
NOTES:
a. All wiring must conform to all local codes and
ordinances.
b. Keep large inductive loads such as motors and fans
off the power circuits feeding any portion of the
system.
c. Motorized damper wiring should not be run through
air ducts or plenums. If such routing is necessary,
only type FPLP (fire) wire may be used.
d. Verify the number of conductors required to operate
each HVAC unit.
e. Leave at least 24 inches of wire at the device end
and 24 inches at the W180A Controller end.
f. Label all wires at both ends and record wire data on
the job drawings.
g. Use twisted pair cables for wiring to the temperature
sensors and S321A Touchpads.
h. Run wiring so that it will not be damaged during
other installations.
i. Prewire all devices as home runs back to the W180A
Controller.
j. Do not wire a mechanical thermostat in parallel with
the system controls.
k. When the HVAC unit is more than 100 cable feet
from the W180A Controller, calculate the voltage
drop on the cable. Determine the worst-case power
consumption, loop resistance of the cable, and cable
19
W180 ZONE CONTROL SYSTEM
68-0139