4
Connect the Power Transformer —
An individual,
field-supplied, 24 vac power transformer is required for each
fan coil controller. Transformers must be UL Class 2 rated.
Standard applications require a 24 VAC transformer, rated at 40
VA minimum. All transformer secondaries are required to be
grounded. Use only stranded copper conductors for all wiring
to the fan coil controller. Wiring connections must be made in
accordance with NEC (National Electrical Code) and local
codes. Ground one side of the transformer secondary at the
transformer location. Connect the grounded side of the trans-
former to J1-2. Connect the live side of the transformer second-
ary to J1-1. Connect an 18-gage, green ground wire from ter-
minal J1-3 to the metal chassis of the unit.
The power supply is 24 vac ± 10% at 40 va (50/60 Hz).
For fan coil controllers, the power requirement sizing
allows for accessory water valves and for the fan contactor.
Water valves are limited to 10 va on both two-position and
modulating hot water. The fan contactor is limited to 3 va
(holding) for each fan output.
NOTE: If a water valve contactor exceeds these limits, or
external contactors are required for electric heat, then it is
recommended a 60 va transformer be used. The maximum
rating for any single output is 20 va.
NOTE: Do not run sensor or communication wiring in the
same conduit with line-voltage wiring.
NOTE: An accessory conduit box (part no. 33ZCCONBOX)
is available for conduit wiring connections to the fan coil
controller.
Perform the following steps to connect the power
transformer:
1. Install the field-supplied transformer in an electrical
enclosure that conforms to NEC and local codes.
2. Connect 24 vac from the transformer as shown in the
applicable wiring diagram (Fig. 4-10). Be sure to
observe polarity when connecting the transformer
power. The grounded terminal must be connected to
the transformer ground terminal as shown.
Fan Coil Controller Inputs and Outputs —
The
fan coil controller inputs and outputs are shown in Fig. 11-13.
Fig. 2 — Fan Coil Controller
→
J4
RH
GND
IAQ
+10V
SPEED
GND
CONDSW
GND
+24V
SPT
GND
SAT
T56
GND
CNGOVR
RMT/FS
J3
J1
SR
VC
24V
AC
+
G
-
Part Number: 33ZCFANCOL
S/N:
Bus#:
Element#:
Unit#:
J5
VL
V/DX1
COM
VL
V/DX2
HEA
T1
24V
AC
HEA
T2
ZONE Controller
®
C
US
1
6
3
1
+
G
-
J2A
CCN
LEN
J2B
+
G
-
1
1
1
3
3
2
15
16
FAN AC
FAN ON
LOW
MED
HIGH
J6
1
5
LED1
LED2
24VAC
OAD ENA
J7
1
2
3 IN.
ALLOW 12-IN. FOR SERVICE
FAN COIL
UNIT
FAN COIL
CONTROLLER
Fig. 3 — Service Clearance for Fan Coil Zone
Controller Mounting
1001
