Transformer Information; Heater Staging; Manufactured Housing; Transformer Connections - Carrier fb4cnf024 Installation Instructions Manual

THERMOSTAT
[27b
[]
FAN COIL
(CONTROL)
HEAT PUMP
(CONTROL)
R
G
c
W2 E
W 3 S
C
R
C
W2
o
Y
Fig. 13 - Wiring Layout Heat Pump Unit
(Cooling and 2-Stage Heat with
1 Outdoor Thermostat)
FAN COIL
(CONTROL)
R
G
_ BR_
C
_ WH] W2 _
BLU
w3
v!o
ODT
ODT
THERMOSTAT HEAT PUMP
(CONTROL)
R
C
W2
O
Y
A94061
EMERGENCY HEAT RELAY
A94062
Fig. 14 - Wiring Layout Heat Pump Unit (Cooling and
2-Stage Heat with 2 Outdoor Thermostats)
[]
[]
[]
[]
THERMOSTAT FAN COIL
(CONTROL)
HEAT PUMP
(CONTROL)
R
C
,[ w2
O
v
A0a088
Fig. 15 - Wiring Layout Heat Pump Unit
(Cooling and 2-Stage Heat for Manufactured Housing)
Refer to outdoor unit wiring instructions for any additional wiring
procedure recommendations.
Transformer Information
Transformer is factory-wired for 230v operation. For 208v
applications, disconnect the black wire from the 230v terminal on
transformer and connect it to the 208v terminal. (See Fig. 16.)
RED
YEL
Fig. 16 - Transformer Connections
Heater Staging
A05182
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or
property damage.
If W2, W3, and E on any 3 stage heater (18, 20, 24, or
30kW) are individually connected as with outdoor
thermostats or any other situation, emergency heat relay must
be used. This relay is in kit Part No. KHOT0201SEC and is
normally used with kit Part No. KHAOT0301FST for 2
outdoor thermostat systems.
The controls are factory circuited for single-stage operation. For
2-stage operation, use outdoor thermostat kit Part No.
KHAOT0301FST, and for 3-stage use both kits Part No.
KHAOT0201SEC and KHAOT0301FST.
When 2 stages are desired, cut W3 at the W2 wire nut, strip and
reconnect per the thermostat kit instruction. (See Fig. 14.) When 3
stages are desired, cut the W2 wire nut off and discard. Strip W2,
W3, and E and reconnect per thermostat kit instructions. (See Fig.
14.)
NOTE: When 3 stages are used or anytime the E terminal is not
tied to W2, the emergency heat relay, part of outdoor kit Part No.
KHAOT0201SEC nmst be used.
C. Manufactured Housing
In manufactured housing applications, the ('ode of Federal
Regulations, Title 24, Chapter XX, Part 3280.714 requires that
supplemental electric heat be locked out at outdoor temperatures
above 40°F (4°C), except for a heat pump defrost cycle. Refer to
Fig. 15 for typical low voltage wiring with outdoor thermostat.