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capacities of compressor high and low speeds. To select recom-
mended airflow, refer to Table 3 and the 58UHV,58UXV Instal-
lation Instructions. These settings are made on the furnace airflow
selector board by moving the appropriate color-coded jumper
wires. The ORANGE jumper wire should be set to the HP—EFFY
position for heat pump best efficiency or HP—CMFT for heat
pump enhanced comfort. The YELLOW COOL SIZE jumper is
used to select airflow to match the needed tons of cooling. The
BLUE CFM/TON jumper wire is used to select slight adjustments
to airflow of 400, 350, or 315 CFM per ton. (See Table 3.)
AIRFLOW SELECTION FOR 58MVP FURNACES
The 58MVP Condensing Variable-Speed Furnaces provide high-
and low-speed blower operation to match the capacities of com-
pressor at high and low speeds. To select recommended airflow,
refer to Table 4 and the 58MVP Installation Instructions. The
58MVP utilizes a control center that allows the installing techni-
cian to select proper airflows. For adjustments to the manual
switches labeled A/C and CF and recommended switch positions,
refer to Table 4. High-speed airflow is determined by the position
of the A/C switches, and low-speed airflow is determined by the
position of the CF switches. This furnace has a built-in, non-
adjustable 90 sec off delay for cooling mode blower operation.
AIRFLOW SELECTION FOR FK4C OR 40FKA FAN COILS
The FK4C or 40FKA provides high- and low-speed blower
operation to match the capacities of compressor at high and low
speeds. To select recommended airflow, refer to Table 5 and the
FK4C or 40FKA Installation Instructions. The FK4C or 40FKA
utilizes an EASY SELECT control board that allows the installing
technician to select proper airflows. The ORANGE SYSTEM
TYPE
jumper
wire
should
be
set
to
HP—EFF
or
HP—COMFORT. The BLUE AC/HP SIZE JUMPER is used to
select airflow to match the outdoor unit nominal size in tons of
cooling. The BLACK AC/HP CFM ADJUST jumper is used to
make slight adjustments to the selected airflow tonnage. (See
Table 5.) This fan coil has an adjustable blower off delay factory
set at 90 sec for high- and low-speed blower operation.
Step 11—Start-Up
To prevent compressor damage or personal injury, observe
the following:
• Do not overcharge system with refrigerant.
• Do not operate unit in a vacuum or at negative pressure.
• Do not disable low-pressure switch.
In scroll compressor applications:
• Dome temperatures may be hot.
To prevent personal injury wear safety glasses, protective
clothing, and gloves when handling refrigerant and observe
the following:
• Back seating service valves are not equipped with Schrader
valves. Fully back seat (counter clockwise) valve stem before
removing gage port cap.
Do not vent refrigerant to atmosphere. Recover during system
repair or final unit disposal.
Follow these steps to properly start up the system:
1. The outdoor unit is equipped with a crankcase heater which
operates at temperatures less than 75°F. If outdoor tempera-
ture is less than 75°F, energize crankcase heater 24 hr before
starting unit. To energize heater only, set indoor thermostat to
the OFF position and close power disconnect to the unit.
2. Fully back seat (open) liquid and vapor tube service valves.
Table 2—Wiring Diagram Reference
INDOOR PRODUCT
THERMOSTAT
CONTROLS
DIAGRAM LETTER
IN FIG. 8
Standard Fan Coil
Carrier Programmable (Model 2S)
Latent Capacity
A
Carrier Non-Programmable (Model 2S)
Latent Capacity
B
Carrier Thermidistat™ Control (Model RH) Humidifier and Outdoor Sensor
C
Other Brand Models
Latent Capacity
D
FK4C Fan Coil
Carrier Programmable (Model 2S)
—
E
Carrier Non-Programmable (Model 2S)
—
F
Carrier Thermidistat™ Control (Model RH) Humidifier and Outdoor Sensor
G
Other Brand Models
—
H
Single-Stage Furnace
Carrier Programmable (Model 2S)
Latent Capacity
J
Carrier Non-Programmable (Model 2S)
Latent Capacity
K
Carrier Thermidistat™ Control (Model RH) Humidifier and Outdoor Sensor
L
Carrier Dual Fuel Thermostat (Model DF)
Outdoor Sensor
M
Other Brand Models
Latent Capacity
N
Two-Stage Furnace with PSC Blower Motor
Carrier Programmable (Model 2S)
Latent Capacity
P
Carrier Non-Programmable (Model 2S)
Latent Capacity
Q
Carrier Dual Fuel Thermostat (Model DF)
Outdoor Sensor
V
Carrier Thermidistat™ Control (Model RH) Humidifier and Outdoor Sensor
R
Other Brand Models
Latent Capacity
S
Two-Stage Furnace with ICM Blower Motor
Carrier Programmable (Model 2S)
—
T
Carrier Non-Programmable (Model 2S)
—
U
Carrier Dual Fuel Thermostat (Model DF)
Outdoor Sensor
V
Other Brand Models
—
W
Variable-Speed 80% Non-Condensing Furnace
Carrier Thermidistat™ Control (Model RH) Humidifier and Outdoor Sensor
X
Carrier Dual Fuel Thermostat (Model DF)
Outdoor Sensor
Y
Variable-Speed Condensing Furnace
Carrier Thermidistat™ Control (Model RH) Humidifier and Outdoor Sensor
Z
5