Bryant SINGLE PACKAGED HEAT PUMP UNITS 657A - Manual (Page 18)

B. START UP AND MAKE ADJUSTMENTS
CAUTION: Complete the required procedures given in
the Pre-Start- Up section before starting the unit. Do not
jumper any safety devices when operating the unit. Do
not operate the compressor when the outdoor temperature
is below 40°F (unless accessory low-ambient kit is
installed). Do not rapid-cycle the compressor. Allow 5
minutes between “on” cycles to prevent compressor
damage.
C. CHECKING COOLING CONTROL OPERATION
Start and check the unit for proper cooling control operation as
follows:
1. Place room thermostat SYSTEM switch in OFF position.
Observe that blower motor starts when FAN switch is
placed in ON position and shuts down when FAN switch is
placed in AUTO position.
2. Place SYSTEM switch in COOL position and FAN switch
in AUTO position. Set cooling control below room tem-
perature. Observe that compressor, outdoor fan, and indoor
blower motors start. Observe that compressor and outdoor
fan shut down when control setting is satisfied and that
indoor blower shuts down after fan time delay expires.
3. When using an auto-changeover room thermostat, place
both SYSTEM and FAN switches in AUTO positions.
Observe that unit operates in heating mode when tempera-
ture control is set to “call for heating” (above room
temperature) and operates in cooling mode when tempera-
ture control is set to “call for cooling” (below room
temperature).
D. CHECKING HEATING CONTROL OPERATION
Start and check the unit for proper cooling control operation as
follows:
1. Place room thermostat SYSTEM switch in OFF position.
Observe that blower motor starts when FAN switch is
placed in ON position and shuts down when FAN switch is
placed in AUTO position.
2. Place SYSTEM switch in HEAT position and FAN switch
in AUTO position. Set cooling control above room tem-
perature. Observe that compressor, outdoor fan, and indoor
blower motors start. Observe that compressor and outdoor
fan shut down when control setting is satisfied and that
indoor blower shuts down after fan time delay expires.
3. When using an auto-changeover room thermostat, place
both SYSTEM and FAN switches in AUTO positions.
Observe that unit operates in heating mode when tempera-
ture control is set to “call for heating” (above room
temperature).
4. If system is equipped with supplemental or emergency heat
(resistance heaters), observe that when thermostat is placed
in EMERGENCY HEAT mode and temperature control is
set above room temperature that heaters and indoor blower
come on. Observe that heaters shut off when control setting
is satisfied and that the indoor blower shuts off after fan
time delay expires.
E. CHECKING AND ADJUSTING REFRIGERANT
CHARGE
The refrigerant system is fully charged with R-22 refrigerant,
tested, and factory-sealed.
NOTE: Adjustment of the refrigerant charge is not required
unless the unit is suspected of not having the proper R-22 charge.
A superheat charging chart is attached to the outside of the
compressor access panel. The chart includes the required suction
line temperature at given suction line pressures and outdoor
ambient temperatures (See Table 13A-H and Fig. 30).
An accurate superheat, thermocouple- or thermistor-type ther-
mometer, a sling psychrometer, and a gauge manifold are required
when using the superheat charging method for evaluating the unit
charge. Do not use mercury or small dial-type thermometers
because they are not adequate for this type of measurement.
Fig. 24—High-Voltage Connections
C99057
GROUND LUG
(IN SLPICE BOX)
BLU
YEL
BLK
GROUND
LEAD
SINGLE-PHASE
CONNECTIONS
TO DISCONNECT
PER NEC
3-PHASE
CONNECTIONS
LEGEND
NEC – National Electrical Code
Field Wiring
Splice Connections
NOTE: Use copper wire only.
L1
L3
L2
Fig. 25—Fan Blade Clearance
C95027
1/2 IN. MAX
FR OM FAN DECK
MOTOR SHAFT
MOTOR
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