Carrier 48KHA - Manual (Page 14)

Table 6—Model 48KHA,KLA Air Delivery (cfm)*
at Indicated External Static Pressure and Voltage (cont)
MODEL
48-
UNIT
VOLTS—
PHASE (60 Hz)
BLOWER
MOTOR
SPEED
COILt
EXTERNAL STATIC PRESSURE (in. wg)
208V
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
230V or 460V
0.0
0.1 0.2 0.3 0.4 0.5 0.6
0.7 0.8
Low Heat
Cool 1440
1435 1435
1430 1425
1420 1415
1410 1400
1395 1385
1380 1365
1355 1340
1330 1305
1290 1730
1725 1720
1710 1700
1685 1675
1660 1645
1625 1601
1585 1560
1545 1520
1495
KHA048 208/
230-3
1470
1445
Med Heat
Cooli 1755
1745 1740
1730 1725
1710 1700
1680 1665
1645 1625
1600 1580
1550 1530
1500 1470
1440 1970
1950 1945
1920 1910
1880 1875
1840 1825
1790 1775
1735 1720
1685 1660
1625 1600
1570
High Heat
Cool 1950
1925 1920
1890 1880
1850 1940
1810 1795
1765 1750
1715 1700
1665 1645
1615 1590
1560 2175
2130 2130
2085 2085
2035 2030
1980 1970
1920 1905
1855 1840
1790 1765
1720 1695
1650
KLA160 230-1
Low Heatt
Cool 1610
1595 1600
1585 1580
1575 1560
1550 1530
1515 1495
1475
High Heat
Coolj: 2375
2270 2280
2185 2185
2100 2095
2015 2000
1930 1905
1840
Low Heat
Cool 1880
1875 1875
1865 1860
1840 1825
1790 1770
1725 1700
1650
KHA060 230-1 Med Heat^:
Cool 2130
2075 2075
2025 2015
1965
1955
1900 1890
1835 1810
1760
High Heat
Coolj: 2345
2255 2260
2175 2180
2100 2095
2020 2010
1945 1930
1865
*Air delivery values are without air filter. Deduct field-supplied air filter
pressure drop to obtain external static pressure available for ducting
tHeating airflow values are with a dry coil Cooling airflow values are with
a wet coil.
frThese airflow values are at the factory heating and cooling motor speed
setting.
A dash (—) indicates portions of the table that are beyond the blower
motor capability or that are not applicable
NOTE: Do not operate the unit at a cooling airflow that is less than 350
fpm per each 12,000 Btuh of rated cooling capacity Indoor coil frosting
may occur at airflows below this point.
NOTE: The igniter continues to spark for approximately 10
seconds after burners are ignited.
LIMIT AND PRESSURE SWITCHES-Furnace limit
switch (see Fig. 10) closes gas valve if leaving-air tempera­
ture exceeds 175 F.
Normally closed limits switch completes control circuit
through pigtail lead W to gas valve 5F. See Fig. 10. Should
leaving-air temperature rise to 175 F, switch opens and W
control circuit breaks. Any interruption in W control circuit
instantly closes gas valve and stops gas flow to burners and
pilot. Blower motor continues to run until time-delay
sequence of heat relay is completed.
When air temperature at limit switch drops to the low-tem­
perature setting of limit switch, switch closes and com­
pletes W control circuit. Electric-spark ignition system
cycles emd unit returns to normeil heating operation.
BLOWER SAFETY SWITCH-BIower safety switch is a
temperature-actuated switch connected in parallel with con­
tacts of heat relay. Function of switch is to activate blower
should gas valve fail to close when thermostat is satisfied.
Safety switch is mounted on blower divider panel. When
temperature at safety switch reaches approximately 175 F,
switch closes to start blower. Switch opens when tempera­
ture at switch drops to approximately 116 F.
Cooling Section Start-Up and Adjustments
A CAUTION
Complete required procedures given in Unit Prepara­
tion section before starting unit.
Do not jumper any safety devices when operating unit.
Do not operate compressor when outdoor temperature
is below 55 F (single-phase units) or 40 F (3-phase
units).
Do not permit compressor to rapid cycle. Allow 5 min­
utes between cycles to prevent compressor damage.
CHECKING COOLING CONTROL OPERATION-Start
and check unit for proper cooling control operation as
follows:
1. Place room thermostat selector switch in OFF position.
Observe that blower motor starts when fan switch is
placed in ON position and shuts off when fan switch is
placed in AUTO, position.
2. Place selector switch in COOL position and fan switch
in AUTO, position. Set cooling control below room tem­
perature. Observe that compressor, condenser fan and
evaporator blower motors start. Observe that cooling
cycle shuts down when control setting is satisfied.
3. When using an automatic changeover room thermo­
stat, place both selector and fan switches in AUTO,
positions. Observe that unit operates in heating mode
when temperature control is set to call for heating
(above room temperature) and operates in cooling mode
when temperature control is set to call for cooling
(below room temperature).
CHECKING AND ADJUSTING REFRIGERANT
CHARGE—Refrigerant system is fully charged with R-22
refrigerant, tested and factory sealed. For most applica­
tions, factory charge is the correct amount for best perform­
ance; however, this charge may require a slight adjustment
to attain rated performance.
NOTE: Adjustment of refrigerant charge is not required
unless unit is suspected of not having proper R-22 charge.
For all applications, correct R-22 charge for best perform­
ance is charge that results in a suction gas superheat of 5 F
at compressor inlet when unit is operating at ARI rating
conditions of 95 F db outdoor and 80 F db/67F wb indoor.
A superheat charging label is attached to outside of com­
pressor access door. Label includes a Field Superheat
Charging Table and a Required Suction-Tube (F) tempera­
ture chart.
Table 7 is intended for use when minor unit charge adjust­
ments are required. For large adjustments, evacuate unit
and weigh in cheirge according to unit rating plate. Use
Table 7 to approximate charge if ARI rating conditions can-
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