Carrier WEATHERMASTER 50HJQ016 Product Data Download Page 167

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the reversing valve solenoids (RVS1 and RVS2), and ener-
gizes the electric heat. The outdoor-fan motor will stop.
The unit continues to defrost either until the coil tempera-
ture as measured by DFT1 or DFT2 reaches 65 F, or until
unit completes a 10-minute defrost cycle.
During the defrost mode, when a circuit defrosts, RVS will
oscillate between heating and cooling modes until defrost

mode is complete. This will prevent the head pressure
from getting too high.
At the end of the defrost cycle, the electric heaters (if appli-
cable) will be deenergized, the reversing valve solenoids will
be energized, and the outdoor fans will start.

Application data

Outdoor installation —

Units approved for outdoor in-

stallation only.

Ductwork —

Secure vertical discharge ductwork to roof

curb. For horizontal discharge applications, either attach
ductwork to unit, or use field-supplied flanges attached to
the horizontal discharge openings and attach all ductwork
to flanges.

Horizontal EconoMi$er2 —

A field-installed accessory

is available for horizontal discharge applications. Field-
installed power exhaust accessory also available for vertical
or horizontal EconoMi$er2 applications.

Thru-the-bottom power connections —

For applica-

tions requiring thru-the-bottom connections, Carrier acces-
sory thru-the-bottom package must be purchased to ensure
proper connections.

Thermostat —

Use of 2-stage heating and cooling ther-

mostat is recommended for all units. A 2-stage cooling
thermostat is required on units with accessory economizer
to provide integrated cooling. A two-stage thermostat is re-
quired for all 50HJQ008-016 units.

Heating-to-cooling changeover —

All units are auto-

matic changeover from heating to cooling when automatic
changeover thermostat and subbase are used.

Airflow —

Units are draw-thru on cooling and blow-thru

on heating.

Maximum airflow —

To minimize the possibility of con-

densate blow-off from indoor coil, airflow through units
should not exceed 500 cfm/ton.

Minimum airflow —

For cooling, minimum airflow is

300 cfm/ton. For 50TFQ units with electric heating,
required minimum cfm is 900 for 50TFQ004; 1200 for
50TFQ005; 1500 for 50TFQ006; 1800 for 50TFQ007;
2250 for 50TFQ008; 2500 for 50TFQ009; and 3000 for
50TFQ012, with the following exceptions:

For 50HJQ units with electric heating, required mini-

mum cfm is 900 for 50HJQ004; 1200 for 50HJQ005;
1500 for 50HJQ006; 1700 for 50HJQ007; 2250 for

50HJQ008; 2500 for 50HJQ009; 3000 for 50HJQ012;
3900 for 50HJQ014; and 4500 for 50HJQ016, with the
following exceptions:

Minimum ambient cooling operating temperature
—

The minimum temperature for standard size 004-012

units is 25 F. With accessory Motormaster® I, II, or IV
control, units can operate at outdoor temperatures down
to –20 F.

Unit sizes 014 and 016 are designed to operate at out-

door temperatures down to 40 F (4.4 C). With accessory
Motormaster I control, units can operate at outdoor tem-
peratures down to –20 F.

Internal unit design —

Due to Carrier’s internal unit

design (draw-thru over the motor), air path, and specially
designed motors, the full horsepower (maximum
continuous bhp) listed in the Physical Data table and the
notes following each Fan Performance table can be utilized
with confidence.

Using Carrier motors with the values listed in the Physi-

cal and Fan Performance Data tables

will not

result in

nuisance tripping or premature motor failure. The unit
warranty will not be affected.

Condensate drain pan

A sloped condensate drain pan is supplied on all units. The
condensate pan must be externally trapped. Condensate
drains are located on both the bottom and end of the unit.

Motor data

Due to Carrier’s internal unit design (draw-thru over the
motor), air path, and specially designed motors, the full
horsepower (maximum continuous bhp) listed in the Physi-
cal Data tables and the notes following each Fan Perfor-
mance table can be utilized with extreme confidence.

Using Carrier motors to the values listed in the Physical

Data, Fan Performance, and Evaporator-Fan Motor Data
tables

will not

result in nuisance tripping or premature

motor failure. In addition, the unit warranty will not be
affected.

UNIT

50TFQ

UNIT

VOLTAGE

HEATER

UNIT

CONFIGURATION