Gas Input; Indoor Airflow; Check Defrost Thermostat; Puronr Items - Bryant LEGACY 677C E Series Installation Instructions Manual

A
MAX DISTANCE BETWEEN TOP OF FAN GRILLE AND BOTTOM OF FAN BLADE
SIZE
24
30
36
42
48
60

Gas Input

The gas input does not require checking unless improper heating
performance is suspected. If a problem exists, refer to the Start- -Up
section.

Indoor Airflow

The heating and/or cooling airflow does not require checking
unless improper performance is suspected. If a problem exists, be
sure that all supply- - and return- -air grilles are open and free from
obstructions, and that the air filter is clean. When necessary, refer to
the Indoor Airflow and Airflow Adjustments section to check the
system airflow.

Check Defrost Thermostat

The defrost thermostat is usually located on the lowest liquid
leaving circuit of the left condenser coil (see Fig. 22). The
thermostat closes at 32_F (0_C) and opens at 65_F (18_C).
Puron Items
Metering Device (Thermostatic Expansion Valve &
Piston)
This unit uses both a hard shutoff, balance port TXV in the indoor
coil and a piston in each side of the outdoor coil. The TXV
maintains a constant superheat at the evaporator coil exit (cooling
mode) resulting in higher overall system efficiency.
Pressure Switches
Pressure switches are protective devices wired into control circuit
(low voltage). They shut off compressor if abnormally high or low
pressures are present in the refrigeration circuit. These pressure
switches are specifically designed to operate with Puron (R- -410A)
systems. R- -22 pressure switches must not be used as replacements
for the Puron (R- -410A) system.
Loss of Charge Switch
This switch is located on the liquid line and protects against low
suction pressures caused by such events as loss of charge, low
airflow across indoor coil, dirty filters, etc. It opens on a pressure
drop at about 20 psig. If system pressure is above this, switch
should be closed. To check switch:
1. Turn off all power to unit.
2. Disconnect leads on switch.
MOTOR
IN.
9.0
7.1
7.6
7.6
7.6
7.6
Fig. 23 - - Fan Blade Position
3. Apply ohm meter leads across switch. You should have
NOTE:
system under pressure, it is not advisable to remove this device for
troubleshooting unless you are reasonably certain that a problem
exists. If switch must be removed, remove and recover all system
charge so that pressure gauges read 0 psig. Never open system
without breaking vacuum with dry nitrogen.
High- -Pressure Switch
The high- -pressure switch is located in the discharge line and
protects against excessive condenser coil pressure. It opens at 650
psig.
High pressure may be caused by a dirty outdoor coil, failed fan
motor, or outdoor air recirculation. To check switch:
1. Turn off all power to unit.
2. Disconnect leads on switch.
3. Apply ohm meter leads across switch. You should have
Copeland Scroll Compressor (Puron Refrigerant)
The compressor used in this product is specifically designed to
operate with Puron (R- -410A) refrigerant and cannot be
interchanged.
The compressor is an electrical (as well as mechanical) device.
Exercise extreme caution when working near compressors. Power
should be shut off, if possible, for most troubleshooting techniques.
Refrigerants present additional safety hazards.
51
FAN GRILLE
MOTOR SHAFT
"A"
continuity on a good switch.
Because these switches are attached to refrigeration
continuity on a good switch.
WARNING
!
EXPLOSION HAZARD
Failure to follow this warning could
result in personal injury or death
and/or property damage.
Wear safety glasses and gloves when
handling refrigerants. Keep torches
and other ignition sources away from
refrigerants and oils.
A08505
MM
228
180
193
193
193
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