Testing Crankcase Heater (Optional Item); Checking Reversing Valve And Solenoid; Testing Defrost Control; S-17D Operation Test - Goodman ComfortNet ASXC160**1AA Series Service Instructions Manual

SERVICING

S-17D OPERATION TEST

If the voltage, capacitor, overload and motor winding test fail
to show the cause for failure:
HIGH VOLTAGE!
Disconnect ALL power before servicing
or installing. Multiple power sources
may be present. Failure to do so may
cause property damage, personal injury
or death.
1. Remove unit wiring from disconnect switch and wire a
test cord to the disconnect switch.
NOTE: The wire size of the test cord must equal the line wire
size and the fuse must be of the proper size and type.
2. With the protective terminal cover in place, use the three
leads to the compressor terminals that were discon-
nected at the nearest point to the compressor and
connect the common, start and run clips to the respec-
tive leads.
3. Connect good capacitors of the right MFD and voltage
rating into the circuit as shown.
4. With power ON, close the switch.
WARNING
Line Voltage now present.
A. If the compressor starts and continues to run, the cause
for failure is somewhere else in the system.
B. If the compressor fails to start - replace.
COPELAND COMPRESSOR
03 A
YEAR MONTH
S-18 TESTING CRANKCASE HEATER (OP-
TIONAL ITEM)
The crankcase heater must be energized a minimum of four
(4) hours before the condensing unit is operated.
Crankcase heaters are used to prevent migration or accumu-
lation of refrigerant in the compressor crankcase during the
off cycles and prevents liquid slugging or oil pumping on start
up.
A crankcase heater will not prevent compressor damage due
to a floodback or over charge condition.
12345 L
PLANT
SER IAL
NUMBER
WARNING
Disconnect ALL power before servicing.
1. Disconnect the heater lead in wires.
2. Using an ohmmeter, check heater continuity - should
test continuous. If not, replace.
NOTE: The positive temperature coefficient crankcase heater
is a 40 watt 265 voltage heater. The cool resistance of the
heater will be approximately 1800 ohms. The resistance will
become greater as the temperature of the compressor shell
increases.
S-21 CHECKING REVERSING VALVE AND
SOLENOID
Occasionally the reversing valve may stick in the heating or
cooling position or in the mid-position.
When stuck in the mid-position, part of the discharge gas
from the compressor is directed back to the suction side,
resulting in excessively high suction pressure. An increase
in the suction line temperature through the reversing valve
can also be measured. Check operation of the valve by
starting the system and switching the operation from COOL-
ING to HEATING cycle.
If the valve fails to change its position, test the voltage (24V)
at the valve coil terminals, while the system is on the
COOLING cycle.
All heat pumps and ComfortNet
legacy - If no voltage is registered at the coil terminals,
check the operation of the thermostat and the continuity of
the connecting wiring from the "O" terminal of the thermostat
to the unit.
ComfortNet heat pumps only - Check voltage (24VAC) at
the non-insulated terminal E22 on the UC control board
(RVS on silkscreen) and "C" terminal on the 7-pin or 4-pin
connector on the UC control
If voltage is registered at the coil, tap the valve body lightly
while switching the system from HEATING to COOLING,
etc. If this fails to cause the valve to switch positions, remove
the coil connector cap and test the continuity of the reversing
valve solenoid coil. If the coil does not test continuous -
replace it.
If the coil test continuous and 24 volts is present at the coil
terminals, the valve is inoperative - replace it.
S-24 TESTING DEFROST CONTROL
LEGACY MODELS:
COMFORTNET TM UNITS:
To check the defrost control for proper sequencing, proceed
as follows: With power ON; unit not running.
1. Set thermostat to call for heating.
TM
heat pumps wired in
85