Goodman Mfg IO-354B - Manual (Page 16)

16
L
UBRICATION
The fan shaft bearings, the 1 to 2 HP supply fan motors the
condenser fan motors and compressors are permanently lu-
bricated.
F
UNCTIONAL
P
ARTS
Refer to the unit Parts Catalog for a list of functional parts.
Parts are available from your distributor.
SERVICE
THE FOLLOWING INFORMATION IS FOR USE BY QUALI-
FIED SERVICE AGENCY ONLY: OTHERS SHOULD NOT
ATTEMPT TO SERVICE THIS EQUIPMENT.
Common Causes of Unsatisfactory Operation of Heat Pump
on the Heating Cycle.
I
NADEQUATE
A
IR
V
OLUME
T
HROUGH
I
NDOOR
C
OIL
When a heat pump is in the heating cycle, the indoor coil is
functioning as a condenser. The return air filter must always
be clean, and sufficient air volume must pass through the
indoor coil to prevent excessive discharge pressure, and high
pressure cut out.
O
UTSIDE
A
IR INTO
R
ETURN
D
UCT
Do not introduce cold outside air into the return duct of a heat
pump installation. Do not allow air entering the indoor coil to
drop below 65° F. Air below this temperature will cause low
discharge pressure, thus low suction pressure, and exces-
sive defrost cycling resulting in low heating output. It may
also cause false defrosting.
U
NDERCHARGE
An undercharged heat pump on the heating cycle will cause
low discharge pressure resulting in low suction pressure and
frost accumulation on the outdoor coil.
P
OOR
“T
ERMINATING
” S
ENSOR CONTACT
The unit’s defrost terminating sensor must make good ther-
mal contact with the outdoor coil tubing. Poor contact may
not terminate the unit’s defrost cycle quickly enough to pre-
vent the unit from cutting out on high discharge pressure.
M
ALFUNCTIONING
R
EVERSING
V
ALVE
- T
HIS MAY BE DUE TO
:
1. Solenoid not energized - In order to determine if the
solenoid is energized, touch the nut that holds the
solenoid cover in place with a screwdriver. If the nut
magnetically holds the screwdriver, the solenoid is
energized and the unit is in the cooling cycle.
2. No voltage at unit’s solenoid - Check unit voltage.
If no voltage, check wiring circuit.
3. Valve will not shift:
a. Undercharged - check for leaks;
b. Valve Body Damaged - Replace valve;
c. Unit Properly Charged - If it is on the heating cycle,
raise the discharge pressure by restricting airflow
through the indoor coil. If the valve does not shift,
tap it lightly on both ends with a screwdriver handle.
DO NOT TAP THE VALVE BODY. If the unit is on
the cooling cycle, raise the discharge pressure by
restricting airflow through the outdoor coil. If the valve
does not shift after the above attempts, cut the unit
off and wait until the discharge and suction pressure
equalize, and repeat above steps. If the valve does
not shift, replace it.