Daikin DSC Series Installation Instructions Manual page 14

should be cleaned or replaced. These few steps will help to keep
the product up time to a maximum. The Service section that fol-
lows should help in identifying problems if the unit does not oper-
ate properly.
F
ILTERS
T
O PREVENT PROPERTY DAMAGE DUE TO FIRE AND LOSS OF
EQUIPMENT EFFICIENCY OR EQUIPMENT DAMAGE DUE TO DUST AND LINT
BUILD UP ON INTERNAL PARTS, NEVER OPERATE UNIT WITHOUT AN AIR
FILTER INSTALLED IN THE RETURN AIR SYSTEM.
Every application may require a different frequency of replace-
ment of dirty filters. Filters must be replaced at least every three
(3) months during operating seasons.
Dirty filters are the most common cause of inadequate heating or
cooling performance. Filter inspection should be made at least
every two months; more often if necessary because of local condi-
tions and usage.
Dirty throwaway filters should be discarded and replaced with a
new, clean filter.
Disposable return air filters are supplied with this unit. See the
unit Specification Sheet or Technical Manual for the correct size
and part number. To remove the filters, remove the filter access
panel on return side of the unit.
C F M
ABINET INISH AINTENANCE
Use a fine grade automotive wax on the cabinet finish to maintain
the finish's original high luster. This is especially important in in-
stallations with extended periods of direct sunlight.
C O C (Q
LEAN UTSIDE OIL UALIFIED
The coil with the outside air flowing over it should be inspected
annually and cleaned as frequently as necessary to keep the finned
areas free of lint, hair and debris.
L
UBRICATION
The fan shaft bearings , the 1 to 2 HP supply fan motors, the con-
denser fan motors and compressors are permanently lubricated.
F P
UNCTIONAL ARTS
Refer to the unit Parts Catalog for a list of functional parts. Parts
are available from your distributor.
TROUBLESHOOTING
THE FOLLOWING INFORMATION IS FOR USE BY QUALIFIED SER-
VICE AGENCY ONLY: OTHERS SHOULD NOT ATTEMPT TO SERVICE
THIS EQUIPMENT.
Common Causes of Unsatisfactory Operation of Heat Pump on the
Heating Cycle.
I A V T
NADEQUATE IR OLUME HROUGH
When a heat pump is in the heating cycle, the indoor coil is func-
tioning as a condenser. The return air filter must always be clean,
and sufficient air volume must pass through the indoor coil to pre-
vent excessive discharge pressure, and high pressure cut out.
CAUTION
S O )
ERVICER NLY
I C
NDOOR OIL
O A R
UTSIDE IR INTO ETURN
Do not introduce cold outside air into the return duct of a heat
pump installation. For units with 2-speed motors, do not allow air
entering the indoor coil to drop below 65° F. Air below this tem-
perature will cause low discharge pressure, thus low suction pres-
sure, and excessive 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 ac-
cumulation on the outdoor coil.
P "T " S
OOR ERMINATING ENSOR CONTACT
The unit's defrost terminating sensor must make good thermal
contact with the outdoor coil tubing. Poor contact may not termi-
nate the unit's defrost cycle quickly enough to prevent the unit
from cutting out on high discharge pressure.
M R
ALFUNCTIONING EVERSING
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.
14
D
UCT
V - T
ALVE HIS MAY BE DUE TO
: