Daikin DTC Series, Installation Instructions Manual

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pump. It is a good practice to provide supplementary heat for
all heat pump installations in areas where the temperature
drops below 45° F. It is also a good practice to provide
sufficient supplementary heat to handle the entire heating
requirement should there be a component failure of the heat
pump, such as a compressor, or refrigerant leak, etc.
Since the temperature of the refrigerant in the outdoor coil
on the heating cycle is generally below freezing point, frost
forms on the surfaces of the outdoor coil under certain weather
conditions of temperature and relative humidity. Therefore, it
is necessary to reverse the flow of the refrigerant to provide
hot gas in the outdoor coil to melt the frost accumulation. This
is accomplished by reversing the heat pump to the cooling
cycle. At the same time, the outdoor fan stops to hasten
the temperature rise of the outdoor coil and lessen the time
required for defrosting. The indoor blower continues to run
and the supplementary heaters are energized.
Defrost Control
During operation the power to the circuit board is controlled
by a temperature sensor, which is clamped to a feeder tube
entering the outdoor coil. Defrost timing periods of 30,60 and
90 minutes may be selected by connecting the circuit board
jumper to 30, 60 and 90 respectively. Accumulation of time
for the timing period selected starts when the sensor closes
(approximately 31° F), and when the wall thermostat calls for
heat. At the end of the timing period, the unit’s defrost cycle
will be initiated provided the sensor remains closed. When
the sensor opens (approximately 75° F), the defrost cycle is
terminated and the timing period is reset. If the defrost cycle
is not terminated due to the sensor temperature, a ten minute
override interrupts the unit’s defrost period.
MAINTENANCE
WARNING
HIGH VOLTAGE!
Disconnect all power before servicing or
installing this unit. Multiple power sources
may be present. Failure to do so may cause
property damage, personal injury or death.
WARNING
To prevent personal injury or death due to inproper
installation, adjustment, alteration, service or
maintenance, refer to this manual. For additional
assistance or information, consult a qualified
installer, service agency or the gas supplier.
CAUTION
Sheet metal parts, screws. clips and similar items
inherently have sharp edges, and it is necessary that
the installer and service personnel exercise caution.
The Self Contained Packaged Air Conditioner and Heat Pump
should operate for many years without excessive service calls
if the unit is installed properly. However it is recommended
that the homeowner inspect the unit before a seasonal start
up. The coils should be free of debris so adequate airflow is
achieved. The return and supply registers should be free of
any obstructions. The filters should be cleaned or replaced.
These few steps will help to keep the product up time to a
maximum. The Service section that follows should help in
identifying problems if the unit does not operate properly.
Filters
CAUTION
To 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
replacement 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 conditions 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.
Cabinet Finish Maintenance
Use a fine grade automotive wax on the cabinet finish to maintain
the finish’s original high luster. This is especially important in
installations with extended periods of direct sunlight.
Clean Outside Coil (Qualified Servicer Only)
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.
Lubrication
The fan shaft bearings ,the 1 to 2 HP supply fan
motors, the condenser fan motors and compressors are
permanently lubricated.
Functional Parts
Refer to the unit Parts Catalog for a list of functional parts.
Parts are available from your distributor.