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WELCOME TO EFFICIENT
YEAR-ROUND COMFORT
Congratulations on your excellent choice and sound invest-
ment in home comfort!
Your new dual fuel heat pump represents both the latest in
engineering development and the culmination of many years
of experience from one of the most reputable manufacturers
of comfort systems.
Your new unit is among the most reliable home comfort prod-
ucts available today. To assure its dependability, spend just
a few minutes with this booklet now. Learn about the op-
eration of your dual fuel heat pump and the small amount of
maintenance it takes to keep it operating at its peak
efficiency.
With minimal care, your dual fuel heat pump will provide
you and your family with satisfying home comfort — both
now and for years to come.
IMPORTANT FACTS
To better protect your investment and to eliminate unnec-
essary service calls, familiarize yourself with the following
facts:
Improper installation, adjustment, alteration, service, main-
tenance, or use can cause explosion, fire, electrical shock,
or other conditions which may cause personal injury or
property damage. Refer to this manual. For assistance
or additional information consult a qualified installer,
service agency, distributor, or branch. The qualified in-
staller or agency must use only factory-authorized kits
or accessories when modifying this product.
• Your dual fuel heat pump system should never be oper-
ated without a clean air filter properly installed. Plan to in-
spect the filter periodically. A clogged air filter will increase
operating costs and shorten the life of the unit.
• Supply-air and return-air registers should not be blocked.
Drapes, furniture, and toys are some of the items commonly
found obstructing grilles. Restricted airflow lessens the unit’s
efficiency and life span.
• Outdoor units must have unrestricted airflow. Do not cover
the unit, lean anything against it, or stand upon it. Do not
allow grass clippings, leaves, or other debris to accumulate
around or on top of the unit. Maintain a 12-in. minimum
clearance between the outdoor unit and tall grass, vines, shrubs,
et cetera.
• Your multipurpose indoor thermostat is the control center
for your dual fuel heat pump system. You should familiarize
yourself with its proper operation. Attempting to control the
system by other means — for instance, switching the elec-
trical supply power ON and OFF — may cause damage to
the unit.
• Thermostat ‘‘jiggling’’ causes rapid-cycling, which is po-
tentially damaging to the compressor. Do not move the tem-
perature selector on the thermostat for any reason for at least
5 minutes after the compressor has shut off.
• You may find that you can maintain greater personal com-
fort by running the fan continuously. ‘‘Air pockets’’ can form
due to the structure of the building, placement of registers,
et cetera. These air pockets may be too cool or warm
for your liking. Continuous fan operation minimizes any tem-
perature differences. Also, systems equipped with electronic
air cleaners and/or humidifiers offer the added benefits of
having the air continuously cleaned year-round, and humidi-
fied during the winter season.
• Your dual fuel heat pump will remove humidity from your
home during the cooling season. After a few minutes of op-
eration, you should be able to see water trickle from the con-
densate drain. Check this occasionally to be sure the drain
system is not clogged. Of course, don’t expect to see much
drainage if you live in a very dry climate.
OPERATING YOUR DUAL FUEL HEAT PUMP
The operation of your dual fuel heat pump is controlled by
the indoor thermostat. You simply adjust the thermostat and
it maintains the indoor temperature at the level you select.
Most thermostats for the dual fuel heat pump systems
include temperature control selector, FAN switch, and
SYSTEM switch. EMERGENCY HEAT (EM HEAT) set-
ting also is provided with the SYSTEM switch. See Fig. 1.
The temperature control selector is a dial or lever that allows
you to establish the temperature that you wish to maintain
for your personal comfort. Some thermostats possess two tem-
perature control selectors: one for setting the temperature de-
sired during the cooling cycle, and one to set the heating
operation temperature. Typical settings are 78 degrees Fahr-
enheit for cooling and 68 degrees for heating.
The FAN switch offers two options for controlling the blower:
AUTO and ON. When set to AUTO, the blower will run dur-
ing the time the dual fuel heat pump is operating. When the
FAN switch is set at the ON position, the blower will run
continuously.
Typically, the SYSTEM switch on your thermostat offers the
following selections: COOL, OFF, HEAT, and EMER-
GENCY HEAT. Your thermostat may also have another se-
lection, AUTO. The heat pump will not operate when the
SYSTEM switch is set at the OFF position. With the SYS-
TEM switch set at COOL, your heat pump will operate in its
cooling mode when the indoor temperature rises above the
level that you wish to maintain. With the SYSTEM switch
set at the HEAT position, your dual fuel heat pump will pro-
vide warmth whenever the indoor temperature falls below
the level that you have selected.
The AUTO selection found on some thermostats provides
for automatic changeover between cooling and heating cycles.
With the SYSTEM switch set in the AUTO position, the cool-
ing mode is activated when the indoor temperature rises above
the thermostat cooling temperature setting, or the heating mode
will be activated when the indoor temperature drops below
the thermostat setting for the heating cycle.
Your home comfort system includes supplementary gas heat.
Your system will turn on gas heat only as necessary to meet
your heating needs during defrost cycles or when outdoor
temperatures are low. In the event of a heat pump malfunc-
tion, you can use the EMERGENCY HEAT setting on your
thermostat to manually select gas heat. Heat pump heating
is deactivated when EMERGENCY HEAT is selected. If it
becomes necessary to use EMERGENCY HEAT to provide
heat, call your dealer for service as soon as is practical.
See your thermostat owner’s manual for additional
information.
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