2
 
which allows individual control over the temperatures of sep-
arate areas of your home or office.
• Your heat pump will remove humidity from your home or  
office during the cooling season. After a few minutes of oper-
ation, you should be able to see water trickle from the conden-
sate 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 environment.
• During the heating cycle, air from your registers may seem 
cooler than you might first expect. This is because your heat 
pump delivers a constant flow of air at around 90°F to 105°F 
instead of sudden bursts of hot air as with a conventional fur-
nace. This air may feel cool because it is slightly cooler than 
your skin temperature. However, it is sufficiently warm to 
keep you comfortable.
• Ice or frost will tend to form on the coil during the winter heat-
ing operation. Your heat pump is designed to automatically melt 
the ice. When in this defrost cycle, it is normal for steam or fog to 
rise from the outdoor unit. Do not be alarmed!
• Do not operate your unit in the cooling mode when outdoor 
temperatures are below 55°F  unless your unit was modified 
for low-ambient operation.
• Do not operate your unit in the heating mode when outdoor 
temperatures are above 66°F  unless you set your thermostat 
to emergency heat mode.
OPERATING YOUR HEAT PUMP
 
The operation of your heat pump system 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 heat pump systems have 3 controls: a temper-
ature control selector, a FAN control, and a SYSTEM or 
MODE control. Refer to your T-stat owner’s manual for more 
information.
Fig. 2—Typical Installation
INDOOR
THERMOSTAT
DISCONNECT
PER NEC
FROM
POWER
SOURCE
RETURN
AIR
TOP COVER
 
 
YOUR COMFORT SYSTEM
Identifying Your System
 
Take the time to familiarize yourself with your packaged heat 
pump system. This knowledge will be of use in understanding 
the basic operation of your new heat pump. 
The unit has a rating plate affixed to it which provides neces-
sary information for specific identification of a unit. You should 
familiarize yourself with the product, model, and serial num-
bers listed on each rating plate. Record them for future refer-
ence on the last page of this booklet.
IMPORTANT FACTS
 
To better protect your investment and to eliminate unnecessary 
service calls, familiarize yourself with the following facts:
• Your heat pump system should never be operated without a 
clean air filter properly installed. Plan to inspect the filter peri-
odically. 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 registers. Restricted airflow lessens the 
unit’s efficiency and life span.
• The outdoor unit must have unrestricted airflow. Do not cov-
er the unit, lean anything against it, or stand on 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, etc.
• Your multipurpose indoor thermostat is the control center 
for your heat pump system. You should familiarize yourself 
with its proper operation. Attempting to control the system by 
other means—for instance, switching the electrical supply 
power ON and OFF—may cause damage to the unit. (See 
Fig. 3.)
• During heating, increasing the thermostat setting more than 
2º may cause the supplemental heaters to be turned on for a 
short period of time to satisfy the thermostat. Needless use of 
the supplementary heat reduces potential energy savings.
• 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 your home or office, placement of reg-
isters, etc. These air pockets may be too cool or warm for your 
liking. Continuous fan operation minimizes any temperature 
differences. Also, systems equipped with electronic or 
mechanical air cleaners and/or humidifiers offer the added 
benefits of having the air continuously cleaned year-round and 
humidified during the winter season.
• A system equipped with a heat or energy recovery ventilator 
offers the advantage of exhausting stale air from your home or 
office and allowing fresh air in from the outdoors while mini-
mizing heat loss.
• Your system may also be equipped with a zoning system 
WARNING
 
To prevent serious injury, death, or property dam-
age, read and follow all instructions and warnings,
including labels shipped with or attached to unit
before operating your new heat pump.
!
Fig. 3—Carrier Non-Programmable T-stat