Operating Your Air Conditioner; Cooling Cycle; Heating Cycle; Performing Routine Maintenance - Carrier 38TDA Operating And Maintaining

LCD READOUT DISPLAYS
CURRENT ROOM TEMPERATURE,
DESIRED ROOM TEMPERATURE,
UNIT MODE SETTING,
AND FAN MODE SETTING
Thermostat
RESET/FILTER FAN MODE
RESET FILTER BUTTON FAN BUTTON CHOOSES
RESTARTS THE TIMER BETWEEN ON OR AUTO
THAT CALCULATES FAN OPERATION
THE NEXT AIR FILTER
CHANGE OR CLEANING
Fig. 2—Typical Non-Programmable
Thermostat

OPERATING YOUR AIR CONDITIONER

The operation of your air conditioning system is controlled by
the indoor thermostat. Simply adjust the thermostat to maintain
the indoor temperature at the level you select. Most thermostats
have three controls: the temperature, FAN, and mode selectors.
The temperature selector could be a dial, lever, or buttons that
allow you to establish the degree of temperature that you wish
to maintain for your personal comfort. Some thermostats pos-
sess two temperature control selectors: one for setting the tem-
perature desired during the cooling cycle, and one to set the
heating operation temperature.
The FAN button offers two options for controlling the blower;
AUTO and ON. When set to AUTO, the blower will run only
while the thermostat operates the cooling or heating section.
When the FAN is set to the ON position, the blower will run
continuously—regardless of whether the cooling or heating sec-
tion is operating.
Typically, the MODE button on your thermostat offers the follow-
ing selections; COOL, OFF, and HEAT. Your thermostat may also
have a fourth selection, AUTO. Neither the cooling nor heating
section will operate when the MODE is set to the OFF position.
With the MODE set to COOL, the cooling section of your comfort
system will operate when the indoor temperature rises above the
level that you wish to maintain. With the MODE set to HEAT, the
heating section will operate automatically when the indoor tem-
perature falls below the level that you have selected.
The AUTO selection found on some thermostats provides for auto-
matic changeover between cooling and heating cycles. With the
MODE set to AUTO, the cooling section will operate when the
indoor temperature rises above the thermostat cooling temperature
setting, or the heating section will operate when the indoor temper-
ature drops below the thermostat setting for the heating cycle.
NOTE: Your 2-speed air conditioning system has several special
features built in to protect the unit.
• 5-MINUTE TIME DELAY—Unit will delay operation upon
initial start-up or short cycling of the indoor thermostat.
• 1-MINUTE TIME DELAY—When changing speeds from
low to high, or high to low, there is a 1-minute time delay. Dur-
ing the speed change delay, the outdoor fan will continue to run.
• 2-MINUTE LOW-SPEED MINIMUM—If the unit has not
operated within the past 30 minutes, upon the next cooling
demand it will operate for a minimum of 2 minutes on low speed.
If you wish to program your accessory electronic indoor ther-
mostat, refer to thermostat Installation Instructions.
UP AND DOWN
BUTTONS INCREASE
OR DECREASE THE
DESIRED TEMPERATURE
SETTINGS
MODE BUTTON SELECTS
BETWEEN OFF, HEAT,
COOL, AND AUTO OPERATION
MODE BUTTON SELECTS
BETWEEN OFF, HEAT,
PROGRAM BUTTONS COOL, AND AUTO
FOR PROGRAMMING OPERATION
HEATING/COOLING
CYCLES
Programmable
Thermostat
COPY PREVIOUS DAY PROGRAM
CHANGE DAY
RESET FILTER
SET TIME/TEMP RESET FILTER
SET TIME
BUTTON
RESET FILTER BUTTON
RESTARTS THE TIMER
THAT CALCULATES
THE NEXT AIR FILTER
CHANGE OR CLEANING
Fig. 3—Typical Programmable Thermostat

COOLING CYCLE

When operating in the cooling cycle, your air conditioner will
run until the indoor temperature is lowered to the level you have
selected. On extremely hot days, your air conditioner will run
for longer periods at a time and have shorter "off" periods than
on moderate days.
The following conditions typically add extra heat and/or humid-
ity to your home and make your cooling unit work longer to keep
your home comfortable:
• Entrance doors are frequently opened and closed
• Laundry appliances are being operated
• A shower is running
• More than the usual number of people are present in the home
• More than the normal number of electric lights are in use
• Drapes are open on the sunny side of the home

HEATING CYCLE

With the MODE of your indoor thermostat set to HEAT, the
heating section of your home comfort system will operate until
room temperature is raised to the level you have selected. Of
course, the heating unit will have to operate for longer periods
to maintain a comfortable environment on cooler days and
nights than on moderate ones.
Refer to your furnace User's Manual for specific information on
heating operation.

PERFORMING ROUTINE MAINTENANCE

With proper maintenance and care, your air conditioning unit
will operate economically and dependably. Maintenance can be
accomplished easily by referring to the following directions.
However, before performing maintenance, consider these
important safety precautions
!
To prevent personal injury or death disconnect all
electrical power to the air conditioner before re-
moving access panels to perform maintenance.
Disconnect power to both the indoor and outdoor
units. Note: there may be more than 1 electrical
disconnect switch.
3
LCD READOUT DISPLAYS
CURRENT ROOM TEMPERATURE,
DESIRED ROOM TEMPERATURE
OR OUTDOOR TEMPERATURE,
UNIT MODE SETTING,
FAN MODE SETTING,
AND TIME OF DAY
MODE
UP AND DOWN
BUTTONS INCREASE
END FAN
OR DECREASE THE
DESIRED TEMPERATURE
SETTINGS
HOLD
HOLD
FAN BUTTON CHOOSES
BETWEEN ON OR AUTO
FAN OPERATION
HOLD BUTTON MAINTAINS
THE CURRENT TEMPERATURE
AND OVERRIDES PROGRAMMED
TEMPERATURE CHANGES
UNTIL RESET
WARNING