Carrier SYNERGY 38YD - Manual (Page 3)

Fig. 2—Auto Changeover
Thermostat
for steam or fog to rise from the outdoor unit. Do not be
alarmed!
• Do not operate your unit in cooling mode when outdoor tem­
peratures are below 55 °P.
• Do not operate your unit in heating mode when outdoor tem­
peratures are above 66°F.
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: the tem­
perature control selector, FAN switch, and SYSTEM switch.
The temperature control selector is a dial or lever that allows
you to establish the degree of temperature that you wish to
maintain for your personal comfort. Some thermostats possess
2 temperature control selectors: one for setting the temperature
desired during the cooling cycle, and one to set the heating oper­
ation temperature. TVpical settings are 78°F for cooling and
68 °F for heating.
The FAN switch offers 2 options for controlling the blower:
AUTO and ON. When set to AUTO, the blower will run during
the time the 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: EM HEAT, HEAT, OFF, AUTO, and
COOL. The heat pump will not operate when the SYSTEM
switch is set at the OFF position. With the SYSTEM 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 heat pump will provide warmth whenever the indoor tem­
perature 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 be­
low the thermostat setting for the heating cycle.
A91281
Fig. 3—Night Setback
Thermostat
If equipped with and you wish to program your accessory elec­
tronic indoor thermostat, please refer to thermostat installa­
tion instructions.
Depending on your typical winter heating needs, your home
comfort system may include a supplementary heating source.
When the system switch is set to HEAT, your heat pump will
operate normally and supplementary heat will be added as
needed. With the system switch set to EM HEAT, the heat
pump will turn off and the supplementary heat source will sup­
ply all your home heating needs.
NOTE: Your two-speed heat pump 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 de­
mand, it will operate for a minimum of 2 minutes on low speed.
COOLING CYCLE
When operating in the cooling cycle, your heat pump will run
until the indoor temperature is lowered to the level you have se­
lected. On extremely hot days, your conditioner will run for
longer periods at a time and have shorter “off’ periods than on
moderate days.
The following are typical conditions that add extra heat and/or
humidity to your home. Your cooling unit will work longer to
keep your home comfortable under these conditions:
• 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 SYSTEM switch of your indoor thermostat set to the
HEAT position, the heating section of your home comfort sys­