Carrier COMFORT 48EZ-A - Manual (Page 4)

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11. Set the temperature selector on room thermostat to desired
setting.
FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
1. If the main burners fail to light, or the blower fails to
start, shut down gas heating section and call your dealer for
service.
2. Never attempt to manually light the main burners on unit
with a match, lighter, or any other flame. If the electric
sparking device fails to light the main burners, refer to the
following shutdown procedures, then call your dealer as
soon as possible.
!
WARNING
Burners Gas Valve
Flue Hood
A09043
Fig. 4 -- Gas Heating/Electric Cooling Unit with Access Panel
Removed
To shut off unit gas heat:
FIRE, EXPLOSION, ELECTRICAL SHOCK
HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Do not turn off the electrical power to unit without first
turning off the gas supply.
!
WARNING
NOTE: If the unit is being shut down because of a malfunction,
call your dealer as soon as possible.
Should overheating occur or the gas supply fail to shut off, shut
off the external manual gas valve to the unit before shutting off
the electrical supply. Do not use this unit if any part has been under
water. Immediately call a qualified service technician to inspect the
unit and to replace any part of the control system and any gas
control which has been under water.
Refer to Fig. 6 while proceeding with the following steps.
1. Set the temperature selector on room thermostat to lowest
temperature setting and set system SWITCH to OFF.
2. Close the external manual shutoff valve.
3. Turn off the electrical power supply to the unit.
4. Remove the control access panel. (See Fig. 3.)
5. Move the selector switch on the internal gas valve to the
OFF position.
6. Replace the control access panel.
To start unit electric cooling:
Refer to Fig. 7 while proceeding with the following steps.
1. Set the temperature selector on room thermostat to highest
temperature setting and set system SWITCH to OFF.
2. Close the external manual shutoff valve, if not already
closed.
3. Turn ON the electrical power supply to the unit.
4. Set system switch to COOL.
5. Set the temperature selector on room thermostat slightly be-
low the room temperature to start unit.
To shut off unit electric cooling:
Refer to Fig. 8 while proceeding with the following steps.
1. Set the temperature selector on room thermostat to highest
temperature setting and set system SWITCH to OFF.
2. Close the external manual shutoff valve, if not already
closed.
3. Turn off the electrical power supply to the unit.
NOTE: Heat Pump heating mode procedure is similar to electric
cooling mode except thermostat mode is HEAT and thermostat
must operate on first stage heating above the balance point that has
been determined by the Dealer.
OPERATING YOUR UNIT
The operation of your unit is controlled by the indoor temperature
control (thermostat). You simply adjust the thermostat and it
maintains the indoor temperature at the level you select. Most
thermostats of heating and cooling systems have 3 controls: a
temperature control selector, a FAN control, and a SYSTEM or
MODE control. Refer to your thermostat owner’s manual for more
information.
To better protect your investment and to eliminate unnecessary
service calls, familiarize yourself with the following facts:
1. During heat pump heating, increasing the thermostat setting
more than 2_F (1.1_C) may cause the supplemental gas heat
to be turned on for a short period of time to satisfy the
thermostat. Needless use of the supplementary heat reduces
potential energy savings.
2. Ice or frost tends to form on the coil during winter heating
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!
Cooling Mode
With the SYSTEM control set to COOL, your unit will run in
cooling mode until the indoor temperature is lowered to the level
you have selected. On extremely hot days, your unit will run for
longer periods at a time and have shorter “off” periods than on
moderate days.
Heat Pump Heating Mode
With the SYSTEM or MODE control of your indoor thermostat set
to HEAT, your unit will run in heat pump heating mode until room
temperature is raised to the level you have selected. Of course, your
system will run for longer periods to maintain a comfortable
environment on cooler days and nights than on moderate ones.
Gas Heat Mode
Your heat pump is your primary heating source. Your system is
also equipped with a supplemental gas heating source. On cold
days and nights, your system will automatically turn on the
supplemental heat in order to maintain the level of comfort you
have selected.
When your heat pump needs additional heat to keep you
comfortable, your thermostat will turn on the supplemental gas
heat.