Manual 2100-279
Page 3
3.1
BASIC OPERATION – HEATING CYCLE
This furnace is operated by an Electronic Blower Control
(EBC) and a gas control system which controls all functions
of the furnace.
On a call for heat from the thermostat, the EBC first turns on
the inducer motor. The pressure switch then closes
signaling the ignition control to proceed with ignition
function.
The ignition system consists of an intermittent pilot with a
hot surface igniter to light pilot burner, senses flame, and
then main gas valve opens with pilot flame lighting main
burners.
There is a 60 second delay after main burner is on until the
comfort air blower starts on heating (low) speed. After the
thermostat is satisfied, the burners will go off as gas
valve closes. The inducer will continue to run for 5
seconds, and the comfort air blower will continue to run for
two minutes.
3.2
BASIC OPERATION – COOLING CYCLE
On a call for cool the compressor and condenser fan will
start immediately, and the comfort air blower will start 6
seconds later on cooling (high) speed. When the thermostat
is satisfied the compressor and condenser fan will stop, and
the comfort air blower will continue to operate for 60
seconds.
3.2.1 COMPRESSOR LOCKOUT (CANADIAN
UNITS ONLY)
The units built for Canadian use are equipped with high and
low pressure controls. These controls protect the
compressor from extreme conditions such as high refrigerant
pressure or a loss of charge. When this happens the
compressor is held off line by a lock out relay. To reset the
lock out relay, the thermostat must be set to the “OFF”
position and then returned to the normal operating position.
The compressor is now allowed to function. If the
compressor continues to lock out, service personnel should
be called to check the unit.
3.3
MANUAL FAN (CONTINUOUS AIRFLOW)
OPERATION
If wall thermostat is set to MANUAL (ON) position to
operate comfort air blower continuously to provide air
circulation throughout the building, the blower will
operate on the heating speed rather than the cooling as is
typical with most systems. This permits the air to
circulate as desired but helps keep the operating noise
level down as well as conserving energy.
During a call for cooling, the blower automatically shifts up
to cooling speed, and remains there until 60 seconds
after thermostat is satisfied then drops back to heating
speed.
SECTION 3 • UNDERSTANDING HOW
YOUR FURNACE WORKS
Your installer should have given you a detailed explanation
of how the furnace operates. Shown below are the basic
operation characteristics and sequence of operation. If you
have any questions consult your installer and/or service
agency.
This furnace is equipped with a vent shut-off system which
monitors the combustion air into the burners by means of a
pressure sensing device. When the vent becomes blocked,
this device turns off the gas valve circuit to prevent flue
products from entering the structure. In the event that this
occurs, shut off furnace and contact a qualified service
agency.
2.3. ALTERATION OF FURNACE CONTROLS
WARNING
Never store anything combustible near or on
your furnace. These include brooms,
dustmops, vacuum cleaners, other cleaning
tools or items, plastic or plaxtic containers,
paper bags or other paper products. A fire
could occur resulting in damage, injury or
death.
WARNING
Do not alter any gas or electrical controls (gas
control, pilot or safety controls) in any manner.
Altering them could cause furnace to operate
unsafely resulting in damage, injury or death.
There are many types of thermostats
compatible with this furnace. Make sure you
understand the specific type installed. Ask
installer for detailed explanation, and retain
thermostat instruction manual for reference.
* * IMPORTANT * *
