Advertisement
HOW YOUR GAS FURNACE WORKS
Your furnace is a very easy appliance to take for granted. Season after
season, it sits there in your home, keeping you warm and comfortable.
For this reason, you may never have given much thought to the way
your furnace operates. In order to get the safest and most efficient oper-
ation from your furnace, you should understand
its job.
When you set your thermostat to provide more heat in your home, you
are starting the heating cycle of the furnace.
starts to purge the heat exchanger
hot surface ignitor glows and after a warm-up
opens and ignition occurs. A short time later, the blower starts and dis-
tributes the warm air throughout
ting on your thermostat
is reached,
burners are turned off, and the blower continues to run until the remain-
ing warm air in the system is distributed.
heating cycle has ended.
1.
This appliance does not have a pilot. It is equipped with an ignition
device which automatically
burner by hand.
2.
BEFORE
OPERATING;
smell all around the appliance
gas. Be sure to smell next to the floor because
heavier than air and will settle on the floor.
3.
Use only your hand to push the gas control switch to the "on" posi-
tion. Never use tools. If the switch will not operate by hand, don't
try to repair
it, call a qualified
attempted repair may result in a fire or explosion.
4.
Do not use this appliance if any part has been under water. Imme-
diately call a qualified service technician
and to replace any part of the control system and any gas control,
which has been under water.
OPERATING INSTRUCTIONS
1.
STOP! Read the safety information
2.
Set the thermostat to the lowest setting in the heat mode.
3.
Turn off all electric power to the appliance.
4.
Remove furnace burner access panel/door.
5.
Move gas control switch to the "OFF" position. Do not force. See
Figure 3.
6.
Wait five (5) minutes to clear out any gas. If you then smell gas,
STOP! Follow "B" in the safety information
smell gas, go to next step.
To Gas
Supply
Ground
Union
Configuration
FIGURE 4: Upflow/Downflow
Gas Piping
Johnson Controls Unitary Products
how your furnace does
First, the inducer motor
of any remaining
gases. Next, the
period the gas valve
the home. When the temperature
the gas valve closes, the main
When the blower stops, the
lights the burner. Do not try to light the
area for
some gas is
service
technician.
Force
to inspect the appliance
above for your protection.
above.
If you don't
To Gas
Supply
Ground
Union
Gas
Valve
Gas
Pipe
Upflow
7.
Move gas control switch to the "ON" position. Do not force. See
Figure 3.
8.
Replace furnace burner access panel/door.
9.
Tum on all electric power to the appliance.
10.
Set thermostat
to the desired setting. Burner will light, which may
take 30-60 seconds.
11.
After three (3) trials for ignition, if the appliance will not operate fol-
low the instructions,
your service technician or gas supplier.
TO TURN OFF THE APPLIANCE
1.
Set the thermostat to lowest setting in heating mode.
set-
2.
Tum off all electric power to the appliance
formed.
3.
Remove furnace burner access panel/door.
4.
Move gas control switch to the "OFF" position. See Figure 3.
5.
Replace furnace burner access panel/door.
LAWARNING!
Should overheating occur, or the gas valve fail to shut off,
turn the external manual gas valve in the gas supply line to
the furnace to the "off" position and let the furnace cool off
before shutting off the electrical power supply.
or
OUTLET
PRESSURE
PORT
INLET --.
WRENCH
BOSS
/
INLET/
PRESSURE
PORT
FIGURE 3: Single Stage Gas Valve
Ground
Union
Gas
Pipe
Downflow
Configuration
420706-UUM-A-1008
"TO TURN OFF THE APPLIANCE"
if service is to be per-
VENT PORT
ON/OFF SWITCH
(Shown in ON position)
Ground
Union
Gas
Valve
and call
3
Advertisement
