When the room thermostat is satisfied, the electrical circuit to the gas valve is opened, closing off both main burner and pilot gas simultaneously. If the pilot burner should fail to light, contact your heating contractor or gas utility for service to insure that proper operating conditions are restored.
INPUT
The correct heat capacity of the furnace is regulated by the burner orifices and the gas pressure. The proper orifices are furnished but the gas pressure regulator must be adjusted by the installer or gas utility service technician.
OPERATING INSTRUCTIONS
TO SHUT DOWN THE FURNACE:
1.Close the main gas shutoff valve(s).
2.Turn off the electric power supply.
TO LIGHT THE FURNACE:
1.Do not attempt to light manually.
2.Open the main gas shutoff valve(s).
3.Adjust the set point of the room thermostat above the temperature in the space.
4.Turn on the electric power supply.
5.The draft fan will operate. After an adequate purge time, the electric spark igniter will light the burners.
6.The burners will extinguish and relight automatically upon the demand of the room thermostat.
FIGURE 2: TYPICAL INSTALLATION
VENT SAFETY SYSTEM:
This gas furnace is equipped with an automatic reset high temperature sensor or rollout switch which in the unlikely event of a sustained main burner flame rollout will shut off the flow of gas by closing the main gas valve. The ignition modules will also be disabled, pre- venting the flow of gas to the valves. The switch is located inside the gas heat access panel above the burner inlet. Flame rollout can be caused by blockage of the power vent system, improper gas pressure or adjustment. If this event occurs the furnace will not operate properly, gas supply to the furnace should be shut off and no attempt should be made to place the furnace in operation. The system should be inspected by a qualified service technician. Refer to Figure 2 for a typical installation.
100% SHUT OFF:
The ignition modules are designed for 100%
A.Turning the system switch on the room thermostat
to the “OFF” position and back to the “HEAT” posi- tion.
B.Decreasing the set point of the room thermostat below the temperature in the conditioned space and returning it to its original setting.
C.Opening and closing the unit's main disconnect switch.
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