Installer’s Guide
R On/Off Switch |
LIGHTING INSTRUCTIONS
▲! WARNING
DO NOT attempt to manually light the burner.
Failure to follow this warning could result in property damage, personal injury or death.
Lighting instructions appear on each unit. Each instal- lation must be checked out at the time of initial start up to insure proper operation of all components. Check out should include putting the unit through one complete cycle as outlined below.
Turn on the main electrical supply and set the thermo- stat above the indicated temperature. The ignitor will automatically heat, then the gas valve is energized to permit the flow of gas to the burners. After ignition and flame is established, the flame control module monitors the flame and supplies power to the gas valve until the thermostat is satisfied.
To shut off.
For complete
▲! CAUTION
If this is done during the cold weather months, provi- sions must be taken to prevent
Failure to follow this warning could result in property damage.
Whenever your house is to be vacant, arrange to have someone inspect your house for proper temperature. This is very important during freezing weather. If for any reason your furnace should fail to operate damage could result, such as frozen water pipes.
SEQUENCE OF OPERATION
Thermostat call for heat
R and W thermostat contacts close signaling the control module to run its
As the induced draft blower comes up to speed, the pressure switch contacts will close and the ignitor warm up period will begin. The ignitor will heat for approxi- mately 20 seconds, then the gas valve is energized to permit gas flow to the burners. The flame sensor con- firms that ignition has been achieved.
After the flame sensor confirms within a 4 second trial period that ignition has been achieved, the delay to fan ON period begins timing. After approximately 45 sec- onds the indoor blower motor will be energized and con- tinue to run during the heating cycle.
When the thermostat is satisfied, R and W thermostat contacts open, the gas valve will close, the flames will extinguish, and the induced draft blower will be
CONTROL AND SAFETY SWITCH ADJUSTMENTS LIMIT SWITCH CHECK OUT
The limit switch is a safety device designed to close the gas valve should the furnace become overheated. Since proper operation of this switch is important to the safety of the unit, it must be checked out on initial
start up by the installer.
To check for proper operation of the limit switches, set the thermostat to a temperature higher than the indi- cated temperature to bring on the gas valve. Restrict the airflow by blocking the return air (disconnecting the indoor blower may trip the inducer limit). When the furnace reaches the maximum outlet temperature as shown on the rating plate, the burners must shut off. If they do not shut off after a reasonable time and over- heating is evident, a faulty limit switch is probable and the limit switch must be replaced. After checking the operation of the limit control, be sure to remove the pa- per or cardboard from the return air inlet. Refer to Ser- vice Facts for additional instructions.
NOTE TO INSTALLER
Review the following warnings with the owner. Review contents of USER’S INFORMATION MANUAL with the owner.
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