This furnace is equipped with a multi-speed circulator blower. This blower provides ease in adjusting blower speeds. The Specifica-
tion Sheet applicable to your model provides an airflow table, showing the relationship between airflow (CFM) and external static
pressure (E.S.P .), for the proper selection of heating and cooling
1. Determine the tonnage of the cooling system installed with
the furnace. If the cooling capacity is in BTU/hr divide it by
12,000 to convert capacity to tons.
Example: Cooling Capacity of 30,000 BTU/hr.
30,000/12,000 = 2.5 Tons
2. Determine the proper air flow for the cooling system. Most
cooling systems are designed to work with air volume between 350 and 450 CFM per ton. Most manufacturers recommend an
air flow of about 400 CFM per ton.
Example: 2.5 tons X 400 CFM per ton = 1000 CFM
3. Select the heating speed for your model from the heating speed chart in the Specification Sheet. The selected speed must
provide a temperature rise within the rise range listed with the particular model.
To adjust the circulator blower speed, proceed as follows:
1. Turn OFF power to the furnace.
2. Select the heating and cooling blower speeds that match the installation requirements from the airflow table in the
3. Relocate desired motor leads to the circulator blower heat and cool speed terminals on the integrated control module.
(Terminals are identified as HEAT and COOL). If heating and cooling blower speeds are the same, a jumper wire must
be used between the heat and cool terminals.
4. Connect all unused blower motor leads to the "PARK" terminals on the integrated control module. Any leads not
connected to the "PARK" terminals must be taped.
5. Turn ON power to furnace.
6. Verify proper temperature rise as outlined in the Temperature Rise section of Startup Procedure and Adjustment.
In general lower heating speeds will: reduce electrical consumption, lower operating sound levels of the blower, and increase the outlet
air temperature delivered to the home. The speeds available allow the blower performance to be optimized for the particular
The integrated control module on 96% models provides a selectable heat off delay function. The heat off delay period may be set to
100 or 150 seconds by cutting the jumper on the control module. The delay is factory shipped at 150 seconds but may be changed
to suit the installation requirements and/or homeowner preference.
The integrated control board on 92% models has a fixed blower off delay of 150 seconds.
The normal power up sequence is as follows:
115 VAC power applied to furnace.
Integrated control module performs internal checks.
LED will flash once at power up then remain on.
Integrated control module monitors safety circuits continuously.
Furnace awaits call from thermostat.
The normal operational sequence in heating mode is as follows:
R and W thermostat contacts close, initiating a call for heat.
Integrated control module performs safety circuit checks.
Induced draft blower is energized for a 15-second prepurge.
Pressure switch contacts are closed.
O AVOID PERSONAL INJURY OR DEATH DUE TO ELECTRICAL SHOCK
POWER TO THE FURNACE BEFORE CHANGING SPEED TAPS