Lennox International Inc Comprehensive Guide to Lennox DIP Switch Settings for Enhanced Furnace Performance

Integrated Control DIP Switch Settings

EL296UHE units are equipped with a two-stage integrated control. This control manages ignition timing, heating mode fan off delays and indoor blower speeds based on selections made using the control dip switches and jump­ ers. The control includes an internal watchguard feature which automatically resets the ignition control when it has been locked out. After one hour of continuous thermostat demand for heat, the watchguard will break and remake thermostat demand to the furnace and automatically reset the control to relight the furnace.

Heating Operation DIP Switch Settings

Switch 1 -- Thermostat Selection -- This unit may be

used with either a single-stage or two-stage thermostat. The thermostat selection is made using a DIP switch which must be properly positioned for the particular application. The DIP switch is factory-positioned for use with a two- stage thermostat. If a single-stage thermostat is to be used, the DIP switch must be repositioned.

a- Select “OFF” for two-stage heating operation con­ trolled by a two-stage heating thermostat (factory set­ ting);

b - Select “ON” for two-stage heating operation con­ trolled by a single-stage heating thermostat. This set­ ting provides a timed delay before second-stage heat is initiated.

Switch 2 -- Second Stage Delay (Used with Single- Stage Thermostat Only) -- This switch is used to deter­ mine the second stage on delay when a single-stage ther­ mostat is being used. The switch is factory-set in the OFF position, which provides a 7-minute delay before second- stage heat is initiated. If the switch is toggled to the ON position, it will provide a 12-minute delay before second- stage heat is initiated. This switch is only activated when the thermostat selector jumper is positioned for SINGLE- stage thermostat use.

Indoor Blower Operation DIP Switch Settings Switches 3 and 4 -- Heating Mode Blower-Off Delay --

The blower-on delay of 30 seconds is not adjustable. The blower-off delay (time that the blower operates after the heating demand has been satisfied) can be adjusted by moving switches 3 and 4 on the integrated control. The unit

is shipped from the factory with a blower-off delay of 90 se­ conds. The blower off delay affects comfort and is adjust­ able to satisfy individual applications. Adjust the blower off delay to achieve a supply air temperature between 90° and 110°F at the exact moment that the blower is de-energized. Longer off delay settings provide lower supply air tempera­ tures; shorter settings provide higher supply air temperatu­ res.Table 11 provides the blower off timings that will result from different switch settings.

TABLE 11

Blower Off Heating Mode Delay Switch Settings

Blower Off Delay	Switch 3	Switch 4
(Seconds)
60	On	Off
90 (Factory)	Off	Off
120	Off	On
180	On	On

Switch 5 -- Cooling Mode Blower-Off Delay-- The unit is shipped from the factory with the dip switch positioned OFF for a 45 second delay. Table 12 provides the cooling mode off delay settings.

TABLE 12

Blower Off Cooling Mode Delay Switch Settings

Blower Off Delay	Switch 5
(Seconds)
45 (Factory)	Off
2	On

Switches 6 and 7 -- Continuous Fan Mode -- Continuous fan speed can be controlled by changing DIP switch posi­ tions. Table 13 below provides DIP switch settings for con­ tinuous fan mode.

TABLE 13

Continuous Fan Mode Settings

Continuous Fan	Switch 6	Switch 7
Mode
Low Heat Speed	Off	Off
(factory)
Low Cool Speed	Off	On
High High Speed	On	Off
High Cool Speed	On	On

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