Integrated Control DIP Switch Settings − Conventional Thermostat (non−communi- cating)
SL280UHV units are equipped with a two−stage, variable speed 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 jumpers. The control includes an internal watchguard feature which automatically resets the ignition control when it has been locked out. After one hour of con- tinuous thermostat demand for heat, the watchguard will break and remake thermostat demand to the furnace and automatically reset the control to relight the furnace.
Note: All icomfortt settings are set at the icomfort Touch® thermostat. See icomfortt installation instruction. In icom- fortt communication system all DIP switch and clippable link settings are ignored. For conventional thermostats pro- ceed with DIP switch and clippable link settings as outlined in the following.
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.
Select " for two−stage heating operation con- trolled by a two−stage heating thermostat (factory set- ting);
b − Select " 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.
Switches 3 and 4 −− 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 seconds. The blower off delay affects comfort and is adjustable to satisfy individ- ual 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 temperatures; shorter set- tings provide higher supply air temperatures.Table 12 pro- vides the blower off timings that will result from different switch settings.
TABLE 12
Blower Off Delay Switch Settings
Blower Off Delay | Switch 3 | Switch 4 | |
(Seconds) | |||
|
| ||
60 | On | Off | |
90 (Factory) | Off | Off | |
120 | Off | On | |
180 | On | On |
Indoor Blower Operation DIP Switch Settings Switches 5 and 6 −− Cooling Mode Blower Speed −− The unit is shipped from the factory with the dip switches posi- tioned for high speed (4) indoor blower motor operation during the cooling mode. Table 13 provides the cooling mode blower speeds that will result from different switch settings. Switches 5 and 6 set the blower cfm for second− stage cool. The integrated control automatically ramps down to 70% of the second−stage cfm for first−stage cfm. Refer to tables for corresponding cfm values.
TABLE 13
Cooling Mode Blower Speeds
Speed | Switch 5 | Switch 6 |
Low | On | On |
Medium Low | Off | On |
Medium High | On | Off |
High (Factory) | Off | Off |
Switches 7 and 8 −− Cooling Blower Speed Adjustment
−−The unit is shipped from the factory with the dip switches positioned for NORMAL (no) adjustment. The dip switches may be positioned to adjust the blower speed by +10% or −10% to better suit the application. Table 14 below provides blower speed adjustments that will result from different switch settings. Refer to tables for corresponding cfm val- ues.
TABLE 14
Cooling Blower Speed Adjustment
Adjustment | Switch 7 | Switch 8 |
+10% (approx.) | On | Off |
Factory Default | Off | Off |
−10% (approx.) | Off | On |
Switches 9 and 10 −− Cooling Mode Blower Speed Ramping −− Blower speed ramping may be used to en- hance dehumidification performance. The switches are factory set at option A which has the greatest effect on de− humidification performance. Table 15 provides the cooling mode blower speed ramping options that will result from different switch settings. The cooling mode blower speed ramping options are detailed on the next page.
NOTE − The off portion of the selected ramp profile also ap- plies during heat pump operation in dual fuel applications.
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