66
SSCBL-RPBL-IOM (10-22) 149159-C
SETSCREW ON FRONT OF SWITCH
MUST BE MANUALLY ADJUSTED
WHILE UNIT IS OPERATING
NEGATIVE PRESSURE CONNECTION
ON FRONT OR TOP OF SWITCH
SENSES BLOWER SIDE OF FILTERS
POSITIVE PRESSURE CONNECTION
ON BACK OR BOTTOM OF SWITCH
SENSES AIR INLET SIDE OF FILTERS
ADJUSTMENTS—CONTINUED
Dirty Filter Switch Adjustment—Continued
Figure 46. Dirty Filter Switch
Burner Air Shutter Adjustment
⚠ DANGER ⚠
Failure to adjust air shutters according to directions could cause property damage, personal injury,
and/or death.
NOTES:
• A limited amount of yellow-tipping is permissible for liquefied petroleum gases. Natural gas
should not display any yellow-tipping.
• When making the adjustment, close the air shutters no more than is necessary to eliminate the
problem condition.
•
Air shutters are required on propane gas units but are optional on natural gas units . A slotted burner air adjustment
screw on the end manifold bracket (see
) moves the air shutters and adjusts all burners simultaneously .
Turn the adjustment screw clockwise to open the air shutter or counterclockwise to close the air shutter .
•
After the furnace has been in operation for 15 minutes, close the air shutter until the flame turns yellow . Open the
shutter until yellow disappears .
Figure 47. Burner Air Shutter Adjustment Screw
Burner Air
Shutter
Adjustment
Screw
