Circulating Air Filters - Goodman GSM Installation & Operating Instructions Manual

BLOWER DOOR INTERLOCK SWITCH
The purpose of the switch is to disconnect electrical power to the furnace should the blower door
become dislodged, removed, or not properly reinstalled such as when performing a filter change.
ALLOWING THE FURNACE TO OPERATE WITHOUT THE BLOWER DOOR BEING SECURELY IN
PLACE CAN CAUSE COMBUSTION PRODUCTS TO BECOME CIRCULATED THROUGHOUT
THE LIVING AREA WHICH CAN CAUSE SERIOUS ILLNESS OR CARBON MONOXIDE
POISONING. To test the operation of this switch, place the furnace in operation and remove the
blower access door. The burner flames will extinguish and the venter and circulating air blowers
should both stop. To restore the unit to normal operation, shut off the electrical power to the unit,
replace the blower access door and restore the electrical power.
STACK OVER-TEMPERATURE SWITCH
Located on the venter blower housing, this switch is designed to shut down the burners should the
circulating air blower fail or the secondary coil become blocked. To test this switch, bypass the main
limit switch, disconnect the circulating air blower, and place the furnace in operation. After a short
period of time this switch should function shutting down the burners. IT IS VERY
IMPORTANT TO REMOVE THE BYPASS FROM THE MAIN LIMIT SWITCH AND REPLACE THE
WIRES WHICH WERE DISCONNECTED FOR THIS TEST prior to returning the furnace in normal
operation.
INTEGRATED FAN / IGNITION CONTROL
This furnace is equipped with a combination ignition module and fan control. The ignition source is a
hot surface igniter. This device ignites the burners upon a call for heat. It also controls the venter
blower and the various speed selections of the circulating air blower. This control is located in the
circulating air blower compartment.
Upon a demand for heat the venter is energized. After a short purge, the hot surface igniter is
energized. The burners are ignited after a (17) second delay and are proven by the flame sensor.
The circulating air blower is energized approximately thirty (30) seconds after the burners are ignited.
The circulating air blower is de-energized approximately two and one half (2 1/2) minutes after the
burners are extinguished.
THIS CONTROL IS NOT FIELD ADJUSTABLE OR SERVICEABLE.

CIRCULATING AIR FILTERS

One of the most common causes of problems in a forced air heating system is blocked or dirty filters.
Circulating air filters must be inspected monthly for dirt accumulation and replaced if necessary.
Failure to maintain clean filters can cause premature heat exchanger failure.
A new home may require more frequent replacement until all construction dust and dirt is removed.
Circulating air filters are to be installed in the return air duct, external to the furnace cabinet.
CAUTION
Before performing any service on this furnace, including checking or replacing circulating air filters -
disconnect main power.
DO NOT operate the furnace for extended periods of time without filters in place. Dust and dirt in the
air will restrict the air movement over the secondary coil causing nuisance cycling of the safety
controls and cause a no heat condition
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