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A media air filter or electronic air cleaner can be used as an
alternate filter. Follow the filter sizes given in the Recommended
Minimum Filter Size chart to ensure proper unit performance.
To remove filters from an external filter rack in an upright upflow
installation, follow the directions provided with external filter rack
kit.
Horizontal Unit Filter Removal
Filters in horizontal installations are located in the central return
register or the ductwork near the furnace.
To remove:
1. Turn off electrical power to the furnace.
2. Remove the filter(s) from the central return register or
ductwork.
3. Replace the filter(s) by reversing the procedure for removal.
4. Turn on electrical power to the furnace.
Media Air Filter or Electronic Air Cleaner Removal
Follow the manufacturer’s directions for service.
Burners
Visually inspect the burner flames periodically during the heating
season. Turn on the furnace at the thermostat and allow several
minutes for flames to stabilize, since any dislodged dust will alter
the flames normal appearance.
Flames should be stable, quiet, soft and blue (dust may cause
orange tips but they must not be yellow). They should extend
directly outward from the burners without curling, floating or
lifting off. Flames must not impinge on the sides of the heat
exchanger firing tubes.
Induced Draft and Circulator Blowers
The bearings in the induced draft blower and circulator blower
motors are permanently lubricated by the manufacturer. No
further lubrication is required. Check motor windings for
accumulation of dust which may cause overheating. Clean as
necessary.
Condensate Trap and Drain System
(Qualified Servicer Only)
Annually inspect the drain tubes, drain trap and field-supplied
drain line for proper condensate drainage. Check drain system
for hose connection tightness, blockage and leaks. Clean or
repair as necessary.
Flame Sensor (Qualified Servicer Only)
Under some conditions, the fuel or air supply can create a nearly
invisible coating on the flame sensor. This coating acts as an
insulator causing a drop in the flame sense signal. If the flame
sense signal drops too low, the furnace will not sense flame and
will lock out. The flame sensor should be carefully cleaned by a
qualified servicer using emery cloth or steel wool. Following
cleaning, the flame sense signal should be 1 to 6 microamps at
115 volts.
Igniter (Qualified Servicer Only)
If the igniter and the surrounding air are at about 70°F (21ºC) and
the igniter wires are not connected to any other electrical
components, the resistance of the igniter should not exceed
75 ohms. If the resistance does exceed 75 ohms, the igniter
should be replaced.
Flue Passages (Qualified Servicer Only)
The heat exchanger flue passageways should be inspected at the
beginning of each heating season. If necessary, clean the
passageways as outlined below.
1. Turn off the electrical power and gas supply to the furnace.
2. Disconnect the gas line and remove the burner/manifold
assembly by removing the screws securing the assembly to
the partition panel.
3. Disconnect the flue pipe system from the induced draft
blower.
4. Remove the induced draft blower and, drain and pressure tap
hoses from the recuperator coil front cover.
5. Remove the recuperator coil front cover to expose the coil
tubes and turbulators.
6. Remove the recuperator coil turbulators individually by slowly
pulling each turbulator forward firmly.
7. Clean the recuperator coil tubes using a long handle wire
brush, such as a gun cleaning brush.
8. Clean the primary heat exchanger tubes using a wire brush
attached to a length of high grade stainless steel cable, such
as drain cleanout cable. Attach a variable speed reversible
drill to the other end of the cable. Slowly rotate the cable with
the drill and insert it into one of the heat exchanger tubes.
While reversing the drill, work the cable in and out several
times to obtain sufficient cleaning. Repeat for each tube.
9. Clean the residue from the furnace by using a vacuum
cleaner.
10. Replace the parts removed in the previous steps in reverse
order.
11. Turn on electrical power and gas to furnace. Check for leaks
and proper unit operation.
12. Severe heat exchanger fouling is an indication of an
operational problem. Perform the checks listed in “Start-Up
Procedure and Adjustments” to reduce the chances of
repeated fouling.
Goodman 96
To avoid personal injury or death due to electrical shock,
do not remove any internal compartment covers or
attempt any adjustment. Contact a qualified servicer at
once if an abnormal flame should develop.
WARNING