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Bryant Heating and Cooling System Gas Furnace 986T Maintenance

The Bryant Heating and Cooling System Gas Furnace 986T Maintenance is a quick step by step procedure that ensures the quality performance of your machine. Remove risks by following the safety precautions in the form.
MaintainX
04/26/2021

Bryant Heating and Cooling System Gas Furnace 986T Maintenance

The Bryant Heating and Cooling System Gas Furnace 986T Maintenance is a quick step by step procedure that ensures the quality performance of your machine. Remove risks by following the safety precautions in the form.

    WARNING: FIRE OR EXPLOSION HAZARD Failure to follow this warning could result in personal injury, death and/or property damage. Never store flammable or combustible materials on, near, or in contact with the furnace, such as:

    Spray or aerosol cans, rags, brooms, dust mops, vacuum cleaners, or other cleaning tools.

    Soap powders, bleaches, waxes or other cleaning compounds, plastic or plastic containers, gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids, or other volatile fluids.

    Paint thinners and other painting compounds, paper bags, or other paper products. Exposure to these materials could lead to corrosion of the heat exchangers.

    WARNING: ELECTRICAL SHOCK AND FIRE HAZARD Failure to follow this warning could result in personal injury, death, and/or property damage. Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or s

    WARNING: CARBON MONOXIDE POISONING AND FIRE HAZARD Failure to follow this warning could result in personal injury, death and/or property damage. Never operate furnace without a filter or filtration device installed. Never operate a furnace with filter or

    CAUTION: CUT HAZARD Failure to follow this caution may result in personal injury. Sheet metal parts may have sharp edges or burrs. Use care and wear appropriate protective clothing, safety glasses and gloves when handling parts, and servicing furnaces.

    The minimum maintenance on this furnace is as follows:

    Cleaning and/or Replacing Air Filter

    The air filter type may vary depending on the application or orientation. The filter is external to the furnace casing. There are no provisions for an internal filter with this furnace. See “Filter Arrangement” under the “Installation” section of this man

    WARNING: CARBON MONOXIDE POISONING AND FIRE HAZARD Failure to follow this warning could result in personal injury, death and/or property damage. Never operate furnace without a filter or filtration device installed. Never operate a furnace with filter or

    NOTE: If the filter has an airflow direction arrow, the arrow must point toward the blower. To clean or replace filters, proceed as follows:

    WARNING: ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD Failure to follow this warning could result in personal injury or death, or property damage. Before installing, modifying, or servicing system, main electrical disconnect switch must be in the OFF positi

    Blower Motor and Wheel Maintenance

    The inducer and blower motors are pre--lubricated and require no additional lubrication. These motors can be identified by the absence of oil ports on each end of the motor.

    The following items should be performed by a qualified service technician. Clean blower motor and wheel as follows:

    Disconnect the vent and combustion air pipe by:

    See Fig. 60 For Steps 5 through 14.

    NOTE: Blower wheel is fragile. Use care

    If greasy residue is present on blower wheel, remove wheel from the blower housing and wash it with an appropriate degreaser. To remove wheel:

    NOTE: Mark blower mounting arms and blower housing so each arm is positioned at the same hole location during reassembly.

    NOTE: Be sure to attach ground wire and reconnect blower harness plugs to blower motor.

    WARNING: ELECTRICAL OPERATION HAZARD Failure to follow this warning could result in personal injury or death. Blower door switch opens 115--v power to control. No component operation can occur unless switch is closed. Caution must be taken when manually c

    Downflow or horizontal furnaces with vent pipe through furnace only:

    Turn on electrical supply. If outdoor temperature is below 70_F, turn off circuit breaker to outdoor unit before running furnace in the cooling cycle. Turn outdoor circuit breaker on after completing cooling cycle. (See Fig. 34.) Manually close blower doo

    NOTE: If R--W/W1 thermostat terminals are jumpered at the time blower door switch is closed, blower will run for 90 sec before beginning a heating cycle.

    Cleaning Burners and Flame Sensor

    The following items must be performed by a qualified service technician. If the burners develop an accumulation of light dirt or dust, they may be cleaned by using the following procedure:

    NOTE: Use a back-up wrench on the gas valve to prevent the valve from rotating on the manifold or damaging the mounting to the burner assembly.

    WARNING:ELECTRICAL SHOCK AND FIRE HAZARD Failure to follow this warning could result in personal injury, death, and/or property damage. Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or se

    Refer to Fig. 61.

    To reinstall burner assembly:

    NOTE: If manifold does not fit flush against the burner, do not force the manifold on the burner assembly. The burners are not fully seated forward in the burner assembly. Remove the manifold and check burner positioning in the burner assembly assembly be

    NOTE: Use propane-resistant pipe dope to prevent leaks. Do not use Teflon tape.

    WARNING:FIRE OR EXPLOSION HAZARD Failure to follow this warning could result in personal injury, death, and/or property damage. Never purge a gas line into a combustion chamber. Never test for gas leaks with an open flame. Use a commercially available soa

    Servicing Hot Surface Igniter

    The igniter does NOT require annual inspection. Check igniter resistance before removal. Refer to Fig. 55, 56 and 61.

    Remove igniter assembly.

    Flushing Collector Box and Drainage System

    WARNING: ELECTRICAL SHOCK AND FIRE HAZARD Failure to follow this warning could result in personal injury, death, and/or property damage. Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or s

    NOTE: Ensure the pressure switch tube disconnected from the pressure switch is higher than the collector box opening or water will flow out of tube

    NOTE: Do NOT blow into tube with tube connected to the pressure switch.

    Cleaning Condensate Drain and Trap

    NOTE: If the condensate trap is removed, a new gasket between the trap and collector box is required. Verify a condensate trap gasket is included in the service kit or obtain one from your local distributor

    NOTE: If condensate has a heat pad attached to the trap, trace the wires for the pad back to the connection point and disconnect the wires for the heat pad.

    To re-install Condensate Drain and Trap:

    Checking Heat Pad Operation (If Applicable)

    NOTE: The Heat Pad, when used, should be wrapped around the condensate drain trap. There is no need to use heat tape within the furnace casing. Most heat tapes are temperature activated, and it is not practical to verify the actual heating of the tape. Ch

    Check for signs of physical damage to heat tape such as

    Cleaning Heat Exchangers

    Primary Heat Exchangers

    If the heat exchangers get an accumulation of light dirt or dust on the inside, they may be cleaned by the following procedure:

    NOTE: If the heat exchangers get a heavy accumulation of soot and carbon, both the primary and secondary heat exchangers should be replaced rather than trying to clean them thoroughly due to their intricate design. A build--up of soot and carbon indicates

    WARNING: ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD Failure to follow this warning could result in personal injury or death, or property damage. Before installing, modifying, or servicing system, main electrical disconnect switch must be in the OFF positi

    WARNING:ELECTRICAL SHOCK AND FIRE HAZARD Failure to follow this warning could result in personal injury, death, and/or property damage. Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or se

    Disconnect wires or connectors to

    NOTE: Burner cover, manifold, gas valve, and burner assembly should be removed as one assembly.

    NOTE: After cleaning, inspect the heat exchangers to ensure they are free of all foreign objects that may restrict flow of combustion products.

    Refer to furnace wiring diagram and reconnect wires to

    WARNING:FIRE OR EXPLOSION HAZARD Failure to follow this warning could result in personal injury, death, and/or property damage. Never purge a gas line into a combustion chamber. Never test for gas leaks with an open flame. Use a commercially available soa

    Secondary Heat Exchangers

    Wiring Diagrams

    WINTERIZATION

    CAUTION: UNIT AND PROPERTY DAMAGE HAZARD Failure to follow this caution may result in unit component or property damage. If the furnace is installed in an unconditioned space where the ambient temperatures may be 32_ F (0_ C) or lower, freeze protection m

    CAUTION:UNIT COMPONENT DAMAGE HAZARD Failure to follow this caution may result in damage to the furnace and other property damage. Do not use ethylene glycol (automotive antifreeze coolant or equivalent). Failure of plastic components may occur.

    Fig. 55 -- Igniter Position -- Top View

    Fig. 56 -- Igniter Position -- Side View

    Fig. 57 -- Priming Condensate Trap (Appearance May Vary)

    Fig. 58 -- Cleaning Heat Exchanger Cell

    Fig. 59 -- Burner Flame

Source: Bryant

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