Bryant 577D----A Indoor Fan Motor Troubleshooting, Furnace Control Troubleshooting

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emergency heating or cooling operation using a common thermostat and the terminal strip connections on the two control boards (See Non-Communicating Emergency Cooling/Heating Mode) and will display Status Code 16, System Communication Fault, on amber STATUS LED. No further troubleshooting information will be available at UI until communications are re-established.

If either COMM LED does not light within proper time period and status codes are not displayed;

1.Check system transformer high- and low-voltage to be sure the system is powered.

2.Check ABCD connection on both boards.

3.Check fuse on furnace board to be sure it is not blown. If fuse is open, check system wiring before replacing it to be sure a short does not cause a failure of replacement fuse.

If COMM LED does not light within proper time period and status code is displayed:

1.Check system wiring to be sure UI is powered and connections are made A to A, B to B, etc. and wiring is not shorted. Miswiring or shorting of the ABCD communications wiring will not allow successful communications.

NOTE: Shorting or miswiring low-voltage system wiring will not cause damage to unit control or UI but may cause low voltage fuse to open.

C. Indoor Fan Motor Troubleshooting

The indoor fan is driven by an ECM motor consisting of two parts: the control module and the motor winding section. Do not assume motor or module is defective if it will not start. Use the designed-in LED information aids and follow troubleshooting steps described below before replacing motor control module or entire motor. Motor control module is available as a replacement part.

VERIFY MOTOR WINDING SECTION

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

After disconnecting power from the ECM motor, wait at least 5 minutes before removing the control section. Internal capacitors require time to discharge.

Before proceeding to replace a motor control module:

1.Check motor winding section to be sure it is functional.

2.Remove motor control module section and unplug winding plug. Motor shaft should turn freely, resistance between any two motor leads should be similar and resistance between any motor lead and unpainted motor end should exceed 100,000 ohms.

3.Failing any of these tests, entire ECM motor must be replaced.

4.Passing all of the tests, motor control module alone can be replaced.

MOTOR TURNS SLOWLY

1.Low static pressure loading of blower while access panel is removed will cause blower to run slowly. Particularly at low airflow requests. This is normal, do not assume a fault exists.

2.Recheck airflow and system static pressure using UI service screens with access panel in place.

NOTE: Blower motor faults will not cause a lockout of blower operation. The fan coil control will attempt to run the blower motor as long as UI maintains a demand for airflow. The control will not

operate electric heaters while a fault condition exists. The control communicates with the motor at least once every five seconds, even when the motor is idle. If, during operation, the control does not communicate with the motor for more than 25 seconds, the motor will shut itself down and wait for communications to be reestablished.

D. Furnace Control Troubleshooting

Furnace control faults indicated by flashing codes on the amber system STATUS LED can be resolved using troubleshooting information provided below. Codes are listed in order of their priority, highest to lowest. Though multiple faults can exist at any time, only the highest priority code will be displayed on STATUS LED. Clearing the indicated fault when multiple faults exist will cause the next highest priority Status Code to be flashed. All existing faults, as well as a fault history, can be viewed at UI.

STATUS CODE CONTINUOUS OFF

Check for 230 VAC at L1 and L2, and 24 VAC at SEC-1 and SEC-2.

STATUS CODE CONTINUOUS ON Control has 24 VAC power.

STATUS CODE 11 - NO PREVIOUS CODE

Stored status codes are erased automatically after 72 hours.

STATUS CODE 12 - BLOWER ON AFTER POWER UP

(230 VAC or 24 VAC) Blower runs for 90 seconds if unit is powered up during a call for heat (R-W/W1 closed) or (R-W/W1 opens) during blower on-delay period.

STATUS CODE 13 - LIMIT CIRCUIT LOCKOUT

Lockout occurs if a limit or flame rollout switch is open longer than 3 minutes or 10 successive limit trips occurred during high heat. Control will auto reset after three hours. Refer to status code 33.

STATUS CODE 14 - IGNITION LOCKOUT

Control will auto reset after three hours. Refer to status code 34.

STATUS CODE 15 - BLOWER MOTOR LOCKOUT

Indicates the blower failed to reach 250 RPM or the blower failed to communicate within 30 seconds after being turned ON in two successive heating cycles. Control will auto reset after 3 hours. Refer to status code 41.

A06026

Fig. 15 - Detail of Furnace Board

577D-- -- A

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Contents Table of Contents Installation InstructionsReceiving and Installation Safety ConsiderationsIntroduction Check EquipmentRig and Place Unit Provide ClearancesUNIT/STRUCTURAL Damage Hazard Unit Falling HazardCPRFCURB010A00 SizeCPRFCURB011A00 CPRFCURB012A00577D--A24-30 Unit Dimensions 577D--A36-60 Unit Dimensions Physical Data Unit 577D--A Indoor FAN Physical Data Con’t Unit 577D--APersonal Injury Hazard Select and Install DuctworkCabinet Model Rigging Weight Supply and Return Duct Opening Provide for Condensate DisposalCarbon Monoxide Poisoning Hazard Install Flue HoodInstall Gas Piping Unit Component Damage Hazard Install Electrical ConnectionsFire or Explosion Hazard Electronic Air Cleaner Outdoor Air Temperature Sensor OATMaximum Gas Flow Capacity Humidifier ConnectionsTypical Installation Control Plate PRE-START-UP Unit Start-Up and TroubleshootingSTART-UP FIRE, EXPLOSION, Electrical Shock and Environmental HazardFurnace Control Troubleshooting Indoor Fan Motor Troubleshooting577D a A10217L A10219C A10219L HP/AC Control Troubleshooting Unit Operation Hazard Sequence of OperationHeat Pump/Air Conditioner Board Status Codes Air Delivery and Temperature Rise at Rated Heating InputEvolution Controlled LOW Ambient Cooling Dehumidification ModeCheck GAS Input Natural GAS Unit Damage HazardU.S.A Fire and Unit Damage HazardAltitude Derate Multiplier for U.S.A CanadaCheck Burner Flame Check GAS Input Propane GASCheck for Refrigerant Leaks Start-Up AdjustmentsFilter Pressure Drop Table IN. W.C Heating InputsECM Wet Coil Pressure Drop IN. W.C Cooling Charging Table-Subcooling Maintenance Electrical Controls and Wiring Inducer Pressure SwitchOutdoor Coil, Indoor Coil, and Condensate Drain Pan Outdoor FanRefrigerant Circuit Pressure Switches Refrigerant CircuitIndoor Airflow Copeland Scroll Compressor Puron RefrigerantTroubleshooting Final Checks Care and Maintenance Observe all warnings, cautions, and bold text Symptom Cause Remedy Troubleshooting Chart CoolingBurners will not ignite Troubleshooting Chart Gas Furnace OperationTemperatures START-UP ChecklistPreliminary Information Model no III. START-UP Electrical Supply Voltage Compressor Amps

577D----A specifications

The Bryant 577D----A is a highly regarded model in the HVAC industry, representing a blend of efficiency, performance, and advanced technology. This heating and cooling unit is designed to cater to a variety of residential and light commercial applications, making it a versatile choice for consumers looking to enhance their indoor climate control systems.

One of the standout features of the Bryant 577D----A is its impressive energy efficiency rating. With a Seasonal Energy Efficiency Ratio (SEER) typically exceeding 14, this model is engineered to reduce energy consumption, helping homeowners lower their utility bills while minimizing environmental impact. The unit also employs a two-stage cooling system, which not only improves comfort by maintaining more consistent temperatures but also provides enhanced dehumidification during hotter months.

The technology used in the Bryant 577D----A is noteworthy. The unit incorporates a variable-speed compressor that adapts to the specific cooling or heating needs of the space, ensuring optimal performance at all times. This advanced feature not only contributes to energy savings but also allows for quieter operation compared to single-stage systems. The inclusion of a smart thermostat integration further enhances convenience, enabling users to manage their HVAC system remotely and optimize settings according to their schedules.

Additional characteristics of the Bryant 577D----A include a durable construction designed to withstand various environmental conditions. The cabinet is made from quality materials that protect against corrosion and other factors that could affect the unit's longevity. Furthermore, the unit operates quietly, thanks to sound-dampening technologies, which is a significant advantage for residential areas where noise can be a concern.

Maintenance is also simplified with the Bryant 577D----A, as it is equipped with self-diagnostics for easy troubleshooting. This feature alerts users to potential issues before they escalate, promoting efficient operation and prolonging the lifespan of the system.

In conclusion, the Bryant 577D----A stands out as a superior choice for those seeking reliability and efficiency in their HVAC solutions. With its energy-efficient operation, advanced technologies, and robust construction, it serves as a valuable investment for homeowners committed to comfort and sustainability.
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