Bryant 120 instruction manual Blocked vent shutoff switch used in Chimney Adapter Kit

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312A

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11NO PREVIOUS CODE – Stored codes are erased after 72 hours. On RED LED boards stored status codes can also be erased whenever power (115V or 24V) is interrupted. Run system through a low-heat, high-heat, or cooling cycle to check system.

12BLOWER ON AFTER POWER UP – (115V OR 24V) – Normal operation. Blower runs for the selected blower off- delay, if unit is powered up during a call for heat (R-W/W1 closed) or when (R- W/W1 opens) during the blower on-delay period.

13LIMIT CIRCUIT LOCKOUT – Lockout occurs if the limit, draft safeguard, flame rollout, or blocked vent switch* (if used) is open longer than 3 minutes. Control will auto-reset after 3 hours. See code 33.

14IGNITION LOCKOUT – System failed to ignite gas and prove flame in 4 attempts. Control will auto-reset after 3 hours. See status code 34.

21GAS HEATING LOCKOUT – Turn off power and wait 5 minutes to retry. Check for:

-Stuck closed gas valve relay on control.

-Miswire or short to gas valve wire.

22ABNORMAL FLAME-PROVING SIGNAL Flame is proved while gas valve is de- energized. Inducer will run until fault is cleared. Check for:

-Stuck open or leaky gas valve.

23PRESSURE SWITCH DID NOT OPEN Check for:

-Obstructed pressure tube.

-Pressure switch stuck closed.

24SECONDARY VOLTAGE FUSE IS OPEN Check for:

-Short circuit in secondary voltage (24V) wiring including thermostat leads. Disconnect thermostat leads to isolate short circuit.

31 HIGH-HEAT PRESSURE SWITCH OR

RELAY DID NOT CLOSE OR

REOPENED - Check for:

- Control relay may be defective.

32LOW-HEAT PRESSURE SWITCH DID NOT CLOSE OR REOPENED – If open longer than 5 minutes, inducer shuts off for 15 minutes before retry. If opens during blower on-delay period, blower will come on for the selected blower off- delay. Check for:

-Proper vent sizing.

-Low inducer voltage (115V).

-Low inlet gas pressure (if LGPS used).

-Inadequate combustion air supply.

-Disconnected or obstructed pressure tubing.

-Defective inducer motor.

-Defective pressure switch.

-Excessive wind.

-Restricted vent.

33LIMIT CIRCUIT FAULT – Indicates the limit, draft safeguard, flame rollout, or blocked vent shutoff switch* (if used) is open.Blower will run for 4 minutes or until open switch remakes whichever is longer. If open longer than 3 minutes, code changes to lockout #13. If open less than 3 min. status code #33 continues to flash until blower shuts off. Flame rollout switch and BVSS requires manual reset. Check for:

-Dirty filter or restricted duct system.

-Loose blower wheel.

-Defective switch or connections.

-Defective blower motor or capacitor.

-Inadequate combustion air supply (flame rollout switch open).

-Restricted vent.

-Proper vent sizing.

-Excessive wind.

34IGNITION PROVING FAILURE – If flame is not sensed during the trial for ignition period, the control will repeat the ignition sequence 3 more times before lockout #14 occurs. If flame signal is lost during the blower on-delay period, blower will come on for the selected blower off-delay. Check the following items first before proceeding to the next step.

-Gas valve turned off.

-Manual shut-off valve.

-Green/Yellow wire MUST be connected to furnace sheet metal.

-Flame sensor must not be grounded. To determine whether the problem is in the gas valve, igniter, or flame sensor the system can be operated in the component test mode to check the igniter. First remove the R thermostat connection from the control and initiate the component test sequence. Does the igniter glow orange/white by the end of the 15 second warm-up period?

NO

YES

43LOW-HEAT PRESSURE SWITCH OPEN WHILE HIGH-HEAT PRESSURE SWITCH IS CLOSED - Check for:

-Low-heat pressure switch stuck open.

-Disconnected or obstructed pressure tube.

-Miswired pressure switches.

-Low inlet gas pressure (if LGPS used).

Unplug igniter harness from control and initiate another component test sequence. Check for 115V between pin 1 and NEUTRAL-L2 on the control. Was 115V present for the 15 second period?

Reconnect the R thermostat lead and set thermostat to call for heat. Connect voltmeter across gas valve connections. Does gas valve receive 24V?

YES

Does gas valve open and allow gas to flow?

YES

Do the main burners ignite?

YES

Do the main burners stay on?

NO

Repeat call for heat and check flame sensor current during trial for ignition period. Is the DC microamps below 0.5?

YES

Clean flame sensor with fine steel wool and recheck current. Nominal current is 4.0 to 6.0 microamps.

Is current near typical value?

YES

Will main burners ignite and stay on?

YES

Fixed.

45 CONTROL CIRCUITRY LOCKOUT Auto-

 

 

 

reset after 1 hour lockout due to:

 

 

 

- Flame circuit failure.

 

 

 

- Gas valve relay stuck open.

 

 

 

- Software check error.

 

 

 

Reset power to clear lockout. Replace

 

 

 

control if code repeats.

NO

 

Replace furnace control.

 

 

 

YES

 

Check for continuity in the harness and igniter.

 

 

 

Replace defective component.

NO

 

Check connections. If OK, replace control.

 

 

 

 

 

 

Check that all gas valves are turned on.

 

 

 

Replace valve.

 

 

 

Check for:

 

 

 

- Inadequate flame carryover or rough

NO

 

ignition.

 

 

 

- Low inlet gas pressure.

NO

 

- Proper firing rate.

 

- Blocked or incorrect carry- over gap.

 

 

 

YES

 

(.045” nominal)

 

Allow blower to come on and repeat test to

 

 

 

 

 

 

check for intermittent operation.

NO

 

Check connections and retry. If current is

 

near typical value (4.0-6.0 nominal) and

 

 

 

 

 

 

burners will not stay on, repeat check in high-

 

 

 

heat. If burners will still not stay on replace

 

 

 

control. If burners operate in high-heat then

 

 

 

switch to low-heat, check manifold pressure.

 

 

 

If OK, check burner carryover and flame

 

 

 

sensor location.

NO

 

Replace electrode.

 

 

 

NO

 

Replace furnace control.

 

 

 

-

Gas valve is miswired.

-

See status code 32.

* Blocked vent shutoff switch used in Chimney Adapter Kit

A05001

Fig. 63 - Troubleshooting Guide 2-Speed

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Page 55 Page 57
Contents Ama CUT Hazard Safety ConsiderationsFurnace Reliability Hazard Dimensions IntroductionWidth Bottom Flue Cabinet SizeInstallation Electrostatic Discharge ESD Precautions Procedure Codes and StandardsCarbon Monoxide Poisoning and Unit Damage Hazard LocationGeneral FIRE, Injury or Death Hazard Fire HazardProperty Damage Hazard Location Relative to Cooling EquipmentAIR for Combustion Ventilation Furnace Corrosion HazardCarbon Monoxide Poisoning Hazard Outdoor Combustion Air MethodAir for Combustion, Ventilation and Dilution for Outdoors Installation Upflow InstallationDownflow Installation Horizontal InstallationFIRE, EXPLOSION, and Carbon Monoxide Poisoning Hazard Suspended Furnace SupportFloor and Plenum Opening Dimensions Roll-Out ProtectionWidth Opening dimensionsFurnace Plenum Opening Floor Opening Casing Horizontal Unit Suspension Filter Arrangement Carbon Monoxide Poisoning Hazard AIR DuctsGeneral Requirements Ductwork Acoustical Treatment Supply Air ConnectionsAir Delivery CFM With Filter Speed External Static Pressure IN. WC Size Inlet2380 2285 2200 2085 1970 1835 Air Delivery CFM With Filter* Downflow FurnacesReturn Air Connections GAS Piping Fire or Explosion HazardUpflow Return Air Configurations and Restrictions Maximum Capacity of Pipe Furnace Damage HazardWiring Electrical Connections Electrical Shock and Fire HazardElectrical Shock Hazard Furnace MAY not Operate HazardElectrical Connection to J-BOX Electrical DataBOX Relocation Power Cord Installation in Furnace J-BOX BX. Cable Installation in Furnace J-BOXElectrical Box on Furnace Casing Side. See Fig Fire or Electrical Shock HazardTwo-Stage Furnace with Two-Speed Air Conditioner See notes 2, 11, and 12 on the page following these figures Accessories VentingGeneral Venting Requirements Masonry Chimney RequirementsChimney Inspection Chart Appliance Application Requirements Vent Height Internal Area of ChimneyUpflow Application-Vent Elbow Up Downflow Application-Vent Elbow Up Horizontal Right Application Vent Elbow Right Furnace Vent Orienta Orientation Tion PUTBTUH/HR Diameter Height FTRounded End of Knockout Burn HazardSTART-UP, ADJUSTMENT, and Safety Check Start-Up ProceduresGeneral Fire and Explosion HazardAdjustments Stage Furnace Setup Switch DescriptionU.S Altitude Derate Multiplier for U.S.ARedundant Automatic Gas Control Valve Seconds Size of Test Dial For Revolution Gas Rate cu ft/hrFurnace Overheating Hazard Speed Selection Color Speed AS ShippedDesired Heating Mode Setup Switch Blower OFF Delay SEC Check Safety ControlsStage Furnace Blower OFF delay Setup Switch Checklist Altitude Range Specific Gravity of Natural GASBTUH/CU Gravity6001 to Specific Gravity of Natural GAS Altitude Range Heat Value Specific Gravity of Natural GAS Altitude RangeBTUH/CU FT Service and Maintenance Procedures Electrical SHOCK, Fire or Explosion HazardFIRE, Personal Injury and Unit Damage Specific Gravity of Natural GAS Heat Value AT AltitudeCare and Maintenance Electrical Controls and Wiring Electrical Shock HazardIntroduction Unit Operation HazardService Wiring Diagram Cleaning AND/OR Replacing AIR Filter Filter size informationBlower Motor and Wheel Electrical Shock Hazard Furnace Filter Size CasingCleaning Heat Exchanger Unit Damage HazardSequence of Operation Igniter Position Top ViewTwo-Stage Heating Adaptive mode with Single-Stage Thermostat Single-Speed Cooling Single-Stage Thermostat and Two-Speed Cooling Adaptive ModeThermidistat Mode Continuous Blower Mode Wiring DiagramsTroubleshooting Troubleshooting Guide 2-Speed Blocked vent shutoff switch used in Chimney Adapter Kit Page Catalog No. II312A---45---8

120 specifications

The Bryant 120 is a remarkable system designed for residential and commercial heating and cooling needs, showcasing an impressive blend of efficiency, reliability, and advanced technology. As a part of Bryant's extensive line of HVAC solutions, the Bryant 120 stands out with its features and performance, making it an ideal choice for those seeking comfort year-round.

One of the main features of the Bryant 120 is its exceptional energy efficiency. It boasts a high Seasonal Energy Efficiency Ratio (SEER) rating, enabling homeowners to save on energy costs while enjoying consistent temperature control. This efficiency is aided by its variable-speed compressor, which allows the system to adjust its output based on current requirements, optimizing both energy consumption and comfort.

In terms of technology, the Bryant 120 incorporates advanced controls that enhance user experience and system performance. The system comes equipped with smart thermostats that allow homeowners to monitor and adjust their environment remotely. These thermostats not only provide convenience but also help in optimizing energy usage by learning the household's heating and cooling patterns.

Another characteristic of the Bryant 120 is its durable construction. The unit is built to withstand various weather conditions, featuring a robust cabinet and components designed for longevity. This durability ensures that homeowners can rely on the system for years without the need for frequent repairs or replacements.

Noise levels are also a critical consideration in HVAC systems, and the Bryant 120 addresses this with its quiet operation. The system is designed to minimize sound output, making it suitable for residential areas where noise can be a concern. This is particularly beneficial for nighttime use, providing a comfortable sleeping environment.

Additionally, the Bryant 120 supports eco-friendly refrigerants that comply with environmental standards, contributing to a reduction in greenhouse gas emissions. This commitment to sustainability reflects Bryant's dedication to creating products that are not only effective but also responsible.

Overall, the Bryant 120 encapsulates a harmonious balance of efficiency, advanced technology, durability, and quiet operation. Whether for a new installation or a replacement, the Bryant 120 presents an ideal solution to meet diverse heating and cooling requirements, enhancing comfort while prioritizing energy savings and environmental responsibility.
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