Bosch 96% AFUE Gas Furnace - BGH96 Model

Overview and Certifications

The Bosch BGH96 is a 96% AFUE condensing gas furnace designed for residential applications. It is ENERGY STAR rated and features a reliable, proven two-stage design with multi-speed ECM motors for quiet and efficient operation.

Certifications:

• AHRI Certified®
• ENERGY STAR®
• ETL Listed (Intertek 3124627)

Note: This product is not to be sold or installed in the State of California in the South Coast Air Quality Management District or San Joaquin Valley Air Basin territory.

Product Features

Standard Features

• Up to 96% AFUE heating efficiency, ENERGY STAR rated.
• 5-year parts limited warranty, 20-year heat exchanger limited warranty.
• Reliable, proven two-stage design.
• Compatibility with the Bosch Connected Control BCC100 Thermostat.
• 3-way multipoise design allows for flexibility in multiple installation types.
• Field convertible gas type for natural gas to propane gas conversion.
• Multi-speed ECM motors for quiet and efficient operation.
• Hot-surface ignition for dependable operation.
• Durable aluminized steel tubular heat exchanger and stainless-steel (AL 29-4C alloy) secondary heat exchanger.
• Pairs with Bosch IDS1.0/2.0 heat pump, reaching up to 19 SEER.
• LED fault diagnostics for quick and easy service calls.

Cabinet Features

• Low profile (33.75") cabinet fits in tight spaces.
• Convenient left or right-hand connection for gas and electric service.
• Anti-rust: Painted, galvanized, 21-gauge steel cabinet, passes a 500-hour salt spray test.
• Low noise: Fully insulated (fiberglass insulation) design minimizes indoor noise.
• 3-way multipoise design allows for flexibility in multiple installation types (Upflow: side or bottom return; Horizontal).

Warranty

All models installed in one or two-family residential dwellings come standard with a 5-year limited warranty on parts and a 20-year limited warranty on primary & secondary heat exchangers. Registration on bosch-climate.us upgrades the parts warranty to 10 years and heat exchanger warranty to lifetime. Applications other than one or two-family residential dwellings receive a 1-year parts warranty and a 10-year heat exchanger warranty.

For complete warranty details, please see: https://www.bosch-climate.us/support-center/product-warranty-library/gas-furnace-warranty.html

Key Components

Diagram showing the internal layout of the furnace with numbered components. Key components include: 1. Outlet Flue Vent, 2. Flame Sensor, 3. Chamber Limit Switch-fixed, 4. Condensate Overflow Switch, 5. Inducer, 6. Door Switch, 7. Integrated Control Module, 8. Blower, 9. Transformer, 10. Condensate Trap, 11. Junction Box, 12. Condensate Collector, 13. Low Fire Pressure Switch, 14. Two-Stage Gas Valve, 15. Hot Surface Ignitor, 16. Gas Manifold, 17. Air Inlet, 18. High Fire Pressure Switch, 19. Burner, 20. Rollout Limit Switch-resettable.

Model Nomenclature

Diagram illustrating the Bosch BGH96 model nomenclature, breaking down the model number (e.g., BGH96 M 060 B 3 A) into its components: Gas Furnace, Bosch, Two-stage/x13 ECM Muti-speed, Upflow/Horizontal, 96% AFUE, 60 kBTU/hr, 17-1/2 inch Cabinet Width, 3 Tons Nominal Cooling Capacity, Serial Number.

Model Breakdown Example:

• B: Bosch
• GH: Gas Furnace
• 96: AFUE (96%)
• M: Orientation (Upflow/Horizontal)
• 060: Capacity (60 kBTU/hr)
• B: Cabinet Width (17-1/2 inch)
• 3: Nominal Cooling Capacity (3 Tons)
• A: Serial Number designation

* Nominal 350-400 CFM per 12,000 BTU/hr

Dimensions and Connections

Diagrams showing the front, left side, right side, top, and bottom views of the furnace, indicating connection points for combustion air, gas pipe, electrical, condensate drain, and thermostat wiring. The bottom view shows the panel removed. A table provides specific dimensions (Cabinet Width, Supply-Air Width, Return-Air Width) and Shipping Weight for each furnace model.

Technical Specifications

Basic Product Information & Performance

Circulating Blower Data

Combustion System Specifications

Dip Switches

Cabinet Size & Shipping Data

* All Bosch 96% AFUE Gas Furnaces come standard with Natural Gas to LP Conversion Kits. These kits are only applicable for units installed at elevations between 0 and 2,000 feet.

For LP applications above 2000 ft elevation, the manifold and inlet gas pressure requirements remain the same as stated in this manual, the only change is to the orifices used. Refer Tables 14 & 15 in Section 9.2 of the Installation, Operation, and Maintenance Manual to determine which orifice to use based on your application.

AHRI 201/240 System Performance Data

General Operating Conditions:

• Furnace designed for minimum continuous return-air temperature of 60°F (16°C) (DBT) or intermittent operation down to 55°F (13°C) (DBT).
• Return-air temperature must not exceed 85°F (29°C) (DBT).
• Not approved for installation in mobile homes, recreational vehicles, or outdoors.
• Maximum shipment stacking: 3 units high (120").
• Inlet gas supply pressures must be maintained within specified ranges for constant and reliable operation.

Inverter Ducted Split 2.0 + Cased Coil + 96% Furnace AHRI 201/240 System Performance Data

¹ SEER: Seasonal Energy Efficiency Ratio; Certified per AHRI 210/240

² EER: Energy Efficiency Ratio; Certified per AHRI 210/240

³ HSPF: Heating Seasonal Performance Factor; Certified per AHRI 210/240

* Items in bold boxes meet the requirements for ENERGY STAR

Air Delivery

The duct system should be designed and sized according to accepted national standards such as those published by: Air Conditioning Contractors Association (ACCA), Sheet Metal and Air Conditioning Contractors National Association (SMACNA) or American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) or consult The Air Systems Design Guidelines reference tables available from your local distributor. The duct system should be sized to handle the required system design CFM at the design external static pressure. The furnace airflow rates are provided in the table below.

Tables showing Air Delivery (CFM) versus External Static Pressure (in. WC) for various furnace sizes (60B, 80B, 80C, 100C, 120D) at different speed settings (H, Mid-H, Mid, Mid-L, Low). These tables provide airflow performance without a filter. An additional 0.1 in. WC static pressure should be assumed if a 3/4 inch washable media filter is used.

Air Delivery - CFM (Without Filter)

* A filter is required for each return air inlet. This table shows the airflow performance without a filter. To determine airflow performance with a filter, if a 3/4 inch (19 mm) washable media filter is used, assume an additional 0.1 in. WC available external static pressure.

** The manufacturer default fan settings are based on model

-- Indicates unstable operating conditions.

Filters

Bosch does not supply filters or filter racks with furnace units. All filters must be field supplied according to the Manufacturer recommended high velocity filter sizes and specifications shown below.

High Altitude Derating

In high altitude applications, a standard derate for altitude from National Fuel Gas Code ANSI Z223.1 of 4% per 1000 feet above sea level must be taken. Refer to the most recent version of ANSI Z223.1 for correct gas orifice based on your specific application. The furnace derate is 4% for each 1,000 feet above sea level. For Canada applications, regulation requires 10% derating between 2000-4500 ft. When an appliance is installed at elevations above 4500 ft, the certified high altitude input rating shall be reduced at the rate of 4% for each additional 1000 ft.

The table below is based upon a heating value of approximately 1,000 Btu/ft³. In some areas the gas supplier may artificially derate the gas in an effort to compensate for the effects of altitude. If the gas is artificially derated, the appropriate orifice size must be determined based upon the BTU/ft³ content of the derated gas and the altitude. Refer to the latest version of NFPA54/ANSI Z223.1 and information provided by the gas supplier to determine the proper orifice size.

High Altitude Derate Orifice Size Chart (Natural and LP Gas*)

* LP orifice based on 10 in. WC manifold pressure

** NG denotes natural gas

? The input to the furnace must be checked AFTER reorificing.

? For Canada applications, regulation requires 10% derating between 2000-4500 ft. When an appliance is installed at elevations above 4500 ft, the certified high altitude input rating shall be reduced at the rate of 4% for each additional 1000 ft.

? Units installed with natural gas at altitudes up to 2000 ft. above sea level may be installed without any modifications. Units installed above 2000 ft. of elevation must use orifices as specified in the above table.

Venting

This Category IV, dual certified (AHRI and ETL) direct vent furnace is designed for residential applications. It may be installed without modification to the condensate system in a basement, garage, equipment room, alcove, attic or any other indoor location where all required clearance to combustibles and other restrictions are met*. The combustion air and the venting system must be installed in accordance with Section 5.3, Air for Combustion and Ventilation, of the National Fuel Gas Code Z223.1/NFPA 54 (latest edition), or Sections 7.2, 7.3 or 7.4 of CSA B149.1, National Gas and Propane Codes (latest edition) or applicable provisions of the local building code and these instructions.

This furnace requires a special venting system. This furnace is for use with schedule-40 PVC, PVC-DWV, CPVC, or ABS-DWV pipe, and must not be vented in common with other gas-fired appliances. Construction through which vent/air intake pipes may be installed is maximum 24 inches (610 mm), minimum 3/4 inches (19mm) thickness (including roofing materials). Refer to Section 8 "Vent System" of the Installation, Operation, and Maintenance Manual, for installation instructions related to venting.

* The condensate from this unit is acidic; adhere to all local and national codes when draining condensate. If proper procedures are not followed, this may lead to property damage.

Diagrams illustrating three common venting and combustion air intake configurations: 1. Gable Vent with Soffit Vent and Ventilated Attic, 2. Gable Vent with Soffit Vent and Ventilated Crawl Space, 3. Gable Vent with Soffit Vent and Ventilated Attic (alternative setup).

Equivalent Pipe Length

The equivalent length of the vent system is the total length of straight pipe PLUS the equivalent length of all of the elbows.

Maximum Equivalent Pipe Length

Rules for Pipe Length:

• Long radius (sweep) elbows are recommended. Standard elbows reduce total allowable pipe length. Short radius elbows are not allowed.
• Maximum equivalent length applies separately to vent piping and air intake piping.
• Three vent terminal elbows (two for vent, one for combustion air intake) are accounted for and need not be included in calculations.
• All pipes and fittings must conform to ANSI and ASTM standards (e.g., Schedule 40 PVC, CPVC, ABS-DWV). Use appropriate cement and primer. Metallic materials are not permitted for venting or air intake.
• Flexible connectors must be acid-resistant and rated for at least 225°F.
• Models have 2" vent connections. For 3" pipe, transition must be as close to the furnace as possible.
• Canadian vents must be certified to ULC S636.
• First three feet (900 mm) of vent in Canada must be accessible for inspection.
• Minimum vent length for all models is 5 feet.

Example Calculation: An 80,000 BTUH furnace requires 32 ft of pipe and four 90° elbows. Using 2" pipe and standard elbows results in 72 equivalent feet, exceeding the 60 ft limit. Using 2" pipe and sweep elbows results in 52 equivalent feet, which is acceptable. Using 3" pipe and standard elbows results in 72 equivalent feet, which is acceptable.

Required Clearance to Combustibles

Diagram showing the required clearances from combustible construction for the furnace. Clearances are indicated for the Front (3 inches), Top/Plenum (1 inch), Back (0 inches), and Sides (0 inches). An asterisk (*) indicates specific considerations for horizontal installation and service access.

* When the unit is installed in the horizontal orientation, there must be 7" clearance for the externally mounted drain trap.

Ø 24 inches is required for service and maintenance.

Horizontal installation in attic or crawl space: Indicates supply or return sides when furnace is in the horizontal position. Line contact is permissible between lines formed by intersections of the side and back of the furnace cabinet and building joists, studs, or frame. Horizontal applications require a solid, supportive structure for installation.

Unit Wiring Diagram

Schematic wiring diagram illustrating the connections for heating and cooling applications with a 2-stage thermostat. It shows connections from the thermostat to the furnace's integrated control module, including terminals for blower, gas valve, pressure switches, limit switches, ignitor, and optional components like electronic air cleaners and humidifiers. It also details power supply connections and diagnostic LED indicators.

WARNING: High Voltage: Disconnect all power before servicing or installing this unit. Multiple power sources may be present. Failure to do so may cause property damage, personal injury, or death.

Diagnostic LED Codes:

Electrical & Controls

Ratings & Physical / Electrical Data

Annual Fuel Utilization Efficiency (AFUE) numbers are determined in accordance with DOE Test procedures.

National Electrical Code (NFPA-70-latest edition) and all local codes apply.

The furnace shall be installed so that the electrical components are protected from water.

Sequence of Operations - Heating Mode

1. A call for first stage heat closes W1 contacts. Inducer blower energizes at high speed.
2. Control waits for low pressure switch contacts to close. Optional humidifier energizes.
3. Once low pressure switch contacts close, a 15-second pre-purge initiates.
4. Inducer changes to low speed; 120V ignitor powers on.
5. After ignitor warm-up, first stage manifold gas valve energizes (low fire). Flame must be detected within 4 seconds.
6. If flame is detected, a 45-second HEAT delay-to-fan-on period begins.
7. After delay, circulator fan energizes at low heat speed. Optional electronic air cleaner energizes.
8. For a two-stage thermostat, a call for second stage heat (W1 & W2) energizes inducer at high speed and circulator at high heat speed. Second stage pressure switch contacts close, energizing the second stage gas valve (high fire).
9. For a single-stage thermostat, a call for heat (W1) activates a heat staging timer (10, 20 min, or auto). After delay, second stage heat energizes as above.
10. When second stage is satisfied, inducer motor reduces to low speed, second stage gas valve de-energizes. Circulator remains at high heat speed for 30 seconds, then reduces to low speed.
11. When first stage is satisfied, first stage gas valve de-energizes, initiating HEAT delay-to-fan-off.
12. Inducer postpurges for 15 seconds, then inducer and humidifier turn off.
13. Upon completion of HEAT delay-to-fan-off, circulator turns off. Electronic air cleaner de-energizes.

Ignition Failure & Retries: If flame is not detected during trial-for-ignition or is lost before 10 seconds of establishment, the gas valve de-energizes, ignitor turns off, and the control enters a "retry" sequence (60-second wait with inducer interpurge). Two retries are allowed before system lockout. Flame established for >10 seconds clears the retry counter. Loss of flame after 10 seconds restarts the ignition sequence. Momentary loss of gas supply, flame blowout, or shorted/open flame probe circuit is sensed within 2 seconds; gas valve de-energizes, ignitor turns off, ignition sequence restarts. Recycles occur if gas supply returns or fault is corrected before the last attempt; otherwise, system lockout occurs. Lockout can be reset by momentary power interruption (10 seconds or longer).

Timing Specifications & Optional Switch Positions

(All times are in seconds, unless noted otherwise)

* These times will vary depending on option switch position.

When using a single stage thermostat, second stage delay is based on the setting of switch S1-1 & S1-2 dip switches.

Optional Switch Positions - Heat Off Delay

Optional Switch Positions - Cool Off Delay