Nordyne G6RC 90+ Air Requirements For One-Pipe Installation, Installation In An Unconfined Space

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Vent or

 

 

 

Chimney

 

 

 

 

Air Duct

Air Duct

 

must be

Furnace

 

at least

 

1 sq. in.

 

 

 

per 2000

 

 

 

Btuh of

 

Air Duct

total input

 

rating.

 

 

 

 

Water Heater

 

 

 

Minimum

 

 

Total Input

Free Area

Round Duct

Rating (Btuh)

(Each Opening)

Diameter

40,000

20 sq. in.

 

5"

60,000

30 sq. in.

 

6"

80,000

40 sq. in.

 

7"

100,000

50 sq. in.

 

8"

120,000

60 sq. in.

 

9"

140,000

70 sq. in.

 

10"

160,000

80 sq. in.

 

10"

Figure 13. Equipment in a Confined Space with all Combustion Air Drawn from the Outside through Horizontal Ducts

Air Requirements For One-Pipe Installation

When air for combustion is to be taken from around the furnace, a protective screen must be installed over the combustion air intake open- ing. This screen is provided with the furnace installation instructions and functions to prevent debris from entering the combustion system. It should be installed on the combustion air intake collar or inlet PVC. If furnace location is such that this opening might be unintentionally ob- structed, a 3" PVC elbow should be installed on the collar, and the screen placed inside the inlet of the elbow. See Figure 8.

Installation In An Unconfined Space

!CAUTION:

"Tight" buildings (with weather strip- ping and caulk to reduce infiltration), may require special provisions for in- troduction of outside air to ensure satisfactory combustion and venting, even though the furnace is located in an unconfined space.

An unconfined space is an area including all rooms not separated by doors with a volume greater than 50 cubic feet per 1,000 Btuh of the combined input rates of all appliances which draw combustion air from that space. For example, a space including a water heater rated at 45,000 Btuh and a furnace rated at 75,000 Btuh requires a volume of 6,000 cubic feet [50 x (45 + 75) = 6,000] to be considered unconfined. If the space has an 8 foot ceiling, the floor area of the space must be 750 square feet (6,000 / 8 = 750). In general, a furnace installed in an unconfined space will not require outside air for combustion.

!WARNING:

Furnaces installed with combustion air drawn from a heated space which includes exhaust fans, fireplaces, or other devices that may produce a negative pressure should be consid- ered confined space installations.

Installation In A Confined Space

A confined space is one which does not meet the unconfined space volume requirements, and typically involves installation in a small room. All such installations must have specific provisions for introduction of combustion and ventilation air. Codes require that two openings be pro- vided for this - one with bottom edge within 12" of the floor and one with top edge within 12" of the ceiling. The size and other criteria for these openings must be per the following sections.

Combustion air openings must not be restricted in any manner.

Furnaces installed in a confined space which supply circulating air to areas outside of the space must draw return air from outside the space and must have return air ducts tightly sealed to the furnace.

Air From Inside

Air for combustion and ventilation may be taken from inside the building through an interior wall if the building is not "tight" and if the total volume of the furnace space and the space from which air is drawn meets the volume requirements for an unconfined space. In such cases, the two openings in the wall must each have free area of at least one square inch per 1000 Btuh of total appliance input, but not less than 100 square

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Contents What to do if YOU Smell GAS Installation InstructionsPage Table of Contents Upflow G6RC & G6RD Furnaces DimensionsDownflow G6RL Furnace High 1910 1860 1780 1700 1620 1520 1420 Furnace Airflow DataModel Input Motor Number Btuh Speed Clearances to Combustible Materials Installation Requirements Requirements and CodesSupply AIR Plenum Installation Horizontal InstallationsLocation Downflow Warning G6RL ModelsFurnace on a Concrete Slab Circulating AIR SupplyVenting and Combustion AIR Requirements Return AirFree Area Minimum40,000 100 sq. 60,000 80,000 Installation In An Unconfined Space Air Requirements For One-Pipe InstallationInstallation In a Confined Space Air From InsideVent Pipe Material Venting RequirementsVent Pipe Length and Diameter Air Directly Through An Exterior WallSolution Vent Pipe InstallationExample Pipe Routing and SupportG6RL Downflow Furnaces G6RC & G6RD Upflow FurnacesFurnaces G6RC & G6RD UpflowG6RL Downflow Furnaces G6RC & G6RD Upflow FurnacesVent Termination Clearances Location of Outdoor TerminationsHorizontal Venting Alternate Horizontal Vent InstallationVent Freezing Protection Vertical VentingConcentric Vent Termination Vertical Vent Termination Drainage of Condensate from FurnaceLeak Check GAS Supply and PipingHigh Altitude Application ConversionNatural Gas High Altitude Conversion LP/Propane Gas Sea Level and High Altitude ConversionLine Voltage Wiring Electrical WiringLow Voltage Wiring START-UP and AdjustmentsFurnace Rating Orifice Drill Size Plate Input Btu/h Nat Above Sea LevelVerifying and Adjusting Firing Rate Start-Up ProcedureElectrical Data Verifying Burner Operation Verifying and Adjusting Temperature RiseGas Flow Rate GAS Flow Rate Cubic Feet PER HourDescription of Components Verifying Operation of the Supply Air Limit SwitchFor G6RC, G6RD and G6RL Residential Furnaces G6RC, G6RD and G6RL Integrated Control Board System DiagramSystem Operation Information MaintenanceLocation of Major Components G6RL Downflow FurnaceCooling Mode Heating ModeSequence of Operation Furnace Fails to Operate Fan ModeTwinning of Two Furnaces Fuel Type INSTALLATION/PERFORMANCE Check List¢707931*¤