Goodman Mfg VC8 instruction manual General Furnace Layout

GAS SUPPLY AND PIPING

•Install a manual shutoff valve between the gas meter and unit within six feet of the unit. If a union is installed, the union must be downstream of the manual shutoff valve, between the shutoff valve and the furnace.

•Tighten all joints securely.

•Connect the furnace to the building piping by one of the following methods:

–Rigid metallic pipe and fittings.

–Semi-rigid metallic tubing and metallic fittings.

Aluminum alloy tubing must not be used in exterior locations.

–Use listed gas appliance connectors in accordance

with their instructions. Connectors must be fully in the same room as the furnace.

–Protect connectors and semi-rigid tubing against

physical and thermal damage when installed. Ensure aluminum-alloy tubing and connectors are coated to protect against external corrosion when in contact with masonry, plaster, or insulation, or subjected to repeated wetting by liquids such as water (except rain water), detergents, or sewage.

Location of Manual Valve

(Installed Ahead of

Ground Joint Pipe Union)

When the gas piping enters through the left side of the furnace, the installer must supply the following fittings (starting from the gas valve):

•90 degree elbow.

•Straight pipe to reach the exterior of the furnace.

•A ground joint union, drip leg, and manual shutoff valve must also be supplied by the installer. In some cases, the installer may also need to supply a transition piece from 1/2 inch to another pipe size.

COUNTERFLOW INSTALLATIONS

When the gas piping enters through the left side of the furnace, the installer must supply a straight pipe and a 90 degree elbow to reach the exterior of the furnace.

A ground joint union, drip leg and manual shutoff valve must also be supplied by the installer. In most cases, the installer may also need to supply a transition piece from ½” to another pipe size. When the gas piping enters through the right side of the furnace, the installer must supply the following fittings (start- ing at the gas valve):

•Close Nipple

•90 Degree Elbow

•Straight Pipe to Reach Exterior of Furnace.

GAS PIPING CHECKS

Height Required

By Local Code

Ground Joint Pipe Union

To Be Installed Ahead of

Gas Valve

Drip Leg

Reducing Coupling 1/2” x 1/8” with 1/8” Pipe Plug to Measure Line Gas Pressure

``

Before placing unit in operation, leak test the unit and gas con- nections.

WARNING

TO AVOID THE POSSIBILITY OF EXPLOSION OR FIRE, NEVER USE A MATCH OR OPEN FLAME TO TEST FOR LEAKS.

Check for leaks using an approved chloride-free soap and wa- ter solution, an electronic combustible gas detector, or other approved testing methods.

General Furnace Layout

UPFLOW INSTALLATIONS

When the gas piping enters through the right side of the fur- nace, the installer must supply the following fittings (starting from the gas valve):

•Close nipple.

•90 degree elbows.

•Straight pipe to reach the exterior of the furnace .

A ground joint union, drip leg, and manual shutoff valve must also be supplied by the installer. In some cases, the installer may also need to supply a transition piece from 1/2" to another pipe size.

NOTE: Never exceed specified pressures for testing. Higher pressure may damage the gas valve and cause subsequent overfiring, resulting in heat exchanger failure.

Disconnect this unit and shutoff valve from the gas supply pip- ing system before pressure testing the supply piping system with pressures in excess of 1/2 psig (3.48 kPa).

This unit must be isolated from the gas supply system by clos- ing its manual shutoff valve before pressure testing of gas sup- ply piping system with test pressures equal to or less than 1/2 psig (3.48 kPa).

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