Gas Piping Checks - Bosch BGH96M060B3B Installation Instructions Manual

Installation Instructions
The following stipulations apply when connecting gas piping.
Use pipe joint compound on male threads only. Pipe joint compound
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must be resistant to the action of the fuel used.
Use ground joint unions.
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Install a drip leg to trap dirt and moisture before it can enter the gas
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valve. The drip leg must be a minimum of three inches long.
Install a 1/8" NPT pipe plug fitting, accessible for test gage connection，
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immediately upstream of the gas supply connection to the furnace.
Use two pipe wrenches when making connection to the gas valve to
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keep it from turning. The orientation of the gas valve on the manifold
must be maintained as shipped from the factory.
Install a manual shutoff valve between the gas meter and unit within six
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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.
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Connect the furnace to the building piping by one of the following
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methods:
1. Rigid metallic pipe and fittings.
2. Semi-rigid metallic tubing and metallic fittings. Aluminum alloy
tubing must not be used in exterior locations.
3. Use listed gas appliance connectors in accordance with their
instructions. Connectors must be fully in the same room as the
furnace.
4. The installation of piping shall be in accordance with piping
codes and the regulations of the local gas company. Pipe joint
compound must be resistant to the chemical reaction with
liquefied petroleum gases.
When the gas piping enters through the right side of the furnace， the installer must
supply the following fittings (starting from the gas valve):
90 degree elbows (2).
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Close nipple.
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Straight pipe to reach the exterior of the furnace.
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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.
When the gas piping enters through the left side of the furnace, the installer must
supply the following fittings (starting from the gas valve):
Straight pipe to reach the exterior of the furnace.
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A ground joint union, drip leg, and manual shutoff valve must also be
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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.
3 8 |
Location of Manual value
(Installed Ahead of Ground
Joint Pipe Union)
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
Figure 34 Typical Gas Pipe Arrangement

9.5 Gas Piping Checks

Before placing unit in operation, leak test the unit and gas connections.
WARNING: FIRE OR EXPLOSION HAZARD
Never test for gas leaks with an open flame. Use a
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commercially available soap solution made specifically for
the detection of leaks to check all connections.
Check for leaks using an approved chloride-free soap and water solution,，an
electronic combustible gas detector，or other approved testing methods.
NOTICE:
Never exceed specified pressures for testing. Higher
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pressures may damage the gas valve and cause
subsequent overfiring， resulting in heat exchanger failure.
This furnace must be isolated from the gas supply system by closing its manual
shutoff valve before pressure testing of gas supply piping system with test
pressures equal to or less than 1/2 psig (3.48 kPa).
Bosch 96% AFUE Condensing Gas Furnace - BTC 770503101 J (06.2023)