Installation - direct gas piping, Step 3 connect the supply gas line, Step 2 install additional regulator if required – Greenheck DG / DGX with Direct Spark (464043 IOM) (Pre-2008) User Manual
Page 11: Step 4 test the system for leaks, Warning

11
Installation - Direct Gas Piping
Installation
To
Controls
Gas Cock
From
Gas
Supply
6 in. Trap
1/8 in. Plugged Tap
Ground Joint Union
Step 3 Connect the Supply Gas Line
A manual shut off valve (gas cock), 1/8 in. plugged
test port and 6 in. drip leg must be installed prior to
the gas train. The valve and the test port must be
accessible for the connection of a test gauge. Supply
gas connections must be made by a qualified installer
and are not furnished by Greenheck.
Step 2 Install Additional Regulator if
Required
When the supply gas pressure exceeds the maximum
gas pressure shown on the direct gas nameplate, an
additional regulator (by others) is required to reduce
the pressure. The regulator must have a listed leak
limiting device or it must be vented to the outdoors.
Step 4 Test the System for Leaks
Check both the supply lines and the factory piping for
leaks. Apply a soap and water solution to all piping
and watch for bubbling which indicates a leak.
WARNING!
The factory piping has been checked for leaks,
but should be rechecked due to shipping and installation.
WARNING!
NEVER test for a gas leak with an open flame.
NOTE!
The regulator located inside the unit is used to
adjust the unit’s maximum output temperature.
Supply Gas Line