Shut off the gas at the meter, (Obvious) remove all piping necessary back to area desired. Use the yellow Teflon tape, because it is approved and has consistent thickness, or use Teflon pipe dope. Use a black pipe CAP do not use a plug in a fitting.(some jurisdictions do not allow the use of pipe plugs on gas piping due to the plug possibly cracking the fitting if tightened to tight.)
Turn the gas back on and use a 50%mixture of dish washing soap and water and spray all piping connections that have been disturbed. If no bubbles show up, go to the meter and turn on the gas and observe the lowest meter needle for movement for five minutes, if you have no movement of the meter then the piping system is sound and you can relight the pilots on the water heater or any other appliances.
another concern on the fireplace is that the damper is normally removed or pinned open when a gas insert is installed, you may want to have it reinserted or made so that it can be closed when you are not burning your fireplace. An open fireplace will double the infiltration of outside air to the house
The question of using normal or yellow Teflon tape has to do with the thickness of the tape. The yellow tape is thicker and meets specifications set by the AGA for gas piping.
Functionally you could use the white tape if you used enough wraps to get the thickness of the yellow tape but it is not approved for use on gas piping and could possibly cause a question in case of a fire on you insurance.
Last edited by master53yoda; 02-11-2009 at 04:07 PM.
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