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Question on whether I can put a tee in a 1/2" gas line.

Minndogs Member Posts: 2
New to the forum.
Hope someone can shed some light on my project. I am installing a new Gas, fireplace insert in my upstairs family room. I installed the insert directly underneath the upstairs fireplace several years ago using 1/2" flexible copper line.
Pulled a permit, had it inspected etc... Not an expert but I have done this before. Just don't know gas line codes.

So... I would like to tee off of the existing 1/2" soft copper gas line I ran to the downstairs fireplace instead of running off of the black pipe gas line about 40' away.
I would use flare fittings and I would use 3/8 " for the new gas line to the new insert upstairs. .
Anyone know if code allows this.

Thanks much for any advice.


    EBEBRATT-Ed Member Posts: 15,346
    Sounds like the 1/2" copper would be too small. Make a sketch of the gas piping showing the length of all gas pipe runs and the BTU load of every appliance. Then we can help.

    Or call a licensed plumber or gasfitter
  • Ironman
    Ironman Member Posts: 7,353
    Gas line sizing depends upon the length of the run, the pressure, the type of gas and the amount of btus required. If the existing lines are sized to only carry what's now connected, then you can't tap into a branch to serve an additional appliance.

    We need the info that Ed requested to give you a correct answer.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • GroundUp
    GroundUp Member Posts: 1,868
    Does your lower fireplace have a regulator at it, or how far away is the reg that feeds that line? 2# gas with a reg at each appliance will easily serve 2 fireplaces, but if you're already knocked down to <14"WC at 40+ feet away you might have an issue
  • Minndogs
    Minndogs Member Posts: 2
    Got some more info together. The lower fireplace does have a regulator.
    And - the main gas run for the natural gas company's regulator outside the house looks to be 1 1/4" black gas pipe.
    All units in the house feed off this piping in the laundry room with either 1" black pipe (furnace and water heater) or, all other appliances ( kitchen cooktop, dryer, and the lower fireplace) are all fed with 1/2" copper.

    The run that I would like to tap off and supply the new fireplace is the 1/2" copper run going to the downstair fireplace. It is aprx. 41' from the 1" gas pipe that it taps off of in the laundry room. Hope this info provides enough info to determine if I can do this.

    Thanks much for all the comments.