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Larger gas line AFTER meter?

MarkSpline Member Posts: 2
edited April 2022 in Gas Heating
We want to put in a 300,000btu pool heater. Pool is about 100' feet from the gas meter. Instructions for the pool heater state I need a 1-1/4" gas line for this distance.

I have called the utility company and they assessed our meter, current and anticipated needs and determined we need a meter upgrade. I assumed as much, the pool heater is bigger then the capacity of our current meter alone. The gas line coming to the house is 1". The utility company stated that the gas line exiting the new meter is 1". I know the incoming line is higher pressure and it doesn't need to be upgraded to a larger line. However my concern is the 1" output. I informed the engineer that was assigned to my project of such. He informed me that there is no issue: I can put on a 1" nipple, bushing the pipe to 1-1/4", put on my 1-1/4" tee for the pool heater line, and then bushing back down to 1". He claims my flow will not be compromised.

That, does not make sense in my head, but I don't deal with gas lines.....is that true?


  • heathead
    heathead Member Posts: 234
    edited April 2022
    The simple answer is it is a very short section of 1 inch pipe. The loss through that section is low because it is not very long.
  • Jamie Hall
    Jamie Hall Member Posts: 23,433
    They're looking at pressure drop and variability The larger line is needed to reduce the pressure drop along its length, but as @heathead said, a short section of 1 inch line isn't going to make any difference at all.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • MarkSpline
    MarkSpline Member Posts: 2
    I appreciate the consensus, thank you very much!
    EBEBRATT-Ed Member Posts: 15,616

    You should be fine but, in most areas, bushings are not allowed on gas piping. Use reducing elbows, reducing tees or reducing couplings to configure the piping. Keep the 1 1/4 pool heater connection as reasonably close to the meter as possible

    You should come off the meter with a coupling or elbow to immediately increase the line size to meet whatever size pipe you need for your total load (1 1/2")? and then say a 1 1/2 x 1 1/2 x 1 1/4 tee to feed the pool heater and the other end of this tee would feed your existing house load.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    My whole house gen Rees and goes from 3/4” to 1 1/4”, then back to 3/4” at the gen. It’s fine as other have stated.

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