low gas pressure to heater

[LFrankow]

Locally we get our underground pipe made out of polyethylene pipe with factory risers fused onto the end of them, not uncommon to have a 1" riser on even a 1 1/2" line at times.
It doesn't affect the flow as Boyle's or Charle's law, I cannot remember which have proven that if pipe size gets smaller pressure will increase and the same volume of gas will flow through the pipe to the appliance. In my house I have 1" gasline run to my 80,000 BTU furnace which is reduced to 1/2" to connect to the gas valve.

 

[Yetilagoon]

Excellent. Glad it's a single run. My gas line splits between the pool heater and the BBQ/fire pit. I'm always fearful of the day when my yard will need to be excavated looking for a gas leak


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Hi Joyfulnoise,
Were getting ready to start our build and this was a question that i had. We need to run about 150' from the meter to the pool heater and spit off to a fire feature and a BBQ kitchen. I was afraid their would be a pressure drop off and not be able to heat the spa If the fire feature and or BBQ were being used simultaneously?

 

[JoyfulNoise]

Hi Joyfulnoise,
Were getting ready to start our build and this was a question that i had. We need to run about 150' from the meter to the pool heater and spit off to a fire feature and a BBQ kitchen. I was afraid their would be a pressure drop off and not be able to heat the spa If the fire feature and or BBQ were being used simultaneously?

What diameter gas pipe are they running from the meter to the pool heater? Mine was 2" diameter. I have 150' of 2" line from the meter to the heater. It is tee'd off to a 1" that runs from the main 2" to my BBQ and fire pit which is probably about 50'. I can run my pool heater and fire pit with no issues. Not sure I have ever had all three running at once. Most gas grilles are, at most, 65k BTUs (some can go higher). A gas fire pit can use a lot of gas but we always run ours with a very low flame height. I have no feel for the BTU's used by it but I imagine it's not that high. If you know the manufacturer of your fire pit or gas ring, then you can probably estimate the BTUs.

Honestly, I would highly suggest you get a competent and properly licensed gas plumber to give your layout a look. They may recommend that you use a smaller diameter line at higher pressure to deliver the gas to each point and then put regulators at each point of use to lower the pressure. This would avoid pressure fluctuations due to multiple gas loads.

 

[Yetilagoon]

I was just up in the attic and found an old gas run that the previous owners had for an old jacuzzi. It comes out the stucco from the attic pretty close to where my pool pad will go. It is te'd right before the water heater in the attic and the valve is closed obviously. I measured the pipe at 1.5" hopefully that will be enough?