Clocking a 2# Gas Meter

Zman

A while back there was a discussion about adjusting the BTU content of natural gas in a 2# system.
Someone posted a formula that even allowed for a high-altitude adjustment.
I know I saved the darn thing but cannot find it.
Does anyone remember or know the formula?

ratio

Check here: https://forum.heatinghelp.com/discussion/comment/1617339#Comment_1617339

Mike_Sheppard

(Atmospheric pressure + gas pressure) / base pressure = pressure correction

Atmospheric pressure = the atmospheric pressure at your location.

Gas pressure = the gas pressure entering the meter

Base pressure = the referenced atmospheric pressure that your gas supply company uses. Most of the time this is equal to atmospheric pressure, but sometimes it is not.

For example, where I live the atmospheric pressure is 14.73. Washington gas uses a base pressure of 14.92.

So my pressure correction at 2 psi would be:
(14.73 + 2) / 14.92 = 1.12

Mike_Sheppard

Zman

@Mike_Sheppard
Thanks for the follow up.
This formula checks out with an estimate I made for a spread sheet a few years ago using an actual high and low pressure meter in series. High altitude makes a big difference in the correction factor.