BTU/hr for Cubic feet per hour

Brad White_200

Steve, the actual BTU content of the gas varies day to day. Your bill will have an adjustment factor for the average BTU content over the billing period.

It can vary from 950 to 1050 BTUs per CF depending on what is added or favored beyond methane which usually constitutes about 95% of NG heat value. Sometimes pentane, butane, propane and other "anes" (Rogaine?) are added based on availability and advantageous spot market prices. Most people use 1,000 and, at least in my experience, less often 1,050 BTUH per cubic foot as a base assumption.

Clocking gas flow from the gas meter meter, for as accurate as they are, is like flying a jet and using a calendar for an airspeed indicator.

If you are counting 159 CFH and are aiming for 152 MBH, less than 5 percent difference, the burner technician can adjust within reason but it may not reflect actual heat content used, nor how well it is used. That five percent could as easily be absorbed in the heat content differential.

The entire boiler and steam distribution is a <i>system</i>; you may well need the extra CFH at whatever heat content, to make steam at a rate which works for you.