Calculating gas load

[nbpt100]

I am considering adding another gas appliance. How do I calculate if the current line coming into the house can handle the potential extra demand? I was told there are charts that are based on the main line pipe diameter. It will give you the BTU/Hr total for the house. What is this chart called and where can I find it? Thanks.

 

[Dagny]

Rego regulators has a little service mans booklet with what you need I carry one in my truck. Must be on the net somewhere.

 

[PoorUB]

I am considering adding another gas appliance. How do I calculate if the current line coming into the house can handle the potential extra demand? I was told there are charts that are based on the main line pipe diameter. It will give you the BTU/Hr total for the house. What is this chart called and where can I find it? Thanks.

Natural gas or propane? With natural gas the limiting factor is generally the gas meter. It should have a tag with the model number which usually refers to the BTU size of the meter, for example a X-250 is 250,000 BTU.

Also, you need to know the gas pressure entering the house, natural gas is usually 1/2 PSI or 2 PSI. Propane is often 1/2 PSI, but can be run 10 PSI from the tank and regulated down to 1/2 PSI of 2 PSI at the house.

Either way there are charts on the internet.

 

[Firebrick43]

Rego regulators has a little service mans booklet with what you need I carry one in my truck. Must be on the net somewhere.

https://www.regoproducts.com/content/dam/pes/pdfs/L-545_Servicemans_Manual.pdf

 

[mm08822]

Make a simple sketch of the loads connected to the meter.
Include gas pipe diameters and lengths. Show each load and BTUH demand.

From this info, you can check the best way to connect the new load from either existing piping or new/modified piping. Helps to understand worst case pressure drops.

This also tells you what the worst case demand could be. There is usually a diversity factor applied that adjusts the total connected load to a likely simultaneous load.......e.g. - you could run you furnace, stove and dryer at the same time, but unlikely to run all of that and your hwh, gas fireplace and outgrill.

 

[nbpt100]

Natural gas or propane? With natural gas the limiting factor is generally the gas meter. It should have a tag with the model number which usually refers to the BTU size of the meter, for example a X-250 is 250,000 BTU.

Also, you need to know the gas pressure entering the house, natural gas is usually 1/2 PSI or 2 PSI. Propane is often 1/2 PSI, but can be run 10 PSI from the tank and regulated down to 1/2 PSI of 2 PSI at the house.

Either way there are charts on the internet.

Natural gas. Model is I-250. Can I assume it is 250,000 Btu/hr?

 

[mm08822]

Natural gas. Model is I-250. Can I assume it is 250,000 Btu/hr?

Yes, but also pull the specs off of the regulator as a doublecheck to what its throughput is. (Usually not an issue)

 

[nbpt100]

Make a simple sketch of the loads connected to the meter.
Include gas pipe diameters and lengths. Show each load and BTUH demand.

From this info, you can check the best way to connect the new load from either existing piping or new/modified piping. Helps to understand worst case pressure drops.

This also tells you what the worst case demand could be. There is usually a diversity factor applied that adjusts the total connected load to a likely simultaneous load.......e.g. - you could run you furnace, stove and dryer at the same time, but unlikely to run all of that and your hwh, gas fireplace and outgrill.

I get it. Very, very, very unlikely I will run all 4 stove burners and the oven at the same time. Currently I have a HWH, furnace, stove and one gas fireplace. Looking to add a 2nd gas fireplace.

 

[HoosierBuddy]

American Meter rates an I-250 at 250,000 BTU at 0.5" Water Column differential and 400,000 BTU/Hour at 1" W/C differential.

There are sizing charts like the one below online, but when I actually run flow numbers on GasCalc, these charts look way-way conservative.

 

[fitter30]

Need input gas btu's of all gas appliances, size and lengths of the pipe. Adding 250k btu's? Any external regulators before water heater or, furnace. Drawing would help. Call your gas company they can tell you btu capacity for your meter and house pressure.

 

[PoorUB]

Another thing to consider, what is the chances of all the appliances running at one time? I would bet you won't run both fire places at once, unless the furnace quits. Or run al the burners on the range.

40 gallon gas water heater, or a 200,000 BTU tankless?

Gas fireplace? What, 40,000 BTU more? Personally, I wouldn't worry about it,