Gas Pipe Sizing Questions
Hi.... I have a couple of dumb questions regarding my gas supply to a new addition. Hopefully, someone will help me understand several questions. Thanks in advance.
Issue: We are adding an addition to a small home and need to run our gas line out to the addition which will have a furnace, water heater, and gas dryer. The furnace is 100,000 btu rated, the gas dryer is 35000 and the water heater is 35000. I calculate the supply demand load at 170.
This is California under the 2006 UPC code. The gas company says my supply pressure is 8" WC. The current meter has Â¾ inch iron pipe feed to under my foundation.
The run out to the addition is 60 feet. By my code book calculations, I need to run 1 inch iron pipe to sufficiently supply the above appliances. (3/4 inch would only service a 40 foot line)
1) Do I need to run the 1" all the way to the actual meter hookup, or can I just hook up say 1 or 2 feet down the line after my Â¾ feed from the meter enters the home. (It is a much easier hook-up.) In effect, would that 1 or 2 feet of Â¾ inch be choking down to any significant degree my supply to the 1 inch line.???
2) The UPC code states that unions may not be in a concealed space. Is concealed space the same as accesable space. My real question applies to may I have a union in my crawl space that is accesable thru my trap doors. (I know that I canÂt have it in a permently sealed space like a wall cavity etc.)
3) When using the standard UPC gas pipe sizing tables, how does the UPC tables take into consideration what my supply pressure is. Would not a supply pressure of say 8" WC supply a lot more at 60 feet than a say 4"WC. Or is there a standard supply pressure throughout Ca that the UPC tables are based on.
4) Also, as a matter of interest, would not the type of pipe (and also the bends) also effect the pipe sizing as it appears to me that friction loss over the length of the pipe run is a significant variable in determining supply pipe sizing.
Just trying to understand.