pipe sizing for seismic gas valve
I'm stumped on the sizing I need for a seismic gas shutoff valve for my home. The pipe from the utility is 3/4 inch before and after the gas meter. It then immediately branches off to two 1" pipes that serve a hot water heater, gas dryer, furnace and pool heater. I'm thinking if the pipe coming out of the meter is 3/4" a similarly sized valve should be fine. But a supplier wants to sell me a 1.5" valve, which would be a LOT of trouble to install. Can a gas plumber give me some advice? Thanks.